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Nigel459

Feeling the Heat
Oct 24, 2017
342
Ontario, Canada
Hi all,

I'm considering a pellet stove in my basement for occasional use. It was recommended to me to do everything I can to avoid any backdraft/cold air ingress issues while the stove is not in use.

With an outside air kit, are all pellet stoves a sealed "closed loop"?

One dealer recently mentioned he thought that wasn't the case, and the OAK just put air in the back of the stove, not in a sealed loop fashion, i.e. cold air could seep out when the stove isn't in use. I think I read on here that there are only a few models that employ a truly closed loop, which agrees with that.

I'm wondering which stoves can be closed loops as well as any other considerations for a basement install.

Is cold air/backdrafting a usual problem? i.e. when the stove is not in use?

I have a wood stove on the main level with no OAK, in an open-concept, well-sealed 1300sf w loft and vaulted ceilings.

Thanks :)
 
Outside air is pulled thru the vent and stove only when the combustion blower is running. When the stove is off the outside air vent is a dead air space and not likely to leak any air into the living space unless you have the door open on the stove. I consider it a closed loop.
 
I was cleaning my PelPro 130 the other day and noted the OAK feeds the combustion chamber with no holes or vents to the room so like jackman said it looks like a closed loop...the only recirc air is room air in and then out after being warmed with the circulation blower.... fwiw...I notice when its cold (its been damn cold this year) the OAK pipe sweats a LOT since the outside air is -20 to -35c and chills the uninsulated pipe.... I had to put a metal plate (from COSTCO salmon/crab combo) under the pipe to catch the dripping water...
 
Depending on the wind conditions. Since their is no real way on alot of stoves to shut the vent/exhaust right off. If the wind is blowing the right way it will blow right in. As you are probably going to have a elbow or 2 in your system it will decrease this but not eliminate it if the wind is right
 
Thanks for the replies. I must have misread something that made me think only some stoves were "closed loops." Had it in my head that Harman and one other mfg were the only ones that were "truly closed" for some reason. Makes sense that an OAK would make a closed loop, rather than open up a direct line to the outdoors. Cheers
 
Depending on the wind conditions. Since their is no real way on alot of stoves to shut the vent/exhaust right off. If the wind is blowing the right way it will blow right in. As you are probably going to have a elbow or 2 in your system it will decrease this but not eliminate it if the wind is right
But still not leaking air into the house Pellet stove has the intake air sealed to combustion chamber. Like mentioned before by others if the door is closed the air coming thru the OAK will find its way out thru the exhaust/chimney/vent. Many wood stoves let the outside air into the house but i am almost sure that is not the case with pellet stoves now a date.
 
Now, some has an air wash for the glass that get the air from the room but the air infiltration from outside when in no operation is minimum to almost nothing. I don't know if is enough to take into consideration.
 
The quadrafire cb1200 pedistal base is its oak chamber. The oak tube hooks to the bottom of the stove base via a mount plate and the base needs to be sealed to the hearth. And cold air will come in when stove is not in operation.
 
The quadrafire cb1200 pedistal base is its oak chamber. The oak tube hooks to the bottom of the stove base via a mount plate and the base needs to be sealed to the hearth. And cold air will come in when stove is not in operation.
Are you saying even if the base is sealed to the hearth cold air can come in?

This is what I’m wondering about, and is what one dealer warned against in a basement install. Due to the stack effect there could be lottts of cold air coming in if that’s the case....

So it seems maybe I was right about thinking I read some stoves but not all were truly sealed, anybody know any more about that?
 
The quadrafire cb1200 pedistal base is its oak chamber. The oak tube hooks to the bottom of the stove base via a mount plate and the base needs to be sealed to the hearth. And cold air will come in when stove is not in operation.
But a seal rope is available to stop that condition. Right?
 
Yes you can use a flat gasket to seal it to the floor but you will have to go inside the back of the stove and seal up all the gaps with high temp sealer. It wont have a draft but the stove will be cold. I run mine without the oak so i dont have cold stove syndrome. I have enough traffic and air leaks in this old house its never been an issue
 
Air will come into the a stove thru the 2 openings to the outside. The exhaust pipe and the OAK.
This air is not warmed when the stove is off. I have never seen a pellet stove that is completely sealed. Cold air leaks around the door, the door for the ash pan and the body of the stove stays cold from the outside air coming in from the exhaust and outside air pipes.
 
Cold air leaks around the door, the door for the ash pan
If that is the case you should replace your gaskets cause it's not supposed to leak thru those areas at all. The leaks thru those areas as you mentioned cause poor performance when it is in operation.
 
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Outside air is pulled thru the vent and stove only when the combustion blower is running. When the stove is off the outside air vent is a dead air space and not likely to leak any air into the living space unless you have the door open on the stove. I consider it a closed loop.
That’s true on stoves that actually have a port on the back of the firebox like Harmans but for something like a Breckwell or quadrafire your basically just pointing your oak in the right direction. Most installs don’t need one and in a lot of cases they lead to problems( more moisture, more bugs, cold air) I laugh every time I see someone recommend one on every stove so you don’t turn your home negative with your tiny draft fan.
 
Thanks for the replies. I must have misread something that made me think only some stoves were "closed loops." Had it in my head that Harman and one other mfg were the only ones that were "truly closed" for some reason. Makes sense that an OAK would make a closed loop, rather than open up a direct line to the outdoors. Cheers
I think it's the other way around, there are some stove models that bring cold air into the vicinity of the air inlet of the stove, it's done behind shrouding . Probably more models with a direct hook up. But if you had one of those stoves without DHU you could do as others have done, just cap off your oak when the stove isn't in use in cold weather.
 
I put a brass ball valve inline on my OAK. I mostly use it when shutting down to clean so the cold air isn't blasting into the house with the stove door open. It remains closed when the stove is not in use including all summer.
 
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Most stoves do not have a sealed OAK-to-exhaust system, allowing OAK air to leak into the home. To determine if the OAK is sealed from the room, look inside the stove cabinet. A sealed system has the OAK pipe go into the firebox. An unsealed system just has the OAK pipe open-up to the inside of the stove cabinet, which then allows outside air to flow into the home thru the numerous openings/grills of the cabinet. My Ravelli/Ecoteck has a sealed OAK system.
 
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