Outside air intake, can it be through "mud room"?

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Gina S

New Member
Nov 12, 2018
4
crestone colorado
New here and to pellet stoves.
We have few options for routing for an outside air intake hose to pellet stove. We have no basement.
1. Option One: Run along wall for about 10 feet into a mud room (concrete floor foyer between outside and main house. Currently, a bathroom fan vents near the ceiling out to the same space . Room is about 7 x 10 ft with 3 windows and 1 door. Can leave windows slightly open. Is this dangerous or inadvisable to intake from mud room?
2. Option Two: Run vertically up, parallel to vertical chimney, but I fear this will be too near the chimney. Is this dangerous or inadvisable?

We are at 8,000 feet, and while I see some posts indicate outside air intake is not necessary, it seems to me oxygen needed at that altitude. Is that because we lose efficiency or is it safer to have the air intake? If it's only a question of efficiency, then perhaps I can leave off the outside air intake.
Anyone in similar circumstances who can advise me?
Thanks so much~
 
The issue is when you do not install a outside air kit the stove will pull air from every crack or gap in your home. Now running it out to your mud room i would not really recommend, same with your bathroom fan that is just putting damp air into a enclosed area and going to create issues in the future. You can get wall thimbles that also have the air intake built in. Or just drill a hole and mount it close to your stove
 
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My stove gets fresh air from a 20 ft long 4" dryer vent hose run to the inside the attached garage. Plenty of leaked air pulled from that space.
I do have 6 ft of metal intake connected to the stove end of it..
That all said, running the fresh air vent to the outdoors is still the best option.
 
Does your state have a code for stove installation?
What does your insurance policy state?

One main safety issue of not having an OAK, is if the power goes out, the fans stop, and the fire smoke can go backward through the intake and fill the house with smoke.
On the efficiency part, yes, the stove does have a fan that pulls air into the fire then out through the chimney. This means it is removing air from inside the house and pushing it to the outside. That air must be replaced. This means through windows, doors, or any vents and leaks the house has, including a cooking stove hood and/or a dryer vent. Both of which btw, work the same was as your stove, pulling air to the outside.

My neighbor's house has natural gas heat and gas water heater. They were installed professionally to state code at that time. There is a floor vent next to the two appliances. I asked why? It is to allow combustion air ingress.

You mention vertical chimney, so I assume this means the chimney goes up through the ceiling, passing through the attic, then though the roof? If your attic has vents, then see if you can pull the air from the attic?
 
The issue is when you do not install a outside air kit the stove will pull air from every crack or gap in your home. Now running it out to your mud room i would not really recommend, same with your bathroom fan that is just putting damp air into a enclosed area and going to create issues in the future. You can get wall thimbles that also have the air intake built in. Or just drill a hole and mount it close to your stove
Thank you so much for your reply. Our situation is that the pellet will sit next to an adobe brick wall, on the other side of which is the bathroom, then after that sits the mud room. We aren't positioning it to an outside wall because it's replacing a wood stove that resided there. Most of our southern wall is passive solar windows, so we have limited options to place the stove.
Very much appreciate you taking the time to reply.
 
My stove gets fresh air from a 20 ft long 4" dryer vent hose run to the inside the attached garage. Plenty of leaked air pulled from that space.
I do have 6 ft of metal intake connected to the stove end of it..
That all said, running the fresh air vent to the outdoors is still the best option.
Thank you for the example of your situation. We have limited "walls" that adjoin the outside, The southern length is all passive solar window, and so while the best potential for placement uses the former wood stove chimney, the closest outside vent is the mud room or beyond, but I'd need to run up 9 ft then over about 12 to access "true" outside rather than drafty mud room. I'm glad to know you use that length of vent without issues.
Thank you again for sharing your example, I really appreciate it.
 
Does your state have a code for stove installation?
What does your insurance policy state?

One main safety issue of not having an OAK, is if the power goes out, the fans stop, and the fire smoke can go backward through the intake and fill the house with smoke.
On the efficiency part, yes, the stove does have a fan that pulls air into the fire then out through the chimney. This means it is removing air from inside the house and pushing it to the outside. That air must be replaced. This means through windows, doors, or any vents and leaks the house has, including a cooking stove hood and/or a dryer vent. Both of which btw, work the same was as your stove, pulling air to the outside.

My neighbor's house has natural gas heat and gas water heater. They were installed professionally to state code at that time. There is a floor vent next to the two appliances. I asked why? It is to allow combustion air ingress.

You mention vertical chimney, so I assume this means the chimney goes up through the ceiling, passing through the attic, then though the roof? If your attic has vents, then see if you can pull the air from the attic?
Thank you so much for your reply and for the reminder to check my insurance! I haven't heard back from the county yet about the local regs. AFAIK, it's only manufactured homes that require the OAK, but I appreciate that reminder as well and I'll follow up on the state/county/local regs so I'm clear.
The vertical chimney goes straight to the flat roof (no attic) for a total rise of about 16 -18 ft (8 or so inside, then about the same outside above rooftop)

I'm so appreciative of this forum, and your reply. Thank you!
 
Thank you for the example of your situation. We have limited "walls" that adjoin the outside, The southern length is all passive solar window, and so while the best potential for placement uses the former wood stove chimney, the closest outside vent is the mud room or beyond, but I'd need to run up 9 ft then over about 12 to access "true" outside rather than drafty mud room. I'm glad to know you use that length of vent without issues.
Thank you again for sharing your example, I really appreciate it.

I have my stove vented into a chimney with a good draw so there is no worry about smoke going back in the fresh air supply vent. My insurance co already checked my stove install and I`m covered.
Again , you might still want to make sure yours is installed correctly and legal.