Outside air kits for a drafty house

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deere317

New Member
Nov 23, 2014
35
Cincinnati Ohio
Lately I've bin throwing the idea of adding an outside air kit to the heating arsenal. After reading a few post it seams that there is a mixed opinion on them .
My situation is I have a 80yr old cape code that is less than air tight. I've worked on sealing up the major leaks and adding insulation to the attic and knee walls but I am wondering if the draft from the stove is creating a vacuum and drawing In more cold air.
So the question is will an Oak help eliminate drafts from old windows and door ending the fight to balance out the temperature difference.
 
I recently fed outside air to the rear of the stove and its working Stella.

Not I repeat Not an OAK, the stove still pulls room air for combustion, the air is fed to the rear and is subsequently drawn into the fans.

I was chasing drafts for ages in the living area, now I do not have any as the cold air is not being forced into my home. Infact, we have a slightly positive pressure scenario now which is pushing warm air out. I can live with that.

It's kinda funny, I have a cold air feed behind the stove but I dry walled over it on the advice of the dealer 'Your basement will be leaky' he said. Well Iam gonna pull the drywall this summer and re-connect the thing up. Still debating on actually feeding air to the stove or just direct the air to the fans/intake as this has solved my negative pressure problems.
 
So you piped it directly to the blower. Does that effect the temp off the blower

No not exactly.

I had a spare 4" outside vent comming through the rim joist. I ran 4" duct Down behind the stove, the pipe is terminated around 2' from the ground.

I noticed the left blower shroud is slightly cooler to the touch but the heat pushed over the stove is equal between the two.

I was thinking about pulling a fan shroud and making a direct intake to the fans but it would probably cause a few problems.

Edit: To put it another way.

I have allowed the home to breath with atomospheric pressure just like opening a window except the cold air entering the basement is drawn over the stove.
 
Modern stoves only draw air around 30-50 cfm in normal use. (open fireplaces can draw maybe 500 cfm). Whether that's enough to notice a change in your house is hard to say, but I don't like the idea that the stove is pulling any amount of cold air into the house from outside. Seems counter productive to me.

40 cfm is less than a bathroom fan, but it's still enough to exchange the air from a 1500 sf house in about 4 or 5 hours.
 
After reading a few post it seams that there is a mixed opinion on them .

Nobody has ever been damaged by an outside air connection. Adding an OAK may have failed to solve a particular issue but there is no drawback. Show me a backdrafting OAK setup which expels smoke out of the intake and I'll buy you a beer. It just doesn't happen like that. Many people are just too lazy to install the OAK so they make up these excuses. Sometimes you can't install an OAK due to building constraints or aesthetic desires.

Modern stoves only draw air around 30-50 cfm in normal use. (open fireplaces can draw maybe 500 cfm). Whether that's enough to notice a change in your house is hard to say, but I don't like the idea that the stove is pulling any amount of cold air into the house from outside. Seems counter productive to me.

40 cfm is less than a bathroom fan, but it's still enough to exchange the air from a 1500 sf house in about 4 or 5 hours.

The stove equipped with an outdoor air supply does not pull any cold air into the house, actually, a lack of a connected air supply is what pulls cold air into the house to make up for all of the conditioned air being sucked out by the stove. You've got it perfectly backwards.
 
The stove equipped with an outdoor air supply does not pull any cold air into the house, actually, a lack of a connected air supply is what pulls cold air into the house to make up for all of the conditioned air being sucked out by the stove. You've got it perfectly backwards.
Maybe I wasn't clear, but I am a proponent of OAKs and understand what they do and I agree with you. I was just trying to point out to the OP that in his case, installing one now may or may not make a noticeable difference, but I always encourage their use. I don't like a stove pulling in air through the house, and an OAK installation makes sense in nearly any case.

I've seen some websites that illustrate potential problems but I think they are pretty rare examples. There can be problems stemming from poor installation, but if it's done right, it's usually the right move. Sorry if it seemed that I was discouraging the OP. As I said before, 40 or 50 cfm doesn't sound like a lot, but without an OAK, it does pull all the air out of a typical house after several hours, which is air that you just heated up.
 
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Yeah the point of bringing in make up air is Atmospheric pressure changes constantly from high - low - high Etc.

IDE rarther introduce out side air behind the stove to be warmed than have it enter directly into the living space. (Forced air return will start to draft)

Even an OAK will not prevent Negative pressure inside, It eliminates the heater from pulling room air but if the pressure outside increases then its gonna force It's way in regardless. The OAK won't prevent smoke from the firebox during reload either.

Next time you flush the toilet have a look at the water level in the bowl. The lower the better.
 
can"t put an oak ,but have air exchanger would that help?
If the home is very air tight, an air exchanger is useful if not necessary. Otherwise, I would avoid them. My son has one in the new house he bought and rarely uses it. When turned on, you do feel the fresh air coming into the house but it is definitely cool air.
 
Far from air tight, just thought it might stop air from sneaking in tour the farther ends oof the house
 
I think I will order one and see if there Is an improvement. Like highbeam said can't really hurt anything. Plus my stove is made to have it bolt right onto the air intak.
 
Thinking about installing an OAK when we put in the new stove but I have a question. Will the OAK cool off a stove faster then one without an OAK? Thinking about going with a stone stove but when away at work the fire will burn down. We do burn 24/7 but the furnace still comes on for a few hours when we are away or early in the am. If it cools it down faster then maybe an OAK is not good for a stone stove. Just asking because I have no idea and am always will to learn.
 
I have an OAK on my Hearthstone and the aux. is closed off so it gets 100% of the air from the OAK. My house was super air tight but that was 30 yrs ago so a bit less so now.

Basically, your combustion air HAS to come from somewhere. If you don't have an OAK, the air infiltrates from wherever the leaks are. That cold air is entering your house and will make the house cooler. The stove has to work harder to heat more of your house air. Someone posted that the amount of air for combustion is negligible but if you look at the amount of smoke exiting your chimney, that's exactly how much is entering through the cracks or the OAK.

IOW, I would rather have cold air coming into the stove than cold air coming into the house first, then the stove. With a stove at 500, heating that amount of air with an OAK will be negligible.
 
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