Outside Air Kit (OAK) Install - how to make it look nice on interior wall?

[John_M]

velvet foot,
I am clueless on the HRV's.
John_M

 

[velvetfoot]

Well then, that makes two of us!
I believe it supplies fresh air and exhausts stale air through a heat exchanger which extracts some heat so it's not a total waste.
It's an indoor air pollution thing.
I don't know how they are controlled or if it can supply makeup air or anything like that. If it can neutralize positive or negative pressure in the house in a controlled way via its powered fan, it would seem that would suffice for an appliance.
That's a big if, and I'm clueless after all.

 

[MountainStoveGuy]

The EPA has too many guidelines.

If you want to exchange your house air for outside air then there are devices like the HRV to do that. If you want an uncontrolled leak then you can open a window. If you want a situation where your solid fuel burning appliance will always have sufficient combustion air and is not affected by the homes air pressure then get an OAK. There is some benefit to having completely independent air systems for each appliance including your home. Notice how these new gas furnaces have outside air intakes? Also the coaxial direct vent pipe for gas stoves? Even water heaters now have the intakes outside.

OAKs are affected by wind direction. gas which dont stink when flue leaks has a stringent code which tends to repeat "non-airtight construction" in the specs. CODECHECK book @ HD is a grreat reaD

The OAKs are not affected by wind any more than your chimney is. That's more bad woodheat.org info regurgitated here. Show us your experience. If you install the OAK to a vented crawlspace then wind couldn't possibly be an issue.

Highbeam, not one to argue here. Back a few years ago in a heated OAK debate (hell, i think Elk was involved with this one, i called Jotul. One of there biggest concerns with OAK's was the potential affects on how wind can adversely affect OAK's. Not sure if they changed there stance on that, and FWIW, its the only manufacture i called if i remember correctly that i specifically asked the manufacture there opinion on OAK. I think i need to find that thread!

 

[MountainStoveGuy]

This thread was a epic. roo, elk mrsweep etc. . The jotul references are on page three.
https://www.hearth.com/econtent/index.php/forums/viewthread/2496/

 

[madrone]

wow. My eyes hurt after that thread. Thanks. I still don't know if I need an OAK, but thanks!

 

[Slow1]

Both of these threads can make my head spin. Geez. I started off wondering how to make it look pretty... Now I see that not only might it be a 'don't care' deal it could (in at least some opinions) do anything from prematurely cool my stove after burns to burn my house down (ok, the last one seems to have been debunked).

Thanks to everyone who has pitched into this discussion - although clearly there isn't a consensus here on what the right thing to do, and there may not be one right answer, I appreciate hearing multiple sides of the debate and getting feedback from the experienced.

As to my plans? I am going to try my stove without it for the time being and see how things go. IF there is a problem then I'll see what the problem is and where the troubleshooting (and helpful folks here) leads me - if it takes me to an OAK as a solution the debate will likely rage again

 

[MountainStoveGuy]

i told ya that no matter what, there will no information here that will tell you weither or not you want or need OAK :ahhh:

 

[Highbeam]

You're right about that MSG. I don't think anyone is saying that you have to use an OAK, not even a real profound reason that you really really should. Also no real profound reason that you shouldn't.

Still falls under the "might help, can't hurt" category.

 

[moosetrek]

Why not buy the OAK kit heat shield and put a temp blockoff plate on it to protect the wall? The pull the screws or whatever you use, and install the kit later if you want? Ours is over 25' of pipe for the OAK, and no issues at all. Drafts fine, I can feel how cold the pipe gets coming into the stove. I'd rather it pull the cold winter air fmor outside than the warm air from inside, but probably not much difference. Also, I used 1" larger diameter OAK hose/pipe than required due to the length of the run. Used black stove paint and it looks OK along the back of the stove.

Good luck!

 

[semipro]

So... anyone have first hand bad experience with an OAK to share?

Yes. To your original question first though: I've seen metal drier vents used on the outside wall (with the flap removed and bug screen inserted instead). There are also square trim plates to make the wall hole look better. Painting the pipe with some high heat paint should make it look better. High heat paint is only needed because of the heat the stove radiates, the air inside the vent should be cool. I'm not sure if this meets code but I'm sure someone will chime in if it doesn't. If your house is humid in the winter (most aren't especially if you burn wood) you should consider condensation issues with your OAK.

I've had practical experience with 3 different OAK setups in 3 houses.

1st house) A tightly built ranch, well insulated with two different stoves in the basement. I measured an immediate (within 15 minutes) temperature increase of several degrees on the ground floor of the house when I enabled a drier outlet near the stove as an OAK (temporarily). This vent was on the north side of the house. I figure air that was coming in around doors, windows, and elsewhere was now coming in through the OAK. This definitely warmed the house but the question remains as to whether the efficiency of the stove was decreased because colder outside air was entering it. The net energy effect may have been a wash. Being a tight house though I worried about backflow when bathroom or kitchen vents were on so I installed a permanent OAK.

2nd house) Questionable tightness house with a VC stove in the great room. Based on my previous experience I drilled a hole in the floor behind the stove to the vented floor space below and observed the air flow. The house must have been somewhat tight as there was a substantial airflow entering the house through this hole when the stove was burning. This flow seemed independent of wind outside. We left the hole open when the stove was on and covered it when it wasn't. We never installed a connection between stove and hole. Some screen was inserted into the hole to keep bugs out.

3rd house) Big Jotul in the basement of a 4 level, somewhat tight house. Based on previous experience I installed an OAK right off. It exits through a side wall to the northwest side of our house. If you disconnect one of the OAK connections while the stove is burning you feel a substantial airflow between the 2 ends. Has operated for almost 9 years flawlessly.

My thoughts on OAKs in general:
- Their use may or may not result in a net energy savings as colder air entering the stove may negate energy savings elsewhere. I'd love to see more info on this.

- They may make the house seem more comfortable as less cold air enters around doors and windows in living areas.

- If you like control of the air entering your house you should install one. I do.

- I don't like the smell of the unused stove on rainy days. I think use of an OAK minimizes that backflow of air into the house reducing the smell.

- Based on my experience an OAK vented to an outside wall works great. That said, all mine were installed in northern walls which would usually have been exposed to positive wind pressure due to prevailing winter winds.

- If you have a very tight house you need an OAK. There are too many fans, gas water heaters, and other things competing for a limited amount of air. Having your wood stove or any other combustion device competing with others for fresh air is not a good idea.

If you experiment with yours let us know how it goes.

Good luck.