BixbyFAQ
From Cornburning
Got a Problem?
This page presents technical guidance for running and troubleshooting your Bixby stove. If you can't find your answer here or in the Bixby Main Page, consider posting your question on the iburncorn forumor contacting Bixby. The more completely you present your problem and the circumstances leading to it, the better you can be helped. In that regard, the following is a general checklist that you might wish to refer to for expressing your problem.
- What is the stove model & age?
- When and how was the stove last cleaned?
- Describe setup and venting and termination cap.
- When and how was the venting last cleaned?
- Describe trim pot settings and any special settings in Bixcheck.
- What is the version of the stove firmware, if known?
- Describe fuel and its moisture content and cleanliness.
- What is the stove doing incorrectly?
- At what heat level setting does the problem occur?
- What has changed since it last worked correctly?
- Is it intermittent or constant?
- What error codes do you see? When?
- If intermittent, what did you observe immediately before the problem?
- What is the level of fuel in the burnpot immediately before the problem and, say, during the 30 minutes leading to the problem?
- What have you tested or done so far to investigate or rectify the problem?
- Describe colour/thickness/shape/hardness of clinkers.
- Is the stove connected to an external thermostat?
If you can also provide a Bixcheck data log that captures the problem event, that would be ideal.
Bixby Adjustment (Trim Pot) Knobs (from iburncorn forum) 
The Basics
- To adjust the trim pots, Kdyrt49 thinks of them as the carburator adjustments of an automobile and the buttons on the panel as the throttle.
If the stove cannot seem to get a nice flame, and the burn pot fills up, then it is probably not getting enough air. Check to make sure that the air trim control is not set all the way down or something. This problem is more complex and deserves closer attention than the problem of filling up simply because too much fuel is being loaded in. This problem can slowly get worse as the stove is used, which means that the only sure way to fix it is to thorougly check and clean the stove. Remedy: Turn up the air trim pot. Inspect and clean the stove
Too Much Fuel
If the fuel in the pot is building up (getting higher in the pot than it should be), then the most probable cause is that there is either not enough air or there is too much fuel in the Burn Pot. The fuel level should be about the same height as the lower burn pot, during the first few hours of operation. Too much fuel will cause excess soot on the door glass and in the exhaust. If this is happening on all levels, then the feed rate Trim Pot should be turned down. Each notch is 6% of correction. The Trim Pot should be turned one notch at a time and run for a full dump cycle before the affects will be seen.
Not Enough Fuel
Another thing that can cause a build up of fuel in the Burn Pot is that there is not enough fuel. Unfortunately too much fuel and not enough fuel end with the same result, too much fuel in the Burn Pot. If there is not enough fuel, the fuel in the pot will burn too quickly, leaving only a small amount of burning fuel and a small flame. The fuel will still be dumping in at the same rate and not all of the fuel will be lit on fire. Eventually the corn that is not on fire, will catch on fire. The excess corn will create a larger than normal flame. The excess corn will be burnt up over time, since the stove is running in a lean condition. This scenario of not having enough fuel, will usually oscillate between a flame larger than it should be on that level and then back down to a small flame, before it gets bad enough to build up in the pot. This oscillation usually takes five to ten minutes per cycle. So if the flame gets very large, then very small, this is probably a case of not enough fuel. As corn is delivered to the Burn Pot, the flame will drop slightly in size and rise back up again, this is normal. Do not confuse this with the condition of not enough fuel.
Too Much Fuel? Not enough Fuel? Exhaust Leak? Vent Blocked? Other?
To distinguish between having too much fuel or not enough fuel, the stove needs to be monitored prior to the build up.
If the Burn Pot slowly builds up with fuel, then it is probably getting too much fuel in the Burn Pot. The flame will also be slightly lazy and not quite as vigorous as normal.
If the flame oscillates and burns up most of the fuel in the pot, it is probably because there is not enough fuel in the Burn Pot. Half way through startup the stove will usually have a pretty small flame if this is the case.
Note that other problems can cause the pot to overfill or to burn poorly. These include: 1) dirty vent pipes (as discovered by Cargo); 2) raised feeder wheel (as explained by Blume98) in the following thread http://forum.iburncorn.com/viewtopic.php?p=78146 ; 3) improperly positioned top paddle caused by jamming on an obstruction such as a piece of hard clinker; 4) blocked vents in the burn pot or the top paddle; 5) leakage of exhaust into the input air due to an improper termination cap or to improper sealing of the inner vent pipe; 6) gasket leakage (e.g., under the burn plate and at the door); 7) incorrect moisture content of the corn or inadequate quality of the wood pellet http://forum.iburncorn.com/viewtopic.php?p=112116 ; 8) incorrect placement of the convection tube cover plates as discovered by Allynn (http://forum.iburncorn.com/viewtopic.php?p=123910). The rope gasket under the burn plates is an important leakage point to check. At the first sign of difficulty in tuning a stove, Millrtym13 seats this rope gasket in a fresh 1/8" bead of high temperature silicone as explained at http://forum.iburncorn.com/viewtopic.php?t=9530 .
Gasification with floating flames during ignition, dark cloudy purple flame, minor explosions, major explosions, etc. Explanation: If the stove cannot produce anything that looks like a proper flame, then it is very likely that some part of the exhaust venting path is filled to the extent that exhaust flow is vastly reduced. If this happens during startup, then it is possible that the igniters are gasifying fuel. If there is no self-sustaining flame, the igniters can ignite the gasified fuel, leading to very noticeable explosions. These are characterized by a loud bang followed by puffs of smoke that leak past the door gasket and the ash drawer gasket, but which is primarily vented through the intake and exhaust venting. Don’t allow the stove to run in this condition. Remedy: Thoroughly inspect and clean the stove. See the cleaning section.
Best Time to Adjust Trim Pots
From LET http://forum.iburncorn.com/viewtopic.php?t=6162: "You shouldn't make adjustments just after the ash dump. It is running its own special program while that light (red LED on the power board, inside the left side panel) is flashing. The best time to adjust the stove is just before the ash dump. That is when it is running the richest, so then you can get an adjustment that won't over fill the pot."
Resources for Optimizing Trim Pot Settings
Advice abounds on different techniques to adjust your trim pots. The more common techniques are posted here and above for you to study and to discover which works best for you. In addition to clicking on the 3 thumbnails here, see the Sticky thread on the Bixby forum at http://forum.iburncorn.com/viewtopic.php?t=787 and/or see LET's website at http://www.letenergysystems.com/page7.html . LET's site will teach you how to "read the flame" and to adjust accordingly. The flame will tell you what it needs. See user videos showing what a good and poor flame look like.
Quark (http://forum.iburncorn.com/viewtopic.php?p=135304) suggests using Bixcheck to determine optimum trim pot settings, as follows. "Pick a heat level, say level 4. Lean the stove out so you can see an oscillation in the flame (between feed dumps). You of course will be monitoring the flue thermocouple (TC) reading using Bixcheck software. Take note of the low and the high TC reading. Start to richen the flame to remove the oscillation as it should become less and less. You should also be noticing a smaller TC differential as you do this. When the flame becomes as consistent in height as possible, you should see the TC reading varying only a few points. This, to me, would be the best setting for the stove. Each time I came to look at the stove, I would create a chart from my data log – didn’t care too much about the numbers. I was looking for a straight line of the TC numbers on the graph. When it was as straight as possible, I felt the stove was tuned in. A graph is much easier and quicker to interpret then looking at bunch of numbers. Once you have a default graph set up, it only takes a moment to create. "
Lean Burn Overflow: http://www.scribd.com/doc/8842335/Lean-Burn-Overflow
Trim only the feed rate: http://www.scribd.com/doc/3168685/I-prefer-to-have-the-consumer-think-only-about-feed-rate-trim-pot-knob
Additional tips (Troubleshooting the flame): http://www.scribd.com/doc/3168695/Trouble-Shooting-the-Flame
External Factors
- Wind blowing towards your vent. The impact ranges from nil to significant depending upon your vent cap design, terrain, and wind speed. If it becomes a nuisance, construct a windscreen as in the following threads. http://forum.iburncorn.com/viewtopic.php?t=8295 and http://forum.iburncorn.com/viewtopic.php?t=5672&start=6 .
- Air density. The denser the air, the leaner your burn. It is governed by ambient temperature, and, to a lesser extent, barometric pressure and relative humidity. Click on the thumbnail for details on how to calculate the effect. It shows that a temperature drop from 32 degF to -4 degF increases air density by approximately 8% (i.e., leans the burn by ~8% or slightly more than 1 division of the trim pot) whereas a relative humidity change from 10% rh to 90% rh is effectively negligible for our puposes while a not-too-modest drop in barometric pressure decreases air density (i.e., enrichens the burn) by about 2.5% or slightly less than 1/2 a trim pot division. The stove can accommodate day-to-day meteorological variations without needing to continually tweak the trim pots. On the other hand, fellow perfectionists can take the above into account while exercising our pot-tweaking obsessions. See the following 2-page thread for more details http://forum.iburncorn.com/viewtopic.php?t=6438.
- Altitude. The higher the altitude, the lower the barometric pressure and the lower the air density and thus the richer the burn. For example, barometric pressure is approximately halved by an 18,000 ft increase in altitude. Note that the assumptions in the simplified air density formula, above, may break down over large changes in input parameters. See, instead, Wikipedia detailed calculations of Altitude Pressure Variation
- Height of your stack. The taller your vertical vent stack, the greater the draw and hence the leaner your burn. With tall stacks, you'll see greater variations in your burn as your draw changes; e.g., as your stack warms up.
Bixby Setup
The owner's manuals provide detailed setup information.
The following Bixby bulletin on venting locations (2007-09-14) is based upon revised NFPA requirements and supercedes the setup information in the earlier owners' manuals. Most notably, vents may now be located up to 1 foot from a window or door. http://www.scribd.com/doc/3168694/NFPA-Venting-LocationsRevised-20070914
In addition see below.
How to Move a Bixby Stove
It can be moved relatively easily on a 4-wheeled dolly or, on stairs, using a furniture dolly approached from the back of the stove. Use pads and don't strap too tightly. Lighten the load by first removing the side panels, ash pan, hopper door, burn plates, fire pot and heat exchanger panels. See http://forum.iburncorn.com/viewtopic.php?t=8347 for additional advice.
Clearances
Click on the graphic to view minimum clearances published by the factory.
Deflector
The deflector should be positioned so that fuel spreads evenly across the burnpot. For corn, the best setting is usually when the bottom of the deflector is centred over the burnpot. For lighter fuels such as wheat, it might be necessary to move the deflector forwards.
Procedure for replacing the fuel deflector: http://www.scribd.com/doc/3349959/Replacing-the-Fuel-Deflector-115-and-UBB
Convection Tube Cover Plates
Two convection plates (Model 115 & UBB) in front of the convection tubes deflect the exhaust in the burn chamber to travel up and over the length of the convection tubes then down the other side. This increases exposure of the hot exhaust to the tubes which helps to increase the efficiency of heat transfer.
These 2 rectangular stainless steel plates must be mounted on the 'ledge' in front of the heat exchanger tubes. They are held in place at the top by the pair of sliding scrapers. A common mistake is to instead place the convection tube plates on top of the burn plate so that the fuel drop pipe doesn't protrude past the baffle plates. They have been known to settle there during transport. As a result, fuel will accumulate behind the convection tube plates. This makes a mess and it restricts the amount of fuel that reaches the burn pot; thus affecting the burn.
Bixby guide on placement of cover plates (courtesy of Quark):
115 MaxFire and the UBB: http://www.scribd.com/doc/3349962/Replacing-the-Heat-Exchanger-Cover-Plates-MaxFire-and-UBB
100 & 110 Maxfire: http://www.scribd.com/doc/12470094/Convection-Tube-Cover-and-Burn-Assembly-PlacementModel-110
For the 100 and 110 MaxFire, according to LET: "...there are 3 plates and the outside 2 go in with the cut off corner to the top and outside & flanges out to you (smooth side in), then the center plate goes over those and is held in by a small bolt at the top." Incorrect placement of the cover pates can seriously affect your burn as noted by Allynn at http://forum.iburncorn.com/viewtopic.php?p=123910.
Air Diverter Plates
The air diverter plates install inside the top louver of the Maxfire. They help maximize the flow of air out of the stove by minimizing hot air being trapped between the stove top and a lip above the top vent. These plates are standard in stoves manufactured some time in 2006 and later. For some earlier stoves, the plates were missing but Bixby provided them under warranty through their dealership network. Click on the thumbnail at right for instructions on how to set them up.
Venting
Why Venting Rusts Out
Courtesy of Quark's Corner: http://www.scribd.com/doc/20887796/Why-Does-the-Venting-Rust-Out. Quark's article concludes with tips to help preserve venting:
1) Keep the stove in good tune (i.e., air/fuel ratio). 2) Keep the venting system as short as possible. 3) Use corn with moisture content less than 15%. 4) Run the strove at higher levels rather than lower levels. a. If you do need to run on lower levels, once in a while run the stove hot to burn the condensation in the venting out. The longer condensate with corrosive chemicals sits, the greater the damage it can do. 5) When using a direct vent system, make sure it is not drawing exhaust fumes back into the fresh air supply pipe. Any exhaust that returns in the intake pipe will condensate quickly as the temperature drop will be great. This will cause the condensate to attach to the walls of the venting and more likely settle at the bottom of the pipe, thus corroding the pipe.
To these tips, add the following: 6) At end of the heating season, clean the vent thoroughly then remove the vent cap, then cap the vent pipe (e.g., by tie-wrapping a plastic bag over it or by using a gear clamp to secure a plastic margarine container or the like over it.). 7) Install terminal horizontal sections of vent pipe on a slight downward slope to help drain condensation and penetrated rain.
Venting Constraints
Click on the graphic on the right for some factory guidance on venting. It includes run length equivalences for elbows.
According to JET http://forum.iburncorn.com/viewtopic.php?p=126698: "The Bixby plant had pipes 32' tall. Now the bad part, the pipe probably won't last very long. I would look at burning pellets if you are going to run a stack that tall, it won't kill the exhaust pipe nearly as fast."
Longer vertical runs will cause greater variation in draft. The stove might therefore require more frequent air/feed rate adjustment, especially after startup as the stack heats.
Note that the Bixby stove features a covered knock-out in the back to permit conversion to separate air intake and exhaust venting as in the setup by Belenus featured at http://forum.iburncorn.com/viewtopic.php?t=8225 . Check with your Bixby dealer and your insurance company before installing a non-standard vent design.
Vent Cap
As of approximately 2007, Bixby introduced a 3rd generation design of vent cap. It is made from AL29-4C stainless which withstands corrosive corn exhaust the best. DLS ( http://forum.iburncorn.com/viewtopic.php?t=8118 ) describes this new design as follows: "Yes, it's solid on the end. The exhaust vents out slots around the circumference, and the intake air is pulled in from slots on the back side. It is also unpainted." Jammer ( http://forum.iburncorn.com/viewtopic.php?p=98916 ) states that the tapered design draws air away from the house like a venturi.
Bixby Technical Support Bulletin- AL29 Vent Cap: http://www.scribd.com/doc/3153052/TSB001-AL29-Vent-Cap
Infinger2008 (http://forum.iburncorn.com/viewtopic.php?p=102772) explains that the termination cap separates the exhaust and fresh air using a cone inside the cap. This cone is held on with tabs and some caulking. The caulking seal can be broken during forceful installation. Check your cone and recaulk as necessary if you have trouble running your stove. Click on the thumbnail at left to see a disassembled vent cap showing a separated cone needing caulk; courtesy of Jawquin.
Vent Corrosion Quark's detailed explanation of why vents corrode and how to minimize it: http://www.scribd.com/doc/20887796/Why-Does-the-Venting-Rust-Out.
Connection to Furnace Plenum
The UBB, in particular, could, in theory, be readily connected to a furnace plenum with minimal tinwork. However, this might be in contravention of most codes, insurance requirements, and furnace warranties. Furnaces are generally tested and spec'd for normal cold air return temperatures. Check your local codes, insurance requirements, and furnace warranty before connecting ANY heating device to your furnace. Rather than make a direct connection, consider simply installing a cold air return in the same room as the Bixby stove. See Quark's advice at http://forum.iburncorn.com/viewtopic.php?t=11228.
Tips
If ice accumulates on the vent cap during the winter, simply run the stove on high until the ice clears.
Seal all joints in your vent carefully using red high temperature silicone. Leaks will create a "short" between your exhaust and your air intake, affecting your burn and longevity of your vent pipe and converter box in particular.
Click on the picture on the right to see a partial blockage of a vent pipe caused by excess silicone sealant at a pipe joint. The lesson here is to wipe down all joints before the silicone cures. Use a rag on a stick or other suitable jig. http://forum.iburncorn.com/viewtopic.php?t=8295. In the same thread, LET states that the silicone bead should be applied at least 1/2" from the end of the pipe so that the caulking doesn't squeeze into the pipe.
Tip: Do not seal your vent cap. You will need to remove it easily for periodic cleaning of your vent and light leakage is no issue as the vent cap is outside and open/venting anyways.
Tip: Do not screw your vent cap to your pipe. This could dimple the vent and cap together, preventing removal of the cap, as advised by DLS in the following thread: http://forum.iburncorn.com/viewtopic.php?t=7647&start=30 .
Tip: Avoid clear adhesive silicone sealant. The bond may well be permanent as reported at http://forum.iburncorn.com/viewtopic.php?p=142249 by teosinte. Not even a strap wrench could turn the pipe.
Tip: To unseal a joint, JET advises that it be deflected to one side then held there for a fraction of a minute until the seal breaks. Repeat by deflecting in a different direction until the seal is completely broken. If that doesn't work, MaryB suggests using a propane torch to soften the joint's seal. You can also try immediately, with gloves, after running the stove at a high temperature. Corny was able to unseal a joint at the converter box simply by using vibration as discussed at http://forum.iburncorn.com/viewtopic.php?p=142249.
Tip: You may apply high temperature silicone sealant to a hot pipe http://forum.iburncorn.com/viewtopic.php?p=109682 .
Tip: Install outside horizontal vent pipes on a slight downward slope to expel any condensation.
Tip: When burning for prolonged periods at heat level 1 or 2 when at higher risk of condensation, run your stove periodically at a higher temperature to burn off any condensation.
Pictures of a Setup
The forum.iburncorn.com Bixby forum shows many excellent photographs of stove installations such as the step-by-step set posted by simmerda at http://forum.iburncorn.com/viewtopic.php?t=11311. Click on the thumbnail for an enlarged image of the finished installation.
Benefits of Cleaning
http://forum.iburncorn.com/viewtopic.php?t=2532&postdays=0&postorder=asc&start=45
This post began in the following thread authored by Pstores. http://forum.iburncorn.com/viewtopic.php?t=3386 . See the Pstores thread for additional details.
Here's temperature measured at the front of the grill during a ramp up from temperature setting #1 to #8. 2 runs were done before a cleaning. Some of the side holes in the burn pot were crusted over before the cleaning. The air holes in the lower paddle were all clear before the cleaning. The vent was cleaned, too, but yielded only a few tbsp of soot. Heat exchanger was cleaned thoroughly. The 3rd run was measured after cleaning.
Green Slime Mystery Solved (from iburncorn forum)
[from post at http://forum.iburncorn.com/viewtopic.php?t=3678]
There have been reports of deflectors and burnpots developing a green coating, sometimes of a slimey texture, other times quite firm. One explanation is that the green coating is sulfur dioxide <math>SO_2</math> infused sugar. The <math>SO_2</math> attaches to the starch(ie: sugar) in the corn. Different varieties of corn have different amounts of starch. Generally, higher levels of starch is not ideal for burning. Higher moisture is also conducive to more starch, and more SO2. Sulfur is naturally green, thus the color. Sugar doesn't burn, thus the accumulation. It all makes perfect sense now!
Bottom line for us corn burners...green is bad!
Bixby Maintenance - How to (from iburncorn forum)
See also the general WIKI page on Cleaning for tips on stove cleaning.
Once a week
- remove the convection plates that cover the exchanger tubes, run the scrappers up and down about 4 or 5 times.
- Take your vac and clean the bottom of the tubes and the plate around the burn pot, you can also clean the glass at this time.
Video of Scoops' weekly cleaning: http://vimeo.com/2720094 (password= bixby)
Once a month
- do the above plus remove the plates around the burn pot and vac out the area around the pot.
- Remove the 2 spring clips that hold the pot in and lift out the pot, look at the small holes in the bottom of the pot, if any have ash in them take a 1/8" drill bit and push through those holes.
- Put the stove back together, close the door & hit the On button.
Bixby Maintenance - Schedule
Ok, KT, here is the maintenance and cleaning time tables from the newest owners manual:
- Fire Pot: Sidewalls brushed monthly, keep holes clear.
- Ash Drawer: Empty as needed.
- Heat Exchanger Tubes: No mention of frequency
- Exhaust Venting: At least yearly.
- Exhaust Fan: Once per year.
- Exhaust Manifold: Yearly. (this is cleaning around/behind the heat exchanger tubes)
- Fuel Hopper: Monthly
- Glass: As Needed.
- Feeder Tube: Monthly.
- Lower Paddle: Monthly.
- Air Filter/Compressor: Inspect Annually.
- Room Air Filter: Check monthly, replace every 2-3 months.
You guys with experience, please add to this with good hints and tips. This was pulled right from the owners manual. It seems It's a monthly and yearly schedule. I will probably do monthly stuff every 2 weeks, and yearly stuff twice. ---
To clean burn pot, deflector, and heat exchanger baffles, simply soak them in water for 30 minutes or so. They'll come out squeaky clean with no scraping or scrubbing. ---
Here's a tip from Corny for cleaning the drop pipe. Clamp a capped 1.5" rubber connector to it, filled with water as discussed in the following thread. http://forum.iburncorn.com/viewtopic.php?t=4202 . The 1.5" rubber connector will be a bit oversized for the pipe but it can be scrunched down enough to hold. Soak the end of the pipe in water like this for about 30 minutes, and it will come out clean with no scraping.
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To clean the hot glass without shutting down, Belenus uses a rubber scraper fashioned from a piece of used feed wheel gasket.
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Heat exchanger tubes Here's a tip from LET on cleaning behind the heat exchanger tubes http://forum.iburncorn.com/viewtopic.php?p=76663: "You can make a cleaner from a metal coat hanger, cut a piece about 10" long and bend a 90 on one end about 1" long then bend a 90 on the other going the opposite direction about 2" long. Take the plates off, get your vac and put it right up to the tubes and using a flash light to see, put the small bend through the tubes and start reaching way back up in the collector and pulling soot down to the vac."
Regarding the heat exchanger tubes, JET suggests spraying them down with WD40 or some other corrosion protectant after the final Spring cleaning. He says most of the corrosion of these tubes occurs during the summer. Scoops uses Pam spray; smells nicer.
According to Steadywoman, some model 110 Maxfires are equipped with an 1/8" plug for blowing out the heat exchanger tubes. It is on the left side of the manifold, behind the air duct. One might have to disconnect the duct to get to it. Use low pressure (15 psi) air to blow it out, then clean the exhaust fan. This is supposed to be part of the yearly clean up. For stoves lacking a 1/8" plug, Blume98 advises in the same thread that the area can be blown out as follows. "You could take exhaust fan cover off, then stick an air nozzle up the vertical pipe. Jam rags around it and blow. Dust will come out ash pan. Some of it can be messy. I have also blown out exhaust pipe that had 90 then 7ft straight up pipe by sticking nozzle in past ex fan blades."
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Miscellaneous cleaning tips
Here's some year end maintenance tips from Corny:
- Tighten the 3/16" Allen screw that connects the ashdump arm to the ashdump motor cam. It's right on top of the ashdump motor, easily accessible from inside the left side panel. Mine detached after 3 seasons of normal use.
- It isn't necessary to clean out the exhaust fan every year. It's OK to do it every other year because very little soot accumulates there in normal use. On the alternate years when you do not open up the fan cover, at least loosen and then retighten the fan cover screws. They tend to seize otherwise. On the years that you do clean out the exhaust fan, be very careful with the exhaust fan cover gasket. The original design is very flimsy and easy to tear; the screw holes are almost the width of the gasket itself, leaving very little "meat." The newer design is foil backed and somewhat less prone to tearing.
- To prevent rain from entering your exhaust and causing corrosion during the off-season, remove the vent cap and cover the pipe. An empty Crisco shortening tub fits snug nicely over the 5" pipe. You could instead tie on a plastic bag. If you do block the pipe, unplug the stove and attach a reminder note to the stove's power cord or other prominent place to prevent inadvertent operation while the cap is covered.
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Bixby Guide to Cleaning the 110 Exhaust Manifold: http://www.scribd.com/doc/3144260/110-Cleaning-the-110-Exhaust-Manifold
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Tip from Quark ( http://forum.iburncorn.com/viewtopic.php?p=96836 ): Do not oil the bearings of any Bixby fan or motor. They are all sealed and impregnated with grease. If they are loud, they are defective, so replace them. Update from Quark: some of them have sleeve bearings that can be oiled with difficulty. See http://forum.iburncorn.com/viewtopic.php?p=140529 for instructions.
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Magnum uses Q-tips and gun cleaning solvent to clean the exhaust fan blades ( http://forum.iburncorn.com/viewtopic.php?t=8206 ).
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To clean the airwash, Uffda suggests "Take a eight or nine inch knife, slide it back and fourth through the slot inside the stove at the bottom of the door. Anything blocking the air wash will fall in the ash pan. Simple and fast and glass says clean longer."
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Feeder Wheel
There should be no corn or debris under the feeder wheel. It should sit flat. If not, remove the feeder wheel and clean out the debris under it. To prevent this from occuring in the future, clean out the fines at the bottom of your hopper periodically. If you are burning pellets, ensure that they are all short enough for the feedwheel to pick up and deliver. Otherwise, they will build up in the hopper and could be forced up and behind the feedwheel. During the 2008/09 heating season, be especially wary of the Greenwood brand of pellets packaged on 10/2007 and 3/2008. They are reported to be recalled due to excessive length. http://forum.iburncorn.com/viewtopic.php?t=8568 . It has also been reported in 2009 that the length of pellets (up to 1.5") from Curran Renewable Energy in Massena, NY, caused similar problems.
Feedwheel Malfunction with Error Code 8.
Click on the thumbnail (above right) for the troubleshooting procedure proposed by the factory. Issues covered include jambing, feedwheel motor, feedwheel sensor, snap disc, and wiring.
Ref.: http://www.scribd.com/doc/3155819/Feed-Wheel-Does-Not-Operate courtesy of Quark's Corner.
Noisy Feeder Wheel
If noisy, remove any debris under the feeder wheel.
From Rox5488 http://forum.iburncorn.com/viewtopic.php?t=7231: "...check your feed wheel cover plate. Sometimes they get a bow in the middle and the plate will rub on the top of the feeder wheel hold down bolts. This is easily seen if you take the feed wheel cover off. Look under there for some scratches in a circle in the center. If that is it, bend the feed wheel cover the other way a little."
Feeder Wheel Removal
Remove the four 5/16" screws on the 4 corners of the feeder wheel shield. Then, using a 1/8" Allan key, remove the 4 screws near the centre of the feeder wheel. These are the screws with springs on them. Do NOT remove the large nut in the centre. It would need to be retorqued. Ref: http://forum.iburncorn.com/viewtopic.php?t=2577 and http://forum.iburncorn.com/viewtopic.php?t=5609 and http://forum.iburncorn.com/viewtopic.php?t=7581.
Feeder Wheel Gasket
The feed wheel gasket 1) "levels" off the fuel in the feed pocket for a consistant burn, and 2) seals off the feed tube during the feed, or power outage, to keep fire from entering the hopper. If the underside of your hopper lid is black with soot, then the gasket has likely leaked. To inspect the gasket, remove the two 5/16" screws that hold the gasket plate in the centre of the feeder wheel cover. If it is badly worn, it may be turned over by drilling out the rivets and replacing with a pair of washers and 1/2" #8 self tapping screws as discussed in the following thread http://forum.iburncorn.com/viewtopic.php?t=5115&postdays=0&postorder=asc&start=36 and shown in the first photo. If gasket wear is a recurring problem, straighten the tab in the gasket backer plate as shown in the second photo with a reversed gasket. In this photo, one can just see in the rear that 1" self tapping screws were used in place of the rivets. These are too long, limiting the travel of the spring loaded backer plate and partially defeating the tab-bending fix. 1/2" screws were eventually used here.
Bixby procedure for replacing the feeder wheel gasket:
Click on the 2 thumbnails at left for details, or download the following document courtesy of Quark's Corner. http://www.scribd.com/doc/3349948/Replacing-the-Feeder-Wheel-Silicone-Seal-115
Belenus designed a variation of this loop gasket featuring a retainer bar. See his post at http://forum.iburncorn.com/viewtopic.php?t=8106 for other photos and details on how to construct it. His gasket material was purchased from http://www.chiefaircraft.com/airsec/Aircraft/Weatherstrip/BaffleGasket.html, Part # - QIP S8071B RE.
Feeder Wheel Replacement
Bixby Guide to MaxFire and UBB Feeder Wheel Replacement http://www.scribd.com/doc/3349954/Replacing-the-Feeder-Wheel-MaxFire-and-UBB
Bixby Guide to 110 Feeder Wheel Replacement: http://www.scribd.com/doc/3153026/110-Feeder-Wheel-Replacement-Instructions
Feeder Wheel Tension
Bixby Guide to Setting 115 Feeder Wheel Tension: http://www.scribd.com/doc/3153049/115-Setting-the-Feeder-Wheel-Tension
Enerjet ( http://forum.iburncorn.com/viewtopic.php?t=8447 ) cautions us against overtensioning the large feedwheel nut or by placing washers over the feedwheel mount springs. This can damage the feed motor and mounts. He notes that tension at the centre nut can be lost over time due to the rubber feedwheel motor mounts taking a set. The feedwheel springs do not lose tension and needn't be tampered with. You might not necessarily have had to have removed the center nut previously to have lost some feedwheel tension at the centre nut. Suspect tensioning problems if you have a chronic problem of fuel accumulating under your feeder wheel despite frequent cleaning under it. Ashdump suggests, in the same thread, that excessively long pellets can contribute to such accumulation problems. To tighten the feedwheel, Enerjet says http://forum.iburncorn.com/viewtopic.php?p=133816 "the feed wheel, not the feed wheel lock nut, gets turned 1.5 turns after it touches. If you went more, there would be too much tension on the feed wheel, causing it to drag and set the #8 Error . The lock nut is tightened afterward to lock the feed wheel adjustment in place."
Feeder Wheel Motor Replacement
Reasons for replacing the feeder wheel motor can include: 1) wheel doesn't turn and the #8 LED light is blinking; or 2) the feeder wheel motor jams often or doesn't turn at all even though it isn't jammed.
Bixby Guide to Replacing Feeder Wheel Motor- MaxFire & UBB: http://www.scribd.com/doc/3349941/Replacing-the-Feeder-Wheel-Motor-MaxFire-and-UBB
Feeder Wheel Sensor Replacement
The feeder wheel sensor is located under the hopper. It has red, blue and black wires.
Bixby Guide to Replacing Feeder Wheel Sensor - Model 115: http://www.scribd.com/doc/3349944/Replacing-the-Feeder-Wheel-Sensor-115
Convection Fan
The convection fan mounts under the fuel hopper. It pulls room air through an air filter into the stove where it is warmed at the heat exchanger then moved into the room at one of the highest rates known in the industry for freestanding stoves (530 cfm free-air rating, 275 cfm as mounted). The fan is of a backward curved "motorized impeller", capacitor start, capacitor run design noted for very high quality. It is brushless with long life dual ball bearings and with auto-resetting thermal protection set to activate at 104 ºF. Its 115 Vac motor is totally enclosed, thereby staying clean for long life operation. The fan speed is governed electronically from 25% to 100% of the 2550 rpm rated maximum. This is done through readings from the flue thermocouple in accordance with a speed-to-temperature profile that can be adjusted through BixCheck Software. Prior to approximately 2006, Bixby stoves were manufactured with a quieter but less efficient version of the same fan. It is rated at only 1700 rpm. This might explain the differences in fan noise perceived by different Bixby owners.
Fan too Loud?
Exhaust or Convection Fan? If your convection fan is too loud for your tastes, first be certain that your convection fan and not your exhaust fan is offending. To check, temporarily manipulate your exhaust fan trim pot between the -5 to the +5 settings. If the sound changes immediately, then the culprit is most likely the exhaust fan. Alternatively, you can temporarily pull the exhaust fan connector at J13 on the bottom half of the motherboard. If the sound persists, then your convection fan is most likely to blame. That can be confirmed if the sound disappears when temporarily pulling J12 at the bottom right corner of the motherboard. Warning: be careful when inserting your hands into the cabinet while the stove is operational. There is a danger from shocks and rotating fan blades.
Silence vs. Efficiency To move a high volume of air out into the room where needed while keeping the stove cool to the touch, no fan can be completely silent. There will be a "swoosh" sound of moving air, increasing with the flue thermocouple readings. While subjective tolerances for sound differ between people, most but not all Bixby owners find the "swoosh" to be acceptable and perhaps even soothing in the knowledge of all the money saved by that moving air, whether using the 2550 rpm or the 1700 rpm fan. Some report that they can easily watch TV while only 10 feet away from their stove with its convection fan spinning at the maximum 2550 rpm. Others are clearly disturbed by the 2550 rpm fans when the stove is operated at the highest heat levels. Using a sound level metre, DLS reported sound level measurements from his stove that are essentially the same as from his refrigerator at the same distance, and significantly less than the sound level from a normal conversation with his wife http://forum.iburncorn.com/viewtopic.php?t=2532&start=15 . His measurements were taken with his fan running at or near maximum speed. His fan is believed to be a 1700 rpm model, but that remains to be confirmed.
The swoosh sound is normal. It may be mitigated by:
- operating your stove at lower heat levels and hence convection fan speed; or
- using Bixcheck software to reduce the fan speed as a function of flue temperature (try a "TC@25%" setting of 20 and a "TC@100%" setting of 255), or
- extracting the flue thermocouple by 1/4" or so to reduce its readings, or perhaps
- installing a stepdown transformer ahead of the fan (it is estimated that a 115V-to-80V transformer of at least 200 VA rating will slow a 2550 rated rpm fan to that of a 1700 rated rpm model; an alternative might be a 115V-to-175V stepup transformer connected in reverse); or perhaps
- installing a ceiling-fan speed control ahead of the convection fan; or
- rearranging your furniture to better separate incompatible activities.
Squealling, rubbing, grinding and shaking sounds are abnormal. They are indicative of:
- bearing failure or;
- vibration caused by imbalance or loose mounting of a stove component.
These faults can be corrected by 1) removing and replacing the fan or its motor or its bearings, or 2) tightening all loose components. From [Blume98]: I had one making a very shrill noise. This was a new stove. It was coming from the convection fan area. When I pushed on the housing, the noise would stop. I loosened all 4 screws holding the fan assembly. I shook it around then retightened. Noise GONE!
Convection fan is stopped or intermittent
The convection fan should run continuously during stove operation. Otherwise...
- Check that it really is stopped and not just slowed down. LET advises http://forum.iburncorn.com/viewtopic.php?p=78511&start=13 :"At slow speeds it can sound like it is off because its hard to hear it running. If is does actually stop then it is a defective fan and will need to be replaced. Take off the left side panel and use a flash light to see if the fan has stopped. If the fan does stop, the top of the stove would get very hot; and if it gets too hot the high temp cut off will shut the stove down (with a #3 error)."
- Check out the fan's bearings as discussed by LET http://forum.iburncorn.com/viewtopic.php?t=2854 : "Now if your convection fan quit then the stove might see a exhaust temp rise and think it had a blocked flue. Open the left side of your stove, UNPLUG it, then see if the convection fan spins easy, its the one right under the hopper. If the fan stops fast when you spin it then the bearings are bad. If that is the case contact your dealer and have it replaced. "
- Check electrical connections as discussed by Scoops and DLS http://forum.iburncorn.com/viewtopic.php?t=6325 :"Might not be securely plugged into the motherboard. Trace the cable from the fan to the board, unplug, and re-seat. If you look in your manual it will tell you where it plugs into the main board." "The connection at the mother board is J12, lower rt. corner. There is also a capacitor in the harness to the fan, and a ground, I think. Verify all these connections, and then check the fan, may be defective."
- The convection fan can shut down if overheated. Check that the air filter is clean. See http://forum.iburncorn.com/viewtopic.php?t=7300 about the perils of using an air filter that is too thick and thus restricts air flow. Remove the side panels and/or the air filter as an interim or troubleshooting measure.
From Tomorokoshi http://forum.iburncorn.com/viewtopic.php?t=7300:"The convection fan has a built in thermal cutout switch. The convection fan has two heat sources: the electric motor, and the back of the fire box. The cutout switch is designed to turn off power to the fan when something happens to it. In this case, a well running stove shut it down. The things to look for in this situation are: 1) Air filter starting to get clogged; 2) The room at a higher temperature - meaning the inside of the stove is also high; 3) The fan speed settings set lower than they could be. If the fan was not already at 100% you can increase the speed a little (via Bixcheck) to help cool it down. This may prevent this problem... In the meantime, leaving the side panels off may help. A box fan on low can blow a lot of heat out too."
From Mary B : recalculate the fuel tables using Bixcheck.
From a draft service manual found in Quark's Corner: "The convection fan (uses) a (10 µF) capacitor to start and run. There are two windings in the motor, one is called the starting winding and the other is called the running winding. ... The capacitor with this motor is used to start and run the fan by creating an electrically magnetic phase shift between the running winding and the starting winding. The capacitor allows the motor to have higher starting and running torque. If the capacitor were to be removed or to fail while the motor were running, the motor would stop. The capacitor is sized by the manufacturer to match the starting and running characteristics of the motor. If needed, the capacitor must be replaced with a capacitor that has the same ratings in voltage and capacitance." The capacitor is the large white canister mounted on the bottom of the igniter board. Procedure for replacing the capacitor of the Maxfire convection fan motor: http://www.scribd.com/doc/3349978/Replacing-the-MaxFire-Convection-Fan-Motor-Capacitor
Convection Fan Removal
As reported by Scoops in the following thread http://forum.iburncorn.com/viewtopic.php?p=69627 ...
"... (It's) easy to take off, trust me, I've done it now about 3 times removing it while swapping out exhaust fans. There are 4 bolts that hold the convection fan, an additional 2 that come down from the hopper (you'll need to unscrew them just enough so that the convection fan can clear them). Remove the two purple wires that connect to the door sensor, then unplug the two brown wires that connect to the side of the outside of the manifold shield. Unplug the ignitor wire so its not in the way, probably do the same for the thermocouple (red side towards you). Then you will have to remove the three wing nuts that hold the control board move the control board back about an inch or two, then that sucker will slide out with a little finesse. This procedure will also allow easy access if you ever have to remove your exhaust fan. Thanks to LET for leading me this way to get at the fan."
As reported later by Scoops http://forum.iburncorn.com/viewtopic.php?t=10417: "When you remove the fan, there are also two screws in the hopper that you should back out most of the way, they are the middle screw on each side. You will see how they interfere with the removal of the convection fan. You should also disconnect the door switch (2 wires) and snap disc( 2 wires) so that they do not get in the way when you have to slide the fan out. Make sure you remember to connect them back up once the new fan is installed. Also when you disconnect the ground, there are two more wires that run into the cap that will need disconnected, label them, one is brown and the other is black."
From Ashdump http://forum.iburncorn.com/viewtopic.php?t=7300&start=18: "The task at hand was pretty simple but have to be very careful not to damage computer board when pulling out convection fan housing. There is also a screw on the exhaust side of the stove that is a MAJOR PAIN IN THE A** to get at to detach the housing. I had to unclip all wire ties to loosen the wires for room so the convection fan could come out. Definitely was not able to put everything back the way the factory did though!"
From Bioburner re. replacing convection fan for model 110 http://forum.iburncorn.com/viewtopic.php?p=94782: "Instead of removing the feed wheel motor, I loosened the computer board (four bolts) and loosened the back cover of the stove and just took the fan out the rear of the stove. It was a tight squeeze to fit the fan past the feed wheel motor, but possible. This seems a little easier than removing the feeder wheel and motor."
[From ID Farmer]: "It slides out the left side of stove. Need to disconnect any wires in the way and maybe cut a few zip ties. Remove fan wires from board and you will have to remove filter and unhook the ground wire. Also need to remove the three wing nuts holding the boards and move board back towards where the filter was. There are 4 screws that hold the convection fan housing in place. They screw into hopper. The one that is a pain is on the exhaust fan side behind a tube that goes from convection tubes to EFan. I used a 3/8" ratchet, 3/8" to 1/4" adaptor, 4" long extension, and 5/16" socket. Seemed to get in there and remove the screw with no problems. To reinstall I put a dab of grease on the 5/16" socket to hold the screw in and started it by hand without the ratchet attached. Once started I then used ratchet to tighten. The other three screws I just used a nut driver. "
Bearings
Bixby advises against lubricating fan bearings. They are maintenance free ball bearings. If they squeal or seize, the fans should be replaced. Nevertheless, Oldschool reported success in resurrecting a seized convection fan motor bearing as follows http://forum.iburncorn.com/viewtopic.php?t=10084&start=15: "This motor can be taken apart rather easy. Pull the dust cover and pull a small snap ring and apart it comes. The bearing near the fan hub was frozen. ... I sprayed some WD40 on the bearing and it loosened up. I then drilled a small hole through the side of the bearing and used a syringe to fill the bearing cavity with grease. ... I packed grease in the area between the dust cap and the bearing. The bearing is marked a SKF bearing BB1-0608BD."
From [ID Famer]: "The old (defective) bearings showed no sign of failure. The fan was tight, and spun freely. Also the same thing here on the noise. It started just noticeable to slowly getting louder and louder. Only difference, maybe because I changed them right away, the noise was only at lower settings. At upper fan speeds it went away or maybe was partially covered up by the swish sound of moving air."
From Blume98 on replacing the fan motor bearing http://forum.iburncorn.com/viewtopic.php?p=123140: "...you take out silver cap with a pick, small hole ok, there is a C clip, remove it and fan comes apart, replace bearings and reasemble, if you use sealed bearings you would not need cap, if you do a dab of red rtv sealer on hole will close it, i have a fan coming back to me and will do it myself as soon as it comes, i got 8 brgs for 15.00 on line, they are skate board brgs". See this thread (above) for photos and additional discussion. See also http://forum.iburncorn.com/viewtopic.php?p=126460 for discussion on GKramer's repair job and alternate source of supply for bearings.
Annotated photographs from Scoops on bearing replacement: http://forum.iburncorn.com/viewtopic.php?p=131266.
Converting to New Style Convection Fan for the Model 110
From Quark (http://forum.iburncorn.com/viewtopic.php?t=7766 ): "Make sure you change out the capacitor. The 110 fan (orange) used a 6uf capacitor. The 115 fan (Black) needs to use a 10uf capacitor. As for the axial fan, if you replace it try to find one with metal blades as they seem to run quietier and when the stove is reprogramed, it is pulsed the same as the convection fan. Not all of the axil fans will have a noise problem. Before changing it out, try it first. The reason for the reprograming: The 110 used a four speed motor (5 wires) in which one speed was energized at a time ie: low,medium, medium high and high. The axial fan is tied in with the high speed winding. So the axial fan only ran when the convection was running at high speed.The four outputs on the fan plug are turned one on at a time and all at a steady 120 volt.
The 115 (black) fan is a single speed fan and gets wired to the high speed plug. By reprograming the stove, the high speed pin gets controlled the same way as the 115, basically on and off twice every cycle. If you do not reprogram, the convection fan would only run when the stove would normally call for high speed and the would run at full high speed. The control of the convection fan is very similar to a speed control for a ceiling fan."
Guide for replacing convection fan capacitor: http://www.scribd.com/doc/3349978/Replacing-the-MaxFire-Convection-Fan-Motor-Capacitor
Replacing Convection Fan Motor
Model 110: http://www.scribd.com/doc/3349893/Replacing-the-Convection-Fan-Motor-110
Model 115 (s/n 5000 to 9800): http://www.scribd.com/doc/3349901/Replacing-the-Convection-Fan-Motor-MaxFire
Model 115 (s/n 9800(+) & UBB): http://www.scribd.com/doc/3349896/Replacing-the-Convection-Fan-Motor-MaxFire-9800-and-UBB
Procedure for replacing the capacitor of the Maxfire convection fan motor: http://www.scribd.com/doc/3349978/Replacing-the-MaxFire-Convection-Fan-Motor-Capacitor
Convection Fan Won't Shut Off
The convection fan should always be on during stove operation. When the fire extinguishes and the flue cools to an acceptable level, the convection fan should shut off. There are at least two isolated reports of the fan not shutting down when it should. Little is known for sure of this problem reported by jrtstoves and Blume98. For the time being, see the discussion at http://forum.iburncorn.com/viewtopic.php?p=150695 which speaks of such possible issues as 1) software error due to power surge, 2) thermocouple issues, and 3) other parasitic voltages. Blume98 reported in the same thread success in curing the problem by reloading the software using Bixcheck software.
Exhaust Fan
General
The exhaust fan uses a 2 pole "squirrel cage" motor with a 3000 rpm name plate rating. Its speed is controlled by switching the on-time at different degrees in the sine wave rather than by voltage attenuation. A fan sensor (i.e., tachometer) provides feedback to the stove's exhaust fan speed control system.
Exhaust Fan Problems
Fails to Run: From Tomorokoshi http://forum.iburncorn.com/viewtopic.php?t=5782 : "I've pulled most connections while it is running without any problem. You should be able to do it. Just be careful in there; those connectors are not the easiest things to get off. Check the crimp of the pins on the wires. The resistance of the motor is around 9 ohms. A clamp-on ammeter would help a lot. The motor draws about 1A at full power, so a high-capacity (clamp-on) ammeter might need a few turns of wire (you'd then need to divide the reading by the number of turns). The fan might run when the door is open. The system ramps the control signal, so it might not kick in right away. "
From JET http://forum.iburncorn.com/viewtopic.php?t=5782 : "I don't remember the exhaust fan being thermally protected. I wonder if there is a problem in the winding and the heat is causing it to short out?"
If the exhaust fan stops without a #6 error, suspect an incorrect exhaust fan setting in the stove's calibration fuel tables. In one bizarre case reported by Logger (http://forum.iburncorn.com/viewtopic.php?p=127709#127709) the exhaust fan would stop during ash dumps without a #6 error. Without adequate air, the flame became difficult to sustain, and this was aggravated by smoke leakage into the room. The problem was traced to a combination of 1) a worn feedwheel gasket (hence the smoke) and 2) an incorrect ashdump fan setting of zero. The problem was corrected by increasing the ashdump fan rate using Bixcheck software.
From jhetrick62: I had (an overheating) problem after updating to ver 2.71 of the software where the LB Fan was set at -100 which shut the fan down completely when a Lean Burn started to adjust. This caused a very hot top and smoldering in the feed bin.
#6 Error but Exhaust Fan Still Runs
See http://forum.iburncorn.com/wiki/index.php/Bixby#Light_.236
Noisy
After checking that it is mounted securely, check that it is clean. Excess soot on the blades can throw it out of balance. To access, carefully remove the fan cover on the right side of the stove. See warning, below, about fragile fan cover gasket. Next, check that the speed sensor isn't touching the rotating fins. If none of these checks work, then replace the exhaust fan.
From LET http://forum.iburncorn.com/viewtopic.php?p=89059: "If you can hear a noise when you spin the fan by hand it may be the speed sensor on the exhaust fan is hitting the cooling fan fins. I have had a couple of stoves like that. You just have to bend it back a little. Other wise it is probably an out of balance motor. ... It's on the back side of the box on the motor. Its just below were the tube from the stove mounts on top of the box. You can feel it with your hand. If the stove is on be careful, ITS HOT." From Scoops in the same thread: "That rpm sensor is held on by two nuts. you can get access to it from the left hand side of the stove, its tricky, but you can do it."
From Tomorokoshi in the same thread: "The fan sensor picks up a secondary fan blade just behind the main housing. It is mounted to the fan housing by a yellow chromate bracket with two screws. If the sensor is hitting the blade, there will be a definite metallic sound. The sound will probably hit for two or three fins per revolution and then miss the rest, although it's possible for most of them to hit. While it is difficult to see, there is generally not a reason to pull out any of the motors. As you seem to have found it, the easiest way to adjust it is to bend the bracket back a bit. This method works if you are able reach in there - that is the difficult part. First, with the stove cool, open the door and get the fan motor running. From the exhaust side, push down on the sensor a little - not enough to bend the metal, just enough to flex it in. The noise should become louder if that is the problem. If you determine that as the problem, access to it is possible from the control board side. You can get a shot at it through the space between the back of the convection fan housing and the back of the firebox. However, the space to too small for you to actually do anything directly. Even though, you can feel the bracket and see how it fits in there compared to the rest of the assembly. A long, flat-blade screwdriver can get in there and be used to bend it up. This should be done with the stove unplugged. If you need to pull out equipment, I would recommend that you don't pull out the exhaust assembly. Instead, depending on how you can get things out, pull out the convection fan assembly. This may require that you also pull out the circuit board assembly and the the air pump assembly. However, while the convection fan is the hardest of those three, the exhaust fan assembly is more troublesome than all three put together." Scoops warns in the same thread that it is possible to bend the bracket back too far. When this happens, the sensor will not give the correct fan speed data and this will affect the burn. Also in the same thread, Den from PEI reported that he was able to make the adjustment using the 2 nuts that secure the speed sensor. [Bixby procedure for replacing the exhaust fan sensor]
From Rayburn11 ( http://forum.iburncorn.com/viewtopic.php?t=8255 ): "Exhaust blower making a rattling noise. ... I finally pulled the filter, then the air intake hose. Looks like it will come out the back and yes it will. 1/4" drive with three 8" extensions and it was out. Well the problem was the fan that cools the motor (i.e., cooling fins on the shaft of the fan) came loose from the nut that locks it to the shaft. ... It is a (model) 115, the fan is right in front of the motor locked on with set screw. "
Irregular Fan Speed You could have a loose thermocouple connection at J18 at the top part of the motherboard as explained at http://forum.iburncorn.com/viewtopic.php?t=9976 .
Fan Freewheels on the Shaft From Quark http://forum.iburncorn.com/viewtopic.php?p=121622: "This fan blade needs to be tight on the motor shaft so it does not turn on the motor shaft and is centered under the exhaust fan sensor. If this fan blade is loose or out of alignment, the stove will issue a #6 error code. This may be checked by gently holding the small fan blade with a popsicle stick or a small screwdriver. Use the exhaust fan blade (inside if the exhaust fan cleanout box) to gently turn the motor. If the small blade turns, it must be repaired or replaced. The causes of the small fan blade not turning with the motor shaft may be: 1) The set screw may be loose (5/64” hex head). 2) The blade may have become loose on the hub that it is mounted to. This may be repaired by removing the fan blade from the motor shaft and tapping the crimp on the hub to be a little tighter. 3) The set screw may seem tight but cross threaded. This may be repaired by removing the set screw and installing it correctly."
Fan Cover & Gasket
Warning 1: The fan cover gasket is flimsy and easy to break. Treat it like a lady. See http://forum.iburncorn.com/viewtopic.php?t=3072 .
These gaskets have improved since ~2007. They now have a foil backing to help keep them intact. They are also now less expensive and are sold by Bixby in a package (of 5?). LET suggests that they be installed with the foil side facing out.
Warning 2: The fan cover screws are prone to seizing in place. Careful that you do not break them. If seized, use a can of Aerokroil to free them up. To prevent breakage, turn them only with a 5/16" nutdriver so that you do not build up enough torque to break them. If you do break them, turn them from the backside using vicegrips.
Tip: Replace the screws with studs and wingnuts. Alternatively, JET says to just buy some screws and put them in from the back side. Then fasten the fan cover over them using wingnuts. They are 10/24 thread, available anywhere. According to Blume98, the studs and wingnuts are available from Fastenal part #1125222 #10-24 X1/2 or 3/4 and nuts part#1136028. See the multipage thread at http://forum.iburncorn.com/viewtopic.php?t=5858 for a discussion on this tip and above warnings. As another alternative, Bixby suggests that they be replaced with 5/16" long bolts from the front as in the following technical guide: http://www.scribd.com/doc/3349912/Replacing-the-Exhaust-Clean-Out-Cover-Screws-115. DLS explains that 5/16" is just long enough to grab all the threads without protrusion into the exhaust chamber. Whether studs or bolts from the front or back, he suggests that they be stainless. He prefers SS cap screws. If the threads are tight, don't force the new screw; it might break. S A M suggests cleaning out the threads beforehand with a 10/24 tap http://forum.iburncorn.com/viewtopic.php?p=131456.
Exhaust Fan Removal
From http://forum.iburncorn.com/viewtopic.php?t=5252&highlight=exhaust+fan+remove.
LET's method: "...you could remove the convection fan and then you could reach through from the other side (of the stove) and remove the nuts that hold the fan on. When you put the tach sensor back on make sure that it doesn't hit the cooling fins on the motor. After you put the motor and tach back on spin the fan from inside the collector box. If it hits then loosen the nuts move it out just a little. ... When I referred to taking the convection fan out and working from that side, you would not have needed to take the fan housing off the converter box. Just take off the nuts that mount the motor to the housing, remove the motor and put the new one back. That way you don't have to reseal the joint between the converter box and the fan housing."
Scoops' method: "I simply removed the 4 screws that connect the fan housing to the converter box, and lightly cut around the silicone to help make it easy to break away the two parts. This was a bit challenging but they will come apart, just take your time and do not over stress any parts. "
Note: Don't forget to carefully read the excellent instructions/schematics that come with the new fan package.
Exhaust Fan Replacement
Bixby Guide to Replacing Exhaust Fan - Model 115: http://www.scribd.com/doc/3349925/Replacing-the-Exhaust-Fan-MaxFire-115
In addition, see the procedure developed by Rayburn11 which he published in the following thread: http://forum.iburncorn.com/viewtopic.php?p=99143 .
Exhaust Fan Sensor
It is also called the exhaust fan tachometer. It gives the stove’s computer feedback as to the actual speed of the fan. It is also used to determine if the Exhaust Fan is working correctly. The Exhaust Fan uses this input to run an exact speed. Click on the thumbnail at right for a photo of the sensor, courtesy of Scoops. Other photos and chronicle of a repair job are available at http://forum.iburncorn.com/viewtopic.php?t=9999&start=30 .
According to Tomorokoshi on the sensor's approximate resistance, for diagnostic purposes http://forum.iburncorn.com/viewtopic.php?p=117937 : "... expect around 1000 ohms. If you don't get that, check the crimp on the connector. The sensor is the 2-wire one with the white connector. The feed wheel is the 3-wire one with the black connector."
To further test the sensor, bring its maganetic tip in close proximity to metal, thus simulating the presence of a fan blade. If the sensor is working correctly, its resistance should drop. See also #6 error and http://forum.iburncorn.com/viewtopic.php?p=127614.
Quark proposes yet another test as follows http://forum.iburncorn.com/viewtopic.php?p=133003. Disconnect connector J10 for this test. Connect voltmeter leads to the two sensor wires with the meter on the lowest DC millivoltage scale. The exhaust fan sensor is a non-contact ferrous metal (having the presence of iron) detecting device. The sensor is a HALL EFFECT transducer, which varies its output voltage in response to a changing magnetic field. Any ferrous metal will distort the magnet field and cause a voltage to show on your meter. Remove the exhaust fan cleanout cover and slowly spin the fan blade. Each time metal passes under the sensor your meter should show a small (milli)voltage either + or -. If you get no indication, look closely at the small fan blade on the motor shaft and make sure it is centered on the sensor. If you still get no indication of a small voltage, remove the sensor. With the meter still connected to the sensor, pass a peice of metal under the sensor. MAKE SURE THE METER LEADS ARE NOT TOUCHING EACH OTHER. If you still get no indication, the sensor is bad. BUT if you do get an indication of a small voltage, the sensor would be good and you would have to look further at the small cooling fan placement or if it loose on the shaft.
Bixby Guide to Replacing Exhaust Fan Sensor: http://www.scribd.com/doc/3349922/Replacing-the-Exhaust-Fan-Sensor-115. Note that GerryChuck (http://forum.iburncorn.com/viewtopic.php?p=127614) uses a different procedure for replacing and adjusting the sensor without removing the exhaust fan or any other components.
Ash Dump Irregularities
NOTE: If an igniter is burned out on the stove, the stove may not perform the ash dump.
Burn Paddles - How to Clear a Jam
As reported by LET in the following thread http://forum.iburncorn.com/viewtopic.php?t=1597&highlight=feedwheel&start=6 ...
"... unplug the stove, remove the left side panel (where trim pots are), there is a motor with the linkage to the paddles, on the back side towards the pots on the bottom of the motor is a tab that runs across the bottom of the motor, that is a brake, push it in and hold it, with your other hand turn the arm on top of the motor to back it away from the cookie. This will work most of the time without tearing it apart. Usually the cookie just drops out."
Also relevant discussion by bobbr1 at See also http://forum.iburncorn.com/viewtopic.php?t=787&start=21 .
Dump cycle jams, produces elliptical clinkers
The clinker is likely too hot. The Bixcheck software should be used to reduce the Ash Dump Heat level. Default is 4, but might need to be 3 or less. This is explained as follows by Tomorokoshi in the following thread http://forum.iburncorn.com/viewtopic.php?p=78447 "Are your clinkers elliptically shaped? If they are, then they are still too hot when the ash dump process happens, and they are deforming so that some material is getting hoisted up where it should not be. When the clinker is compressed, it gets taller. The relatively cold paddles then flash-freeze the clinker material to everything. This can lead to jamming problems. ".
Dump cycle runs but produces no clinker:
From Tomorokoshi http://forum.iburncorn.com/viewtopic.php?t=5158&postdays=0&postorder=asc&start=15: "It is possible for the ash dump cycle to run without dropping the clinker. There are a couple possible ways for this to happen: 1) The clinker is too small and sticks to the side. The push out tab does not reach the clinker. 2) The paddle drive adjustment is out of tune, which makes the paddles not clear the burn pot all the way. This holds the clinker in at the leading edge. 3) You are on the wood pellet setting (unlikely). After you start up the stove and it has run for a while, empty out the ash drawer completely. If the ash dump cycle runs but it does not drop the clinker, there should still be some ash and dust that gets into the drawer. Alternatively, you can run a piece of tape between the drive cam lever on the drive motor and the bracket. If the motor runs, the tape will get torn. Another way, if you had the software, is to data log the stove operation to a file and then graph the file to see if it went through that process. Are you able to see the transition between the two clinkers? If the ash dump process never happened, there would be no transition. If the ash dump cycle happened, there should be a demarcation between the clinkers.
Dump cycle doesn't complete. No clinker. Subsequent Overflow.
From Ileed http://forum.iburncorn.com/viewtopic.php?t=5527&highlight=file: "I think you will find that the stove started a dump, and the bottom paddle is hung up on the bottom of the burn pot, jammed, and shut down. You will smooth the edge of the bottom paddle, put a bevel on it. You can probably do it in the stove, but I removed mine. To remove, take out the upper floor, burn pot, and upper paddle, then, remove the lower front grill, and pull the igniters back, and lift out the igniter holder. Now you can remove the lower paddle. Take a file and smooth the inner edge, or but a bevel on on. I would smooth the bottom, outside edge, of the burn pot. Put it all together, and it should make a dump at 20 hours, without jamming, and shut down."
From Rustydog http://forum.iburncorn.com/viewtopic.php?t=5787&start=15 :"My stove was manufactured in 2006 . Mine had a defect in the fire pot, it was cut incorrectly where the cutter slides through the fire pot slot and would jam all the time. I drove over to my dealer and looked at other Maxfires on the show room floor and it was obvious right away by comparing it with mine. My dealer exchanged it on the spot and the problem has never returned."
From JET http://forum.iburncorn.com/viewtopic.php?t=5787&start=15: You should file the sides of the slot, like so. (Click on the thumbnail at right)
From Tomorokoshi http://forum.iburncorn.com/viewtopic.php?t=6721&start=10: "The first thing to look at is the general shape of the clinker that you get - for this part, of course it's best to have one that actually drops out. Anyway, the clinker should be "perfectly" round - you should not have any hint of an oval or elliptical shape. If there is (see above re. elliptical clinker). The second thing to look at is if the clinker is too small. If the clinker is, suppose, 55% of the proper size, it might not actually fall out because it is held in a little and the ramp on the upper paddle didn't kick it out. You then wind up with a "double" clinker that may exceed the ability of the stove to drop it. The third thing, which is mechanical in nature, is what is known as the "ash dump timing adjustment" or something like that. Notice on the burn drive motor cam ball joint push rod linkage that there is a turnbuckle to set the length of the push rod. If the paddles do not sweep far enough over, the edge of the clinker on the right side of the stove will ever-so-slightly be held up by the rim of the opening of the lower paddle. The proper adjustment for the push rod is to run the motor IN THE FORWARD DIRECTION ONLY (due to backlash reasons) until the cam and the push rod are in line. This is the maximum opening point of the paddles. Now, adjust the turnbuckle until the clearance between the paddle opening and the lower rim of the burn pot is at least 1/8 inch. Watch out for the paddles bottoming out on the back of the firebox."
Bobbr1 phrases Tomorokoshi's #3 item above as follows http://forum.iburncorn.com/viewtopic.php?p=89919: "Open the stove as you would for a cleaning, remove the burn pot and with the power off release the brake (push in on the little black strip down towards the bottom of the gear motor .. control board side) on the gear motor and manually cycle the paddles to the open position (Do this in a clockwise motion) with the hole completely open to the ashpan, check to see that the top paddle completely clears the back side of the hole. If it doesn't clear, the cookie will hang and not drop causing jams etc. To fix, remove the shoulder bolt holding the tie rod end to the arm on the gearmotor .. loosen the jam nut and turn the tie rod end in a turn or two, replace the shoulderbolt and check the result. Keep adjusting it until the trailing side of the paddle clears the hole ... "
Dump cycle fails with loud buzzing:
From JET http://forum.iburncorn.com/viewtopic.php?p=70509 : "The [brake] is sticking on your burn drive motor. That piece that you have to press in, is the metal piece on the end loose? It is the part that should be sucked into the motor. If that is loose, a new pop rivet will fix it. If it isn't, then the brake mechanism on the bottom of the motor is sticking. If you want to mess with it, it is very easy to take off. I believe there are instructions on here already. If you don't want to mess with it, then it should be covered under warranty and you can contact your dealer." See Dumps but Paddle Doesn't Return to Correct Position for details on dissassembly and repair of the burndrive motor. See http://forum.iburncorn.com/viewtopic.php?p=122214 for a video of a buzzing burndrive motor and the procedure followed to diagnose and fix the problem.
Dumps but paddle doesn't return to correct position
From Blume98 in the following thread http://forum.iburncorn.com/viewtopic.php?p=78424 : "Sounds like [brake] on motor not coming on,it should be in out position,this should come on when arm hits switch, also make sure switch is close enough to arm to trip it ,may need a little adjustment."
From CornCanuck in the same thread : "Also check that the switch itself is not loose. Mine came loose last week and I was seeing jams and I couldn't figure out why. The 2 screws were loose on top and even the nut fell off on 1 of them. Just tighten them back up if that is the case: easy to do."
From LET in the same thread: "The brake is the plastic & metal lever that is on the bottom edge of the motor on the (left) side toward the back of the stove. When the motor is pulling current it creates a magnetic field that holds the metal tab on the brake in to release it, when the arm hits the switch it cuts the power to the motor and the brake should release. Something on yours is causing it to stick so the motor doesn't stop and just coasts to a stop. If you lube it make sure the lube is safe for plastic or it will kill it." In the particular incident, the brake was indeed sticking and dry teflon lube was used to free it. Mary B and others, however, caution against using any lube. It eventually clumps and causes more problems than its worth.
Shown are the underside of the Maxfire burndrive motor. The upper bearing assembly is removed to show the brake in the "braked" position (left) and stuck in the "unbraked" position (2nd from left). The two right composite images show all the components for two different types of drive motor (Rex and SPG). These mosaics are taken from Quark's Corner http://www.scribd.com/doc/11795096/MaxFire-Burn-Drive-Motor. Click on the thumbnails for a larger view. See http://forum.iburncorn.com/viewtopic.php?p=122214 for more photos of the burn drive brake mechanism plus a discusion on how the stuck brake in the 2nd photo was fixed. In the particular case, one of the pivoting plastic parts (called Short Locking Arm, or pawl) was sticking on its bushing. A 23/64" drill bit was used to ream out the tight part, and the motor was as good as new. Other issues to consider: 1) The brake lever arm could have become magnetized. Test by seeing if a staple or small washer will stick to it. If so, replace the lever arm. 2) The motor winding could have become weak. It's resistance should be in the order of 2.5 Ohm. If much less, some windings are shorted. In this case, the motor would need replacing. 3) The brake lever arm could be bent. If so, bend it back into shape, maintaining a matching curve around the corner of the motor.
From Quark ( http://forum.iburncorn.com/viewtopic.php?p=103998 ): "I would look at the burn drive limit switch. Two things stop the burn drive motor. 1) The limit switch at the end of the burn drive cycle. The switch does two things - first it drops the power to the burn drive motor and second it tells the stove if the motor stopped in the correct position. 2) The motor is also stopped by a timing circuit which when timed out could position the motor about where you say it is stopping. So if the limit switch is not seen, the motor will time out. ... The burn drive motor takes about 10 seconds for it to make one revolution ( 6 rpm). Time it and watch the action of the motor with the side panel off. Does it make 3/4 of a revolution or 1 3/4 revolutions? If it's 1 3/4, then it is missing the limit switch. There are a couple ways to adjust it: with the screws holding it in, or by bending the tab. If it did not work at all you would get a #7 at startup when it does the 3 turns to empty it out. If it is moving slowly and it times out, then maybe something is getting stuck in there. Do you ever hear a stuck buzzing sound?"
Dump Cycle Doesn't Start
If one or both of your igniters is burned, and you have version 2.02 or earlier software, then the ash dump will not occur. Upgrade your software to ver. 2.06 or 2.71 and/or fix your igniter(s).
Burn Drive Motor Limit Switch
The limit switch is snap-action switch that stops the burn drive motor at the end of an ash dumping cycle by cutting the power to the burn drive motor. It also tells the stove if the motor stopped in the correct position.
The switch is available from Bixby but is probably not worth the price of shipping. In a pinch it may be obtained inexpensively from electronic component stores. Dolan remarks that it is used as a neutral switch on the shifter of 200 series John Deere lawn tractors. Jrbeane67 found one on Ebay for $2. See http://forum.iburncorn.com/viewtopic.php?p=121557 for other suppliers.
To adjust the limit switch, see Dumps but paddle doesn't return to the correct position.
For the Bixby procedure for replacing the burn drive limit switch, click on the 2 thumbnails at left, or download the procedure from http://www.scribd.com/doc/3349883/Replacing-the-Burn-Drive-Motor-Switch-115, courtesy of Quark.
Removal of Lower Burn Pot
The [lower burn pot] can be removed after the ignitors are pulled out of it. From JET http://forum.iburncorn.com/viewtopic.php?t=5787&start=50 : "The igniters are not spring loaded, there is a metal clip holding each one in. To move them out you can stick a screwdriver in the louvers to move the clip to the side, then slide the igniter out as far as it will go. That should give you enough room to get the lower burn pot out. Then when you slide the igniters back in, the clips will pop into place and hold them in. Be careful if you have the ceramic igniters, they are brittle."
Bellows on Ash Dump Arm
The rubber bellows is not intended to be a user-serviceable item. There have been very few reports of the rubber breaking. When it does, it may be replaced under the Bixby 4/7 year warranty. Den ( http://forum.iburncorn.com/viewtopic.php?t=8645 ), however, managed to fix his broken bellows by trimming back the broken end and reattaching it.
Bixby Guides re. Ash Dumping
Bixby Guide on Repairing a Non-functioning Brake: http://www.scribd.com/doc/3153160/Burn-Drive-Motor-Brake
Bixby Guide to Troubleshooting Burn Drive Motor: http://www.scribd.com/doc/3155811/Burn-Drive-Motor-Does-Not-Operate
Bixby Guide to Troubleshooting Burndrive Motor that doesn't Park: http://www.scribd.com/doc/3155814/Burn-Drive-Motor-Does-Not-Park
Bixby Guide to Replacing Burn Drive Motor - Model 115: http://www.scribd.com/doc/3349886/Replacing-the-Burn-Drive-Motor-MaxFire
Thermocouple
The flue thermocouple connects to J18 of the motherboard of a model 115. According to idpomfret, the left wire is red, and the right wire is yellow. He found that he had somehow installed it upside-down even though the factory connector is (usually?) keyed.
Additional details on the thermocouple are available in the Electrical Components section of the Bixby main page.
Testing the flue thermocouple
Continuity check: Disconnect the thermocouple at the motherboard. Test its resistance using any of the lower resistance scales of a multimeter. The reading should be near zero. If not, you have a broken wire or a disconnected or loose junction. Replace the thermocouple. In a pinch, if the junction is loose or open, you can remake it simply by cutting off the tip, stripping off a 1/2" or so of the 2 wires, then twisting the bare ends together tightly using pliers. In the long term, it should be replaced with a properly welded junction.
Functional Check: With the thermocouple connected to J18 at the motherboard, and with the door closed and the stove cold, off, but powered, heat the pipe (that connects the exhaust mainfold to the exhaust fan) using a propane torch or possibly a hair dryer or heat gun. Be careful not to damage the wire itself by overheating or scorching it. If the thermocouple is working, then the stove should detect a heat rise and the convection fan should start. Quark's variation of this test is to remove the wire from the flue then heat the tip using a lighter. Note that you cannot test the thermocouple by directly measuring voltage with a multimeter. That would introduce 2 new thermocouple junctions in your thermoelectric circuit at your multimeter probes.
Replacing the flue thermocouple
Instructions are courtesy of Quark's Corner. Click on the images to enlarge them. http://www.scribd.com/doc/3349989/Replacing-the-Thermocouple-115
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Gaskets
Burnplate gasket
From BarabooBurn http://forum.iburncorn.com/viewtopic.php?p=90490 : "The gasket is easily replaced...$5.99 (includes sealer) at Menards. Remember to use the flat 5/8 gasket. And only put the sealer in a few locations to hold the gasket in place; otherwise you will be scraping madly when you want to replace it again!"
Bixby procedure for replacing the burnplate gasket of the model 110 (more complicated than for the 115 and later): http://www.scribd.com/doc/7492046/Replacing-the-Top-Burn-Plate-GasketMaxFire-110
Door gasket
Warning: for the MaxFire, you are not going to like this. According to the factory, the door gasket is special and it requires special installation. At time of writing (early 2009), the factory does not permit dealers to replace them. It is a safety feature and must be installed correctly by the factory. To replace the gasket, the factory requires that you ship to them your door! The cost was reported to be in the order of $100 plus shipping both ways http://forum.iburncorn.com/viewtopic.php?t=9939. As explained by JET in the same thread: "Yes, the door gasket must be replaced at Bixby and it is a real (pain to replace). The gasket is siliconed in with some very expensive stuff since it gets so hot and the gasket isn't real cheap, then you have figure a good hour of labor at least." International or anxious customers might consider enquiring about the cost of a new door. Moral: be gentle to your door gasket. Do not run anything abrasive over it. Do not overtighten the door latch. Inspect it carefully at the end of the heating season so that any needed replacement could be done at your convenience. Then take a sedative.
There is one bright light. According to Blume98, if the gasket damage is minor, it can be fixed with a minimal amount of red RTV silicone to glue down the frayed strands. You could temporarily insert a piece of aluminum foil between the gasket and the door to prevent the wet silicone from sealing the door.
For the UBB, the news is better. Bixby will sell the user a door gasket with a warning that it must be installed correctly or the window might break. It has to be torqued in. Ref.: http://forum.iburncorn.com/viewtopic.php?t=10087.
Air Pump and Igniters
To test the air pump, [Quark advises]: "...just pull the hose off of the Air Pump, start the stove until the Air Pump comes on and feel if air is coming out. DO NOT let it run for any length of time - to protect the igniter. IF your problem is that you don't seem to have enough air going through the igniter, check on the igniter for a small screw. Not sure if it was on all of the igniters, but it acts as a control valve. It was installed so if the Air Pump started to get weak, you could back the screw out maybe a half turn to allow less restriction and more air to pass." First, check the air filter on the air pump. Clean it if necessary.
Bixby Guide to Troubleshooting Air Pump: http://www.scribd.com/doc/3155809/Air-Pump-Does-Not-Operate
Bixby Technical Support Bulletin on 110/115 Igniter Burnout: http://www.scribd.com/doc/3153055/TSB002-115-110-Igniter-Burn-Out
Version 2.02 software doesn't allow an ash dump if an igniter is out. This is corrected with software ver. 2.06. See TSB-003: http://www.scribd.com/doc/3248778/TSB003-Software-2-06-Release.
On the MaxFire (S/N 3000 – 9800) NOTE: An igniter board (also called daughter board) may get damaged when an igniter burns out leaving the igniter circuit in the "ON" condition. When this happens, the fuse may likely be damaged as well. When an igniter is burned out, do the following test to assure proper solution to the problem: 1) Unplug the stove. 2) Replace the slow blow 6.3A fuses (on the Daughter Board) with a fast blow 5 A, 125 V. DO NOT use the original 6.3A slowblow fuses. According to Tomorokoshi http://forum.iburncorn.com/viewtopic.php?t=10113, they didn't react fast enough to prevent damage to the ignitor board. Some sources of the fuse are listed in the same thread. 3) Unplug the damaged igniter. 4) Unplug the exhaust fan, (J13 on the main control board), plugging it into an igniter port (J5 or J7) on the igniter board. 5) Plug in the stove. If the exhaust fan runs, STOP - the igniter board is bad - Replace the igniter board. Test the other igniter port in the same manner. If the exhaust fan runs while plugged into either igniter port, replace the igniter board. NOTE: If an igniter is burned out on the stove, the stove may not perform the ash dump.
For the Bixby procedure for replacing the igniter board, click on the thumbnail at right. Courtesy of Quark's Corner http://www.scribd.com/doc/3349970/Replacing-the-Igniter-Board .
From Blume98 on the subject of frequent igniter burnout http://forum.iburncorn.com/viewtopic.php?p=144219: "There was a problem with some (igniter) boards. We replace them under warranty a lot of time. There are a couple of resisters (R16 & R18) that were soldered too close to board causing the tryads to come on without air pump."
Blume98 also says http://forum.iburncorn.com/viewtopic.php?p=151991 : "Another thing to look for on air pump, there is a very small hole under filter, that is where it gets air, if plugged or restricted it could cause igniter to burn out, there are a few different type of air pumps i think earlier pumps are the ones with small hole, not positive as i don't have one in stock to check, just something to check before it gets cold."
Frequently blowing igniter fuses? See this multipage thread: http://forum.iburncorn.com/viewtopic.php?t=10397. The resistance of igniters varies somewhat from one to the other and with their temperature. Considering that Voltage (V) = Current (I) x Resistance (R), a 25 Ohm igniter could blow a 5 Ampere fuse with a surged voltage of only 125 V (i.e., 125 = 5 x 25).
Testing Igniters From Quark http://forum.iburncorn.com/viewtopic.php?t=12126: "Turn stove on, wait about 15 seconds after the air pumps turns on, open glass door, push safety switch in, (grab the deflector and using it as a handle) lift front edge of upper burn plate and look down at the igniters. Glow is good, no glow is bad - check fuse, if fuse is good, igniter is bad."
Replacing the MaxFire igniter(s): Unplug the stove. Remove the left and / or right side screws and panel(s). Using a 5/64" hex head wrench or a Philips screw driver, remove the screws holding the lower louver in place. Remove the louver. Clip the cable ties holding the Igniter wires. Mark the igniter wires “upper” for (J5) and “lower” for (J7) so you don’t mix them up. Unplug the igniters from the main control board.
NOTE: READ BEFORE CONTINUING If an error code of (#7 & #1), (#7 & #2) or (#7 & #1-2) has occurred, follow the next instructions BEFORE REMOVING either of the igniters! DO NOT ASSUME!
Using an ohmmeter (use the lowest scale), measure the resistance of each Igniter to determine which Igniter is BAD. A good Igniter will read +/- 28 ohms. Once it is determined which Igniter is bad, continue with the following instructions.
Remove the grommet. With one finger, move the securing clip out of the way. Using needle nose pliers (any other tool or a wire with a hook on it) to pull the igniter out about 2" past the front of the stove. Remove the air hose from the igniter. Remove the igniter ground wire from the igniter. Do not disconnect the ground wire at the stove. Blume98 and Rona warn us that it is difficult to reconnect at the stove. Pull the igniter the rest of the way out. Feed the new igniter plug & wires through the grommet hole. Insert the new igniter into the hole in the side of the firebox. Attach the ground wire and air hose to the igniter. Push the igniter back into the lower burn pot into the igniter tip guide. Make sure the securing clip has moved over to hold the igniter in place. Plug both igniters back into the main control board. Replace the rubber grommet. Secure wires with cable ties. Put the lower louver back on. Install the screws. Plug the stove in. Check for proper operation. Install the left and / or the right side panel(s) and screw(s).
Be careful if you have the ceramic igniters, they are brittle.
Loud Igniter? No, you're not nuts. According to Enerjet: "Yes I had an igniter get loud. The ceramic cement that seals the hole where the wires go in the the igniter blew out. This appears to cause insufficient airflow over the igniter and it will eventually fail." Click on the thumbnail at right to see Enerjet's loud igniter with blown seal. According to FreshSqueeze, an igniter will also go loud to its imminent demise if its air tube disconnects.
Converter Box
The converter box is a galvanized junction between the vent pipe and the stove. It's role is to separate the intake air from the exhaust. It is accessible from inside the right side panel of the stove (when facing the stove). It is not designed to withstand the corrosive cocktail of corn soot and water. To prevent it from corroding prematurely, ensure that all inner and outer vent joints are sealed. Install outside horizontal vent pipes on a slight downward slope outwards to expel any condensation and penetrated water.
According to Fireblade : "Upper convection box screw on the right side is a huge pain in the butt to remove. I broke it loose with a 1/4 drive with 5/16 socket. I then drilled holes in the handle of a 5/16 nut driver, put it on the screw and proceeded to turn the nut driver with a small Phillips screw driver inserted into the holes that I drilled through the handle for leverage. "
Bixby Guide to Replacing Converter Box - Model 110: http://www.scribd.com/doc/3349904/Replacing-the-Converter-Box-110
Bixby Guide to Replacing Converter Box - Model 115: http://www.scribd.com/doc/3349908/Replacing-the-Converter-Box-115
Heat Exchanger Tubes
From JET http://forum.iburncorn.com/viewtopic.php?p=123780: "There are several things that play (for stove longevity) and yes it is the heat exchanger tubes (aka convection tubes) that will (likely) kill the stove. Some corn seems much more corrosive than other corn. Higher heat levels seem to be better. Proper storage for the summer is KEY to a long stove life. With good care I would say it is going to be right around 7 years +/- 2 years. With that said, it is feasible for a handy person to replace the tubes on a 115. The stove is totally put together with rivets, so you could pull the firebox off and put new tubes in it, they would need to be welded on both ends for a good seal. It wouldn't be easy, but if the rest of the stove is in good shape, it may be worth it. Burning wood pellets gets rid of most of the corrosion issues. ... The tubes are readily available, they are just aluminized mild steel DOM tubing. The only other material I would consider is AL29-4C, like in the newer Bixby pipe. The heat transfer likely won't be as good as the mild steel, but it might last longer."
[ Tips for cleaning the heat exchanger ]
Carbon Monoxide Detected
The Bixby stoves are amongst the safest by design. Contrary to most stoves, they have no augers which can act as a direct path of fumes from the firepot to the room through the fuel hopper. Instead, the stoves feature a ferris wheel and a feed wheel gasket which seals between the hopper and the firepot. Nevertheless, rare sequences of events can cause CO to leak into the room. For this reason, carbon monoxide (CO) monitors and alarms should be installed in all rooms having combustion devices, including a Bixby stove.
As explained by Tomorokoshi http://forum.iburncorn.com/viewtopic.php?p=122515 to a user with a CO leak and a nonstandard vent configuration: "The CO leak is a result of a number of issues all sequenced together.
1) Something make the stove overfill. This is the initial trigger to the problem. Let's try to track this down. 1.1) Did the temperature change drastically recently? 1.2) Were the trim pot knobs adjusted recently - particularly to make it run richer? 1.3) Did the fuel change? New supply? 1.4) Even without those above, other things could happen.
2) The fuel overfill made the stove shut down. 2.1) The fuel filling up blocked new fuel from getting in, making the fire go out. 2.2) The fuel in the tube could have make the feed wheel get stuck - not sure at this point.
3) The fire going out triggers the shutdown process. 3.1) The overfilled fuel does not burn well, and does not produce enough heat for the stove to consider itself to be operating properly. 3.2) Even though there is a lot of fuel, because it is not in the burn pot it will not burn well - but it will still burn.
4) The CO is coming from the smoldering fuel left in the stove after shut down. 4.1) The exhaust fan will run for a time after the low temperature is detected. This is to clear out the remaining fuel for a normal shutdown - for an overfill, there may still be burning fuel in the machine.
5) With the exhaust fan off the CO can get into the house. 5.1) The feed wheel tube, ash drawer, and fire door are fairly well sealed, but not perfectly sealed. 5.2) A negative pressure in the house - due to gas appliances or fans, can draw some air through the stove and into the house.
6) There are a number of shutdown modes that could have happened. 6.1) Low operating temperature - #2 light; 6.2) Blocked feed wheel - #8 light; 6.3) Blocked flue shutdown - #2, #3 lights
If we can fill in some of the details we can narrow in on what happened. If the stove is at 2.02 or 2.06 (version of firmware), then an update to 2.71 (using Bixcheck software) will deal with some of those issues, as the shutdown processes were modified."
Incorrect exhaust fan settings (e.g., a zero ashdump fan setting) in the calibration fuel tables can also contribute to smoke in the room, as reported by Logger in a situation aggravated by a worn feedwheel gasket.
Miscellaneous Problems
Stove Doesn't Respond (Locked Up)
Click on the graphic for a troubleshooting procedure to follow in the rare event that a Bixby stove doesn't respond.
For a higher quality image, download the following Bixby Troubleshooting Guide: http://www.scribd.com/doc/3155821/Stove-Does-Not-Respond
Motherboard failed? This is rare. If yours failed, you could have an electrical problem in your home. Use a circuit tester to check the circuit that your stove is plugged into. Correct any problems including broken ground. Use an AM radio on the same circuit and listen for static that might be correlated with other nonlinear loads on that circuit. They may need to be isolated electrically from your stove. As Blume98 experienced ( http://forum.iburncorn.com/viewtopic.php?t=9580 ), something as simple as the arcing from a faulty switch on another device on the circuit can contaminate that circuit with enough harmonics to cause other electronic devices (including your Bixby's motherboard) to malfunction. Powering your stove through a good surge protector (with filtering) can help, but it is better to fix or remove the offending devices on the circuit . See http://forum.iburncorn.com/viewtopic.php?p=112907 .
Bizarre behaviour (e.g., turns on when it shouldn't) You could have an electrical problem in your home. See the advice above under "Motherboard Failed?" After correcting any electrical problems, try to reset the stove parameters to default; i.e., recalibrate. If that doesn't work, try reloading the stove firmware then recalibrating.
Stove collects corn/pellet dust in cabinet and/or blows it into the room
From COman ( http://forum.iburncorn.com/viewtopic.php?p=99160 ): "...I removed the feed wheel and found that underneath the wheel was packed with pellet dust. I cleaned under the feed wheel and reassembled it have had very little trouble since."
[Blume98 recommends] placing a spongy seal under the feed wheel and over the shaft. Teosinte uses a scrap of fibreglass furnace filter as shown in pixture at right. In the same thread, Oldschool suggests to "check for any spots on the underside of the hopper where silicon sealant is used. See if a spot was missed during manufacture or has come loose."
Plugged feeder drop tube? The dust in excessively dusty fuel can ignite in the drop tube when operating at high temperature. This can leave deposits or "speedbumps" inside the tube that can eventually lead to plugging as discovered by BagOFur. To prevent this, clean your fuel before loading it into your stove. Also, routinely clean the "speedbumps," by simply soaking the the drop tube in water as shown above under Maintenance tips.
LED lights not working correctly?
If the LED lights are not working correctly, suspect the touchpad or its ribbon cable and connector. Click on the 4 thumbnails for detailed illustrated procedure for replacing the touchpad of a Maxfire stove, courtesy of Quark's Corner: http://www.scribd.com/doc/3349992/Replacing-the-Touchpad-MaxFire .
External thermostat & AutoStart on/off
Click on the graphic to see factory instructions for installation and operation of an optional external thermostat.
Tomorokoshi (http://forum.iburncorn.com/viewtopic.php?p=135163) advises that thermostat placement can be critical. If too far from the stove's "reach," then the room with the stove will get very warm. If the thermostat is too close to the stove, then other parts of the house might get cold. Extra circulators, air flow, and insulation make thermostat positioning a tricky thing. Consider using a wireless thermostat. These come in two parts and use radio. The thermostat part is like a remote control that can be placed somewhere. You can experiment with different locations in the house to find a suitable location.
Jawquin ( http://forum.iburncorn.com/viewtopic.php?p=97249 ) advises that Auto start on/off is fully functional with the latest stove firmware and BixCheck 2.71 software as of 2008-03-15. To invoke the feature, use Bixcheck to change the fuel table setting "Thermostat heat level" to 0 (i.e., zero). This is especially useful during the shoulder seasons when outdoor temperatures are mild. In this mode, the stove will cycle on and off and go through the normal shutdown cycle as governed by the thermostat. During colder weather, set that level to 1 or higher depending on heat requirements. The stove will then cycle between that setting and what ever the higher setting is set at, without shutting off. A programmable thermostat should be set with a temperature differential of at least 2 or 3 degrees to prevent excessive startups at the expense of igniter life.
If your stove is connected to a thermostat, and if the thermostat is not calling for heat, all LED indicator lamps will flash (up to the present heat setting) to indicate this condition. This occurs whether or not the AutoStart setting is activated.
BixCheck Software
Background
BixCheck is the optional software interface to the Bixby stove that you can [download for free] from Bixby. It allows you to monitor operation, adjust calibration, and test stove functions via a serial connection to your computer. Parameters can be changed while the stove is running, and because they take effect immediately, the stove can be adjusted for best performance to compensate for changes in fuel, venting, altitude, or other parameters that will naturally be different from those in which the stove was developed and tested. The production version of Bixcheck comes with detailed instructions for its operation.
Your BixCheck software has no instructions? No problem. You downloaded a test version of BixCheck. For detailed instructions, download the latest production version of Bixcheck. Alternatively, you can use the HELP button in BixCheck to obtain information and examples on almost any functionality of the software. To use it, click on the HELP button then click on the input button or output field of interest in any open BixCheck window. The following information is provided to supplement rather than repeat this information. Consult the Bixby instructions for detail.
Warning The software was first developed for the needs of trained service technicians. It is a very powerful tool but it can damage your stove or affect your burn if used inappropriately. If you aren't sure what you are doing, DON'T MESS WITH IT. See [example] of what can happen when a user inadvertently sets a key parameter out of range.
Bixcheck Software Notes and Version History
Click on the 3 thumbnails for release notes on the 3 latest versions of Bixcheck software. Version 2.06 is the latest official release and it is the version provided in new stoves sold by Bixby (this information is current as of December 2009). Versions 2.70 and 2.71 are test versions that work so well that most members of http://forum.iburncorn.com use version 2.71 as the de facto standard. For full details on these and earlier releases, see Quark's Corner at http://www.scribd.com/doc/3250258/BixCheck-Software-Notes-and-Version-History
Can I upgrade from a much earlier version of software?
From http://forum.iburncorn.com/viewtopic.php?p=114100 : It is possible to upgrade directly to stove firmware 2.71, for example, without upgrading through intermediate versions. The exception would be when upgrading from a very early version of stove firmware. According to Tomorokoshi regarding a stove (s/n in the low 3000 range) with version 1.22 that wouldn't upgrade: "It is possible that there is no bootloader in that stove... If that's the case, the board will need to be replaced. Any Model 110 / 115 board will do from Bixby because they will (now) all have the bootloader in it."
Compatable with Vista and Windows 7 ?
Bixcheck 2.71 is compatable with all Windows operating systems including XP, Vista, and W7.
Where can I download Bixcheck from?
Bixcheck software may be downloaded from: http://bixbyenergy.com/stoves/downloads
Cable
Bixcheck uses a custom TTL to serial cable for interface with your computer. It is available from Bixby dealers. The location of the connection port for the cable is described as follows by LET http://forum.iburncorn.com/viewtopic.php?t=5814&highlight=cable: "The port is on the upper left corner of the main board, it is black, the lock on the connector goes toward the inside of the stove. When you remove the connector don't forget to unlock it while pulling it out. Look right behind the trim pot board and you will see the connector." Pic of motherboard showing computer port (J3) . Technically, the cable may be connected and disconnected while the stove is running. For safety reasons, however, it is advisable to always turn the stove off while reaching inside near exposed electrical terminals.
The Bixby cable is designed to connect to a 9-pin DB-9 RS232 serial port at your computer. If your computer doesn't have such a port, you will need a 9-pin serial - to - USB adapter. The model ES-U-1001-A adapter available from http://www.easysync-ltd.com/ works well with the Bixby stove for this purpose. Rona reported that "Zonet USB to RS232 Serial Cable also works . Cost about $20 and bought from local Computershop". Mary B remarked that successful adapters tend to use the FTDI chipset for the bilateral TTL/RS232 conversions. There's at least one report of poor success with Belkin and Radio Shack adapters in particular. See http://forum.iburncorn.com/viewtopic.php?p=118435 for reviews of other adapters. You cannot use a null-modem cable. Avoid UPS power supply cables; they appear the same but are wired differently and will not work.
Note that most USB to serial adapters require 2 drivers: one for the USB hub and a second for the virtual com port driver. If you cannot communicate to your stove through a USB to serial adapter, suspect that one or the other driver didn't install. To see and set your com port drivers from Windows XP: right Click on My Computer --> Properties --> Hardware --> Device Manager --> COM Ports .
Cable pinout at Motherboard J3, from the top down as you are looking at it in the stove, courtesy of Mary B( http://forum.iburncorn.com/viewtopic.php?p=99466 ): pin 4: Ground, yellow ; pin 3: +5 volts red ; pin 2: RX black ; pin 1: TX green.
COM port settings: 9600 baud, no parity, 1 stop bit.
Loading the Stove Software (Firmware) Using Bixcheck
From LET http://forum.iburncorn.com/viewtopic.php?p=90038: "The best way to get the software to load is to unplug the stove (ac power), then open bixcheck, go to the download menu, choose internal file, click send and plug the stove in. I have found that if I read back the current software and then to the load menu it won't always start loading, if I do it the above way it works every time."
If you upgrade the stove firmware, then you must recalibrate the stove . From Tomorokoshi http://forum.iburncorn.com/viewtopic.php?p=113440 in response to poor stove performance after a firmware upgrade: "This is exactly what happens when the software is updated without doing a recalibrate. The data format of the fuel tables changed over time as more parameters were added, resulting in the data showing up in the wrong place. However, if either the data format mismatches or the checksums don't match, then the stove will not use the adjustments and use the default internal tables. This provides some amount of operation, although it won't be optimal."
See also the thread at http://forum.iburncorn.com/viewtopic.php?t=6417.
Tomorokoshi advises as follows in cases when the computer crashes during a software upload, and then the stove no longer functions: "...The downloader connected. It got as far as erasing part of the old program. The stove is stuck in reset because the program is corrupted when the computer crashed. However, there is a second problem: the blue screen. Are you using a USB to RS-232 adapter? Which model are you using? Can you tell which drivers are installed? When we (Bixby) first started using the adapters, the drivers of some models would crash the system straight to a blue screen. If you can track down anything with the adapter, then it's possible to attempt the reprogramming again. The bootloader is still there, and it will reprogram the stove - there just isn't any main program in it."
Stove Recalibration
Before you update, run the Monitor, do a Readback, then write down the Manufacturing date. When you update the software it will overwritten with the present date and you will want to change it back to the original date after the software is installed. This is not required, but nice to have for future reference.
How to recalibrate the stove (courtesy of Farm Boy http://forum.iburncorn.com/viewtopic.php?t=6417):
1) Select "Monitor 5.0". 2) In the middle of the Monitor screen, select and arrange the "Fuel A Data", "Fuel B Data", and "Telemetry" windows. 3) Select "Readback" to get the current data from the stove. If the stove had older software before being reprogrammed, some data will not look quite right. That is fine at this point. 4) You should be seeing information in the "Data In" window, as well as action in the "Telemetry" window. If not, diagnose any connection problems. 5) Select the model you have in the upper right; either "Bixby Model 115" or "Bixby Model 110". 6) ! Very Important !: Select the "Individualize", "Calculate Fuel A", and "Calculate Fuel B" buttons. The data in the fuel data windows will turn orange, along with a couple places on the Monitor screen. 7) Select the "Format" button. You will get a confirmation message; select "Yes". 8) As the data is sent to the stove, the boxes will turn from yellow to white. Make sure the data is what you expect after the boxes turned white. 9) You are now finished with the calibration process.
Bixcheck can't Communicate with your Stove?
See ibc thread #136367, which speaks of serial ports and of ensuring that the version of your stove's software is matched to your version of Bixcheck. When in doubt, upload new version of software to the stove using the internal file that is imbedded in the later versions of Bixcheck software that you can download from the Bixby site. Use that same version of Bixcheck to communicate with the stove.
If Bixcheck appears to hang up while you're Downloading or Calibrating, be warned that it can sometimes take 15 minutes or more while appearing stuck. According to Sandman, "patience is a virtue" in this context. Leave it alone for at least 15 minutes before killing any operations.
Lean Burn AutoRecovery
Vers 2.06 of the stove software includes a lean burn detection and recovery feature. When the flame is perceived to be perilously lean, the stove corrects for this automatically by increasing the feedrate temporarily. The #2 and 3 lights blink when this occurs. The detection feature exploits the history table that can be seen using Bixcheck. The stove enters lean burn recovery mode when the difference between the maximum and minimum values exceeds 25% of the "Drop limit" value in the Telemetry window (of Bixcheck) for at least 3 values. The values in the history table are the lowest sampled values of the thermocouple between the feeds. There is one entry per feed. This is the mechanism that is primarily used to determine the blocked flue shutdown case. For that, the range across the history table needs 2 samples beyond the drop limit value in Telemetry.
Update: The test version 2.70 of the Bixby software now provides adjustable sensitivity for the lean burn mode (i.e., the 25% criterion is adjustable).
Ratio / Ashdump Control Mode
Since test version 2.70 of the Bixby software, one can optionally give a MaxFire stove ashdump control by trimpot as with the UBB stove. In this mode, the Exhaust Fan trim pot will control the Lean/Rich ratio while the freed up fuel trim pot will control the ash dump rate. This mode is especially useful when burning unconventional fuels with exceptional or inhomogenous ash content.
To activate this mode, check the Ratio/Ash Trimpot box in the Fuel A and/or Fuel B tables in Bixcheck Monitor. To get an understanding of how it works, click on the thumbnail at right. While in Bixcheck, additional information is available by clicking the Help button in the Bixcheck Monitor window, then clicking on Ratio/Ash trimpot in the Fuel A or B table.
BixCheck Convection Fan Settings
The convection fan speed is governed by the flue (i.e., exhaust) thermocouple (TC) reading, to a max of 100%, by linear interpolation between 2 points that are adjustable from the BixCheck software. These points are the TC readings to drive the convection fan at 25% and at 100%, respectively. The following thread describes how BixCheck determines fanspeed from these 2 setpoints. Corny's example in that thread uses set points of TC 20 @ 25% fan and TC 130 @100% fan. The BixCheck defaults are TC 50 and TC 170. These defaults allow for a quieter fan (i.e., 68% of max fan speed rather than 93% at TC 120 which is a typical reading at heat level 4) at the expense of slightly less heating efficiency. http://forum.iburncorn.com/viewtopic.php?t=5369&start=6
How to Log Telemetry Data
Version 2.70 introduced the ability to log telemetry data into a comma-delimited text data file stored on your computer. You can then import this text file into Excel for analysis and graphing. This is invaluable when troubleshooting transiant problems, in particular. Click on the thumbnail for guidance on how to log your telemetry data.
How to Create Graph of BixCheck Log Data (Using Excel)
http://www.scribd.com/doc/3157044/How-to-Create-a-Graph-from-a-BixCheck-Log-Using-Microsoft-Excel
Bixcheck Diagnostic Tests
Bixcheck can carry out a suite of diagnostic tests on your stove and then issue you a report. To run the test, your stove should be plugged in, but off. Run Bixcheck, but instead of selecting "Monitor", select "Checkout" from the BixCheck startup window. The tests are guided on screen, with some automatic tests, and some interactive tests (you'll need to perform a requested task such as opening and closing the door during a test of the door switch). Just follow the prompts. At the end, you'll get a report.
Back to main Bixby Page
http://forum.iburncorn.com/wiki/index.php/BixbyFAQ
2010-09-9
