OAK questions

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1kzwoman

Minister of Fire
Dec 27, 2013
558
West near Yellowstone
I am debating an OAK install for my Harman TL200/Exception stove.
My home is well insulated and well sealed.
My stove burns well, but OAK has a good argument overall.
I see that some people use air from crawlspace in an indirect OAK.. to help with back draft, condensation, heat loss when adding air.
Anyone have experience with this stove and OAK?
Thanks
 
Coming from a crawlspace should pose no problem at all and may even help (no frost on piping in very cold weather).
 
The OAK will also help in pressurizing of your home, so if you have any air leaks, open door or window, more warmed air will leave your home and less cold air will come in.
 
The OAK will also help in pressurizing of your home, so if you have any air leaks, open door or window, more warmed air will leave your home and less cold air will come in.
Huh?
 
Warm air is lighter and takes up more room then cold air. With an OAK you aren't using your warmed air for combustion. The OAK supplies outside air and therefore pushing warm air out of your house rather then pulling in cold air to replace combustion air.
 
Coming from a crawlspace should pose no problem at all and may even help (no frost on piping in very cold weather).

I don't have an OAK so I am trying to learn about them also. If air is being drawn from a crawlspace, would replacement air get drawn in from outside? I know that crawlspaces are not air tight but in cold climates people seal the vents to prevent freezing. Is it so minimal it doesn't matter.

Good luck with your stove 1kzwoman.
 
Warm air is lighter and takes up more room then cold air. With an OAK you aren't using your warmed air for combustion. The OAK supplies outside air and therefore pushing warm air out of your house rather then pulling in cold air to replace combustion air.


Never heard all that before.
How much air can be coming through the OAK into the stove? I would not think all that much ,surely not enough to do what you're saying.
I mean the OAK is hooked directly to the stove. How can that effect the room pressure?
I'm a old dog but maybe I can catch on..lol.
 
My OAK comes directly from the outside and on very cold days, frost accumulates on it, melts and puddles under the stove. However, I posted the issue here yesterday and already have a solution for this. I would think using warmer air from an unheated crawlspace might be a better option if it's available.

I like the idea that supports the OAK (though know some very smart people also say it's unnecessary), and now with this solution to the frost-up and melting feel even better about it.

I'll post the link to the earlier discussion here in case it's helpful to you: https://www.hearth.com/talk/threads/frosty-oak.121001/#post-1620826

Good luck!
 
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From what I read OAK's can help in very tight house's.
If you have big exhaust fans in your tight house I guess the OAK is even more valuable.
They are also needed by most town codes for mobile homes.

But understand this is from stuff I mostly read on the net so take it with a grain of salt! lol
 
Never heard all that before.
How much air can be coming through the OAK into the stove? I would not think all that much ,surely not enough to do what you're saying.
I mean the OAK is hooked directly to the stove. How can that effect the room pressure?
I'm a old dog but maybe I can catch on..lol.

I know that this picture is from the manual from my pellet stove, but I believe it to be a good diagram showing what happens with positive and negative air pressures within the home. If you utilize an OAK, you will force hot air out of the home. If you use air from within the home for combustion (no OAK), you will draw air from outside to come through any point where it is possible that air can penetrate the home.

I looked up the manual for the TL200 and did not see this type of explanation for an OAK.
 

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I know that this picture is from the manual from my pellet stove, but I believe it to be a good diagram showing what happens with positive and negative air pressures within the home. If you utilize an OAK, you will force hot air out of the home. If you use air from within the home for combustion (no OAK), you will draw air from outside to come through any point where it is possible that air can penetrate the home.

I looked up the manual for the TL200 and did not see this type of explanation for an OAK.
I think you're reading to far into it..over analyzing it.
If what you think is true why would any stove manufacture even put a OAK connection on their stove?


With a OAK you would think the stove would be a sealed system. Combustion air coming in from outside and exhaust air going up the flue.
In other words..static, except for the stove heating the house.
I don't have a OAK or a need for one. My house is not small and air tight.
 
I did not have the same stove, but I did have an outside air intake to feed the stove rather than pulling air from inside the house. The outside air feeds combustion and then goes up the chimney and not into the house. None of the air from the OAK entered my house - nor pressurized it.
 
For my stove, installing an OAK eliminated problems with cold starts. I have no problems with draft when the chimney is cold, even on mild, rainy days. I ran the stove without an OAK for a year or two and filled the living room with smoke more than once. I have the same stove in our basement without an OAK (too difficult for me to install). I have to burn some paper in the clean out of the chimney to get a good draft started when the chimney is cold. The only disadvantage of an OAK is cold air entering the stove when your not burning. I stuff insulation in the stove pipe and outside vent during the summer.
 
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