Combustion air intake, should I vent it from the outside or just let it pull from the room

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crouse77

New Member
Hearth Supporter
Jan 3, 2007
14
Des Moines, IA
I just put in a Breckwell Big E pellet stove and it pulls combustion air from the room. Does anyone know if it would be more effecient if I put in some pipe and vent it from the outside? Also what type of pipe would I need to use? There is not heat around it so I would think you could just use PVC, but code might suggest metal. Any information would be great. Thanks.
 
What does your manual say? What did the building/ mechanical inspector say when he did the inspection?
Thats the person to ask, after all he is the one signing his name?
 
The manual only says it needs to be vented to the outside when installed in a mobile home. It does say that you may need to open a window a little in a newer home that is relatively air tight. I don't think it says what kind of pipe to use for the air intake, I'll have to look again.
I haven't had it inspected yet, but I'm working on getting the permit. I know it's backwards, but I didn't know I needed one when I installed it.

I was just curious if anyone knew wether or not it would burn better with an outside air intake.
 
Not sure what you mean by "OAK". I'm sure that is going to seem like a stupid question when I find out what it is.

I bought it at a farm supply store. They didn't know much about installing them. My house is only about 15 years old and it seems to be insulated well, so it may be a good idea to pull outside air.
 
crouse77 said:
Not sure what you mean by "OAK". I'm sure that is going to seem like a stupid question when I find out what it is.

I bought it at a farm supply store. They didn't know much about installing them. My house is only about 15 years old and it seems to be insulated well, so it may be a good idea to pull outside air.
"OAK" Outside Air Kit.
Bob
 
It's been a debate here on and off. Old houses are not tight and may not need the OAK (outside air kit).
I do not have outside air.
My house was built in 1906. Been redoing it, new insulation, windows etc. Now the air is being drawn up from the basement which is leaky (fieldstone foundation) and between the basement and first floors are the registers and cold air returns (which are filled with insulation and blankets etc.) from the FHA system, and I can feel the cool air running along the floor (past my feet) and toward the stove. This is not so good.....
I am going to be installing outside air at the end of this season.
I have been on the fence as to whether or not to use OAK's for old house's but now I think they are a good thing, for newer houses I'd say a must.
Install the outside air.............. :)
 
your efficiency should be better with outside intake air, look at it this way, the air that is pulled through the stove is vented outside through the exhaust. now this air has to be replaced if pulled from inside the house,its going to leech in from outside, this will magnify any cold air leaks you may have in the home (around window sills, door seals etc.) by pulling outside air this will not happen, so you are not pulling cold air in, lastly , think of it this way as well, the air you are using to fuel the fire is the same air you are burning fuel to heat, and then ejecting it outside the home. so by pulling outside air,m the generated heat stays in the home, its flat out gotta be more efficient with outside intake air. we at englander require it on all of our models and even include the kit with the purchase. with it you do not have to worry about tight house negative pressure problems which can lead to a less than optimal burn, and you also save the heat that you have already paid to generate.
 
My state, WA, requires an OAK. It's my understanding that many counties will allow a varience if your home is old. I probably could have gotten a varience seeing as my home is older, and has many leaks, a few single pane windows, etc. But, I did not apply for a varience, mainly because I knew I would be remodeling this home and tightening it up quite a bit.

I installed the OAK and couldn't be happier with it. There's no pressure problem. No cold air being drawn into the home past leaks. Start up is a breeze, no window cracking. You will want to use all metal for the OAK. I used ridgid 3" galvanized pipe from the outside and elbows to get through the floor and to the stove. Then I have about a 10" piece of flexible aluminum connecting the pipe to the stove adapter piece. I also used a single sheet metal screw at each connection and aluminum furnace tape to seal up the intake real well. When there is a good fire going and the air all the way open you could suck a gopher through the OAK. I went outside and put my hand over the OAK and the pull of the stove is quite strong.


-Kevin
 
How much cold air comes in the house from the OAK when the stove isn't running but say the dryer or a bath fan is? Or when the wind is blowing hard on that side of the house?
 
shouldnt be any , the OAK is connected to the stove, the door to the unit will be closed, only way for pulled or blown air to get out is through the exhaust. as for the pull of negative pressure from a dryer or a bathroom vent, they dont run 24/7 like a pellet stove would. so the amount they could pull in is probably pretty similar (maybe even stronger with the dryer) ,but its only short term compared to a constant with a pellet stove. wind on the other hand, is somthing that only working on buttoning up the house itself is going to negate. and its going to do what it does in any situation. wood heat and insulation= maintaining comfort cheaper, they both are important factors.
 
Outside air kits also offer a concentrated place for cold air to enter the home (the OAK pipe and penetration) they also can make a stove work harder and burn less efficient because the stove has to bring freezing air to combustion temps, effectivy cooling the stove.
OHHH BOY here we go again. Scratch that. OAK is what you need. I dont have the strength for another OAK thread. :)
 
I got to find that thread where we ALL went round and round for about a month. If the book says to use it, then use it ;)

ahhh here it is...
https://www.hearth.com/econtent/index.php/forums/viewthread/2496/

I think i ended up somewere in the middle. Sometimes there necessary, and sometimes there not. its a intresting thread, manufactures have different opinions too. If you have time, its worth a read. I got realy educated on every aspect on outside air.
 
I read that whole thread, thanks for the input. It looks like it is a big debate. I'll wait to see what the inspector says and make my decision later. I may put on a teperary one and do some tests with and without it to see what works better. Thanks again.
 
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