Cold air return wall vent

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Dairyman

Minister of Fire
Nov 15, 2011
662
Southwest MO
I am thinking about adding a wall vent in between a bedroom and living room (where the wood stove is). My thoughts were that it would help with the bedroom temps and cut down on the cool draft from the hallway. I have done the fan trick and find it makes the master bedroom to warm without much improvement to the second. And makes it chilly sitting on the sofa.

Questions:

1: Is there any safety concerns?

2: Will it work?

I am attaching a sketch I have done on my phone , forgive me for its sloppiness. If a better diagram is needed I can make one up tonight. The blue circle is where the stove is and the red X is the proposed vent location.

Thanks, Mark

TEMPDOODLE.jpg
 
Are you talking about a strictly passive vent or an in the wall fan? I have an in wall fan (Home Depot online around 75 bucks)that is 2 speed and hard wired. It forces a draft between the room where my stove is and an attached greenhouse. My experience was I got very little draft without the fan - even with the temperature difference between a high 70s stove room and the 55 deg greenhouse through a partially open window. Will a passive vent make a difference in your setting? Somewhat. Will it give you a significant boost in temps? Not based on my experience.

So far as safety .....the general rule seems to be that you want to blow the cooler air towards the stove room not the warm air into the cool.
 
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I would consider putting in a wall fan on the stove side (high) and use the stud cavity as a plenum, then put the return grille (low) on the bedroom side. That should set up a nice convection loop by blowing the cool air toward the stove. It will be replaced by warm air via the hallway as long as the bedroom door is open or at least has a gap at the bottom. There are fans made just for this purpose.
 
So far as safety .....the general rule seems to be that you want to blow the cooler air towards the stove room not the warm air into the cool.

Could someone elaborate on this? Is it because of the possibility of blowing sparks around if something happened to fall out of the stove?

I have been considering a few ideas to move heat around better from our insert.

What about if the air intake is high up, since heat naturally rises anyways. I know it's harder to make hot air go down, but would this alleviate the safety concerns?
 
I believe the logic is that blowing hot air out risks spreading flame/sparks/smoke more rapidly.
 
I have the same set up your are talking about with my gas stove. Its on the other end of the room. Its 6x10 louvered vent on top threw the wall. The gas furnace vent is threw the wall on the bottom forced air it feeds both the living room and kitchen. I find it will keep the kitchen area at 60 deg.F . You can feel some hot air coming out the top vent, The ciealing temp above vent is 85 deg.F on the side of the room with stove. If I open the Door to kitchen it will drag my gas heating stove living room temp. way down. The little stove cant keep up with it. The only draw back is the living room with stove you get about 1 foot above floor that is always cold feet freeze, I mainly did it to keep the water pipes from freezing. So I dont have to use the big boy gas furnace. I also have a ducked cold air return from the kitchen to the the gas stove blower system I am using a 50 cfm bath fan mounted on the floor opposite end of the kitchen. It evens out the cold floor in the living room. Wood heat puts out more BTUs so it should help some.Make sure you box in the top vent threw the wall and insalate around it. Good luck.
 
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Could someone elaborate on this? Is it because of the possibility of blowing sparks around if something happened to fall out of the stove?

I have been considering a few ideas to move heat around better from our insert.

What about if the air intake is high up, since heat naturally rises anyways. I know it's harder to make hot air go down, but would this alleviate the safety concerns?

Code does not permit a return air vent to be less than 10ft away from the stove. However, a supply (delivering cold air from the adjacent room) is not under any restriction.
 
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