Outside Air Kit - Oak - My research after investigating

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Do you have an outside air kit attached to your stove?


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Here in Nova Scotia, there is another very good reason to have an OAK - radon gas. Having something in your house that creates a negative pressure increases the risk that radon gas will be pulled into your basement more efficiently. With the OAK, that risk is reduced. I have radon remediation as well as OAK kits on both stoves (basement and main floor) any my radon numbers are well below risk level. Not a risk in all areas, but it is for some.
 
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Even with low humidity in my house (~25% in the dead of winter) I get frost on my OAKS. I have wrapped insulation around them
Here in Nova Scotia, there is another very good reason to have an OAK - radon gas. Having something in your house that creates a negative pressure increases the risk that radon gas will be pulled into your basement more efficiently. With the OAK, that risk is reduced. I have radon remediation as well as OAK kits on both stoves (basement and main floor) any my radon numbers are well below risk level. Not a risk in all areas, but it is for some.

That is a great reason - Radon is also a concern for some areas of new England (and most of NH). Never even thought of that since I don't know if either of my houses had/ have radon, and don't care to test. (and please, no safety police getting on my case - I have no kids, no family and no friends, so it's just me breathing the air here).
 
What does one do when the Stove is in the middle of the room? Its hard to Install a OAK where my stove is located without tearing down drywall
Any option of running it down and out? May have to resize up if it is a long run. What kind of stove?
 
Up and along the floor joists but likely that would require pulling drywall unless there are sections of the basement that are unfinished or have a suspended ceiling. I am judging you are currently running the stove? How is it performing?

ps ... do recall someone posting a system that brought outside air into basement on exterior wall that had a U configuration extending toward the floor. Will see if I can find the thread...
 
To OAK or to not OAK. I understand the differing of opinions people have. I OAK because I understand the benefits. What I don't understand is that people say that their homes are leaky and drafty and do nothing about it. Imagine the benefits if they sealed up their homes.
Oh I am doing something about it, but only a drop in the bucket really. To seal up my house would probably require gutting the entire thing, something I'll never do in part because I don't plan on staying in this house, and well because the walls are finished nicely inside and out. It'd be different story if it was in desperate need of cosmetic update as well. I did gut the last two rooms that were quite old plaster walls, half of the upstairs of the old section of the house didn't even have any insulation on the roof so that was my priority. I was getting a lot of air infiltration into the common wall between the old house and the new addition. That is basically now an interior wall right through the center of the house. Cold air was blowing right in there and circulating through the whole house basically. I found one small section where two roofs meet at funny angle that left a large cavity between that had vented soffit, that vented straight into that wall the runs through center of the house. I sealed up the venting but there is still air getting in there could be getting in between where the roofs meet at various points, kind of hard unless I am going to rip up almost brand new standing seam metal roof. I can't wait to dump this place and maybe design my own efficient home.
 
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Would just like to mention that I finally put in an OAK on my shop stove (Castile Serenity) that I fabbed from various metal leftovers and I love it! Makes a noticeable difference. Must just be better to blow hot air out the cracks than suck in cold air, ;)
 
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I've had an accentra insert for 6 years. Ran it two years before installing an OAK. Decided on an OAK in 2016 and it seemed better, but not quantifiable. This season, after cleaning, I noticed it wasn't burning right. After pulling it out again, I discovered I pinched off my homemade OAK on reinstall. Decided to just run without it. Major difference in draft and temperature in the house. It used to heat up 3 rooms, now it only kept one warm. Decided this morning to reinstall my OAK. World of difference.

But the plural of anecdote is not data, so as a professional mechanical engineer who has worked in HVAC and industrial district heating plants, I started to play with some numbers to see if I could get to the bottom of it.

Using assumption of 0 degree OAK intake air vs. 70 degree room air and assuming the combustion fan pulls about 75 CFM, I figure the stove needs to produce an additional 5,670 BTU per hour to heat the outside air coming in the home (or reduces stove heating capacity.) That being said, the stove with an OAK would need to burn a few more pellets to pre-heat the 0 degree outside air to be an equivalency. But, with all puts and takes at an assumed 80% efficiency, I still figure the OAK saves about 1,200 BTU per hour or 28,000 BTU for a full day run, so that would be about 3 pounds per full day run savings.

I don't care much about the miniscule savings, but I absolutely am convinced an OAK kit is the way to go based on drafts and family comfort. The fact that I've got some numbers to back me up makes me feel better.

Trent

  • "We can't solve problems by using the same kind of thinking we used when we created them."
  • -Albert Einstein
 
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I've had an accentra insert for 6 years. Ran it two years before installing an OAK. Decided on an OAK in 2016 and it seemed better, but not quantifiable. This season, after cleaning, I noticed it wasn't burning right. After pulling it out again, I discovered I pinched off my homemade OAK on reinstall. Decided to just run without it. Major difference in draft and temperature in the house. It used to heat up 3 rooms, now it only kept one warm. Decided this morning to reinstall my OAK. World of difference.

But the plural of anecdote is not data, so as a professional mechanical engineer who has worked in HVAC and industrial district heating plants, I started to play with some numbers to see if I could get to the bottom of it.

Using assumption of 0 degree OAK intake air vs. 70 degree room air and assuming the combustion fan pulls about 75 CFM, I figure the stove needs to produce an additional 5,670 BTU per hour to heat the outside air coming in the home (or reduces stove heating capacity.) That being said, the stove with an OAK would need to burn a few more pellets to pre-heat the 0 degree outside air to be an equivalency. But, with all puts and takes at an assumed 80% efficiency, I still figure the OAK saves about 1,200 BTU per hour or 28,000 BTU for a full day run, so that would be about 3 pounds per full day run savings.

I don't care much about the miniscule savings, but I absolutely am convinced an OAK kit is the way to go based on drafts and family comfort. The fact that I've got some numbers to back me up makes me feel better.

Trent

  • "We can't solve problems by using the same kind of thinking we used when we created them."
  • -Albert Einstein
Hi Trent
You do not have to compromise by using an OAK with incoming air at 0 degrees! I will not do that!
I use the Selkirk DT or Direct Temp venting with a 3rd wall to bring that outside air in and down to the stove around the hot flue pipe to dry And preheat the incoming outside cold and/or damp air!! Thus increasing the whole system efficiency by 10% :)
This works very well for me and my friends who have installed it!!
 

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Hi Trent
You do not have to compromise by using an OAK with incoming air at 0 degrees! I will not do that!
I use the Selkirk DT or Direct Temp venting with a 3rd wall to bring that outside air in and down to the stove around the hot flue pipe to dry And preheat the incoming outside cold and/or damp air!! Thus increasing the whole system efficiency by 10% :)
This works very well for me and my friends who have installed it!!

I'd love to have concentric intake, but the insert and flue pipe is already there and installed, so it'd be too much to retrofit at this point. Next stove for sure will be this way.