Considerations in installation
From Cornburning
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Please first read Placement within your home
Install information goes in this spot.
Vent Location
There are some handy videos for venting install on the Nesco Amaizablaze site: http://www.cornstoves.info/products.html
Thanks to Bixby for their NFPA Illustration
Outside Air Kit
Without air, there is no fire. Outside air kits (OAKs) introduce air into the firepot from the outside to support combustion. The alternative is for the stove to draw (already heated) air from the room which, in turn, is replaced by outside air drawn in an uncontrolled manner from whatever crack, crevasse or vent that the stove can find. Does a corn or pellet stove require an OAK? Opinions vary.
On the "Yes" side The arguments in favour are perhaps best summarized by Tallcorn as follows. "If your house is "tight" there won't be enough air in the room or house to replace the air the stove pumps out the exhaust.If you have a bathroom fan, kitchen exhaust or any other thing in the house that needs air, it will try to pull in back through your stove via the exhaust. If your house has leaks (and it does) wind blowing around it and over the roof will pull heated air out of the house and it causes a negative pressure in the house and in an attempt to equalize the pressure air is draw through the leaks and your stove's exhaust pipe. In some installations it is a "rule" or the law. That air in the house that is "enough" is air you paid to heat." In the same thread, Tallcorn goes on to say "I looked for other reasons why you should have the combustion air connected to the outside of the house. 1: Back burn into the hopper because of access to negative draft as the inside of the burn chamber is not in a closed envelope. An outside air connection completes a sealed loop. 2: Loss of electrical power stops the forced exhaust and natural draft takes over. Smoke will try to escape from the stove. The fresh air pipe if it isn't connected to the outside allows smoke to escape into the house. Test it. Turn off the power to the stove."
Another argument in favour of OAKs is that cold air loses its capacity to hold moisture when heated. Without an OAK, combustion air is drawn from the room, and its humidity is therefore decreased to a potentially uncomfortable level, making the occupants feel colder. Excessively dry air feels colder than air at optimum humidity levels. As Firepot Pete says in the same thread: "1. If you are getting any static shocks, then you need more humidity or more air circulating. 2. If your windows are sweating, then you need less humidity or more air circulation. Don't assume if you have sweating windows that you need less humidity in the house. Try moving the air for at least 24 hours before adding humidity. It takes a while to get the moisture back into all areas of the house and air. This is a problem with stoves like mine (6039), not a lot of air movement in side rooms without helping it a little."
The Bone noticed that his house stays warmer with his new OAK in the event that his fire goes out. With the OAK, his cold stove no longer exhausts warmed indoor air to the outdoors.
More from [ChimneySweepOnLine].
On the "No" side The following arguement against the general use of OAKs was found on Hearth.com. "Any combustion appliance requires a combustion air supply. The Outside Air Kit (OAK) enables a stove to pull air from outside of the house rather than from the room the stove is sitting in.
Unless you have a draft problem (difficult starts and backpuffing), an OAK probably will be of no value to you. Some argue that OAKs increase overall heating efficiency because the stove is no longer pulling cold outside air indirectly though the entire house but instead is pulling directly from the outside. However others would argue that home ventilation is actually very important, especially in modern tight houses, and that the effects of an applicance slowly replacing indoor air is actually quite beneficial. Also OAKs are generally uninsulated and often have intential gaps at the connection point to the stove – both of which can create a new source of heat loss in your home and possible cold drafts when the stove is not in use.
It is argued that an OAK prevents competition over combustion air between other fuel burning appliances in your house (furnaces, h/w heaters, gas dryers, etc.). They can also prevent problems when someone turns on an exhaust fan. If you have a nice tight house, an OAK could improve your stove’s operation. If you have draft problems that are helped by opening a window, you may benefit from an OAK. People with older “leaky” houses don’t usually have draft related problems, but some report that the house feels warmer because they aren’t having as much cold air infiltrating to replace what the stove uses.
Some have argued that OAK’s pose certain hazzards, such as flue reversals, under certain conditions (specifically when wind is blowing against the side of the house OPPOSITE the outside air connection creating a negative pressure zone at the air intake which could potentially cause a flue reversal). These issues are described on woodheat.org. See: The problem with outdoor air supplies: It seemed like such a good idea until it was tested
The OAK also requires occasional maintainance to keep it obstruction free. You also need to be careful to locate the OAK where it cannot get buried under snowfall, leaves, etc but also properly separated from the stove exhaust (or other exhaust) as reusing exhaust air would lower your efficiency.
As to how they connect, different models do it different ways, some go right into the combustion chamber, which keeps the pipe from leaking cold air in when the stove isn’t running, but means you are more vulnerable to clogs in the OAK pipe. Others just bring the air close to the regular intake, which makes the operation a bit less reliable, but allows you to still burn room air if the pipe gets clogged, however the pipe may allow more cold air to infiltrate the room when the stove isn’t running. It’s pretty much a question of how the stove maker feels like doing it.
In general, an OAK should be viewed as a solution to problems that have no other remedy. New stove installations should be designed to ensure the best possible draft without the use of an OAK. If you have a tight (probably tyvek wrapped), air-sealed house, you may need and benefit from using an OAK.
Finally it should be pointed out that an OAK is required by code in Mobile Home installs, and some or all other installs depending on your jurisdiction – check your local code."
