Is OAK a myth? [article] Discuss.

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movemaine

Minister of Fire
Nov 28, 2011
514
Central Maine
movemaine.com
Despite the fact that it is enshrined in some building codes and its adherents are often vocally forceful, there is no scientific evidence to suggest that outdoor air supplies, either direct to the combustion chamber or indirect supplies to the living space, are reliable and effective remedial measures for combustion spillage from the appliance for which the supply is intended.

http://woodheat.org/the-outdoor-air-myth-exposed.html

But I think this would largely pertain to wood stoves more than pellet stoves....
 
Yep, not a thing to do with pellet stoves.
 
While I don't subscribe to the belief that an OAK is the holy grail, the article doesn't mention anything about pellet stoves. Would have liked to see sources in the article.
 
Pellet stove has forced exhaust which changes things. I will say that In my case not having an oak was beneficial as my home was tight w a humidity problem in the winter. The forced exhaust of the stove fixed that problem.:)
 
Yeah, I'm of the mind and OAK is an improvement, and with the enclosed combustion cycle, the above article shouldn't be an issue.
 
Yes, they talk about wood stoves not needing much combustion air. Pellet stoves on the other hand that have 85 CFM combustion blowers use alot more burn air. Unfortunately if air taken from the outside is very cold or very damp, IMO it is a problem. Cold air needs more energy to heat and damp air makes the pellet ash stick together more. Windy air can also be an issue.
 
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It does take more energy to heat outside air, but not by much. The combustion air temp difference is extremely small (50 deg f) compared to the flame temp (1500 deg f). In contrast, pulling heated air out of your home to use for combustion creates negative air pressure which pulls cold air from outside into your home. The stove has to work more to keep your home at a reasonable temp. This is less efficient than using an oak
 
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Am I the only one who kind of chuckled when they read this?

Well, He is actually right. A strong breeze at the OAK opening may create a negative pressure zone. It may cause the vac switch to trip the controller on the units.

I saw this in an install, I didn't believe it until we disconnected the OAK on a windy day. Stove ran fine. Re-installed the OAK and within minutes the stove was loosing the vacuum switch every time a gust happened. You could actually hear the vac switch clicking. A standard dryer duct was used. I replaced the duct with a universal OAK kit with a shroud(I don't remember the brand name). It got better but on a heavy wind day it still is an issue. Its possible we will need to move the inlet location or try another OAK kit. I may try adding a 90* to the inlet?

If anyone hears of a high wind OAK let me know!
 
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Well, He is actually right. A strong breeze at the OAK opening may create a negative pressure zone. It may cause the vac switch to trip the controller on the units.

I saw this in an install, I didn't believe it until we disconnected the OAK on a windy day. Stove ran fine. Re-installed the OAK and within minutes the stove was loosing the vacuum switch every time a gust happened. You could actually hear the vac switch clicking. A standard dryer duct was used. I replaced the duct with a universal OAK kit with a shroud(I don't remember the brand name). It got better but on a heavy wind day it still is an issue. Its possible we will need to move the inlet location or try another OAK kit. I may try adding a 90* to the inlet?

If anyone hears of a high wind OAK let me know!
I wasn't disputing the validity of the statement, I just thought the phrase "Windy Air" was kind of humorous. Try using the description of windy air anywhere else in life. Only a pellet guy would understand the term...lol.
 
I'm still planning on an OAK. Maybe not this year, as I'm having the front door replaced and extra insulation blown in the attic - both of which have been big sources of heat loss in my house.

On nights when the temp was floating around 0 here in Maine, the stove was drawing in so much air you could feel the breeze standing in front of the door. A new door should rectify that.
 
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AN oak with trap door would make sense sort of like a draft tee for an oil burner. when the air pressure in the house drops suchas time when yu are running a dryer vented outside and a kitchen range hood,the trap door would open and supply additional outside air. normally a weighted trap door would remain closed. My house is very leaky but when other appliances are venting i can tell my stove does not draft well.
 
Hm... my oak creates a closed system within the stove. The only space open to indoor air is the airwash - small gaps at the bottom of the glass. There's nothing for air pressure changes in the house that has the slightest effect on air flow through the stove, as far as I can notice. The oak opening is on the SE side of the house, about 2' off the ground and sometimes exposed to pretty good gusts of wind. The combustion blower seems stable enough to overcome any pressure changes on the oak opening - never had a vacuum cutoff issue.
 
If anyone hears of a high wind OAK let me know!

This may even sound funnier!
In some ways, Selkirk DT is the only OAK that is better than no OAK at all! ! ! ! ! LOL

Selkirk DT is the best OAK for me!
 
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Any OAK is better than no OAK. The DT system is nice, but in a long run, it may hurt more than it helps. To much cooling of the exhaust is bad. Temps still need to stay high enough to keep the exhaust from condensing and creating the Icky Sote!! :cool:
 
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Any OAK is better than no OAK. The DT system is nice, but in a long run, it may hurt more than it helps. To much cooling of the exhaust is bad. Temps still need to stay high enough to keep the exhaust from condensing and creating the Icky Sote!! :cool:

Very True Dexter!
I know of one installation with an outside vertical run in a house on a hill near the ocean that is extremely cold and windy! Needless to say if the vent is not cleaned every month in the winter the pipe clogs and the stove dies!

This is exactly why the vertical run should be on the inside of the house or in a very well insulated chase! All these little improvements end up with a very well running pellet stove and a very happy pellet stove owner! :)
 
I wasn't disputing the validity of the statement, I just thought the phrase "Windy Air" was kind of humorous. Try using the description of windy air anywhere else in life. Only a pellet guy would understand the term...lol.

You have to watch wind direction even if there is no OAK. The same thing (stove shutting down with a vacuum fault) can happen in high wind conditions when you have the stove vented into the wind. We have it crop up on here every winter.
 
I wasn't disputing the validity of the statement, I just thought the phrase "Windy Air" was kind of humorous. Try using the description of windy air anywhere else in life. Only a pellet guy would understand the term...lol.

I got lots of windy air, I usually blame that on the dog/cat/kid! :p

I guess I got so used to don, I didn't get it. I was one of the few that could understand pook! Talk about windy air! ::-)
 
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I got lots of windy air, I usually blame that on the dog/cat/kid! :p

I guess I got so used to don, I didn't get it. I was one of the few that could understand pook! Talk about windy air! ::-)

Hey Jay, I have a test for you.

Take a bag of any brand of wood pellets that is a year or more old and compare it against a bag (Same Brand) from this years batch. There may be a difference in heat output? Do you have any bags you can do that with?
 
Hey Jay, I have a test for you.

Take a bag of any brand of wood pellets that is a year or more old and compare it against a bag (Same Brand) from this years batch. There may be a difference in heat output? Do you have any bags you can do that with?

I done that in the past and really haven't seen a difference with the old stuff. I have had pellets sit in my basement for 4 years and still burn as good as the day I bought them. On some new stuff I have seen a difference due to mill/fiber issues.

Are you having issues with stored fuel?
 
I done that in the past and really haven't seen a difference with the old stuff. I have had pellets sit in my basement for 4 years and still burn as good as the day I bought them. On some new stuff I have seen a difference due to mill/fiber issues.

Are you having issues with stored fuel?

I did on some Maine's Choice pellets that were 1.5 years old. They were in my garage and it is not really that damp. Oh well, it could be that the mill had a better drying process in the new batch?
 
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Probably batch consistently. I have had the PTL for over 3 seasons now and still the same. Same with some Somersets. . . But mine are all off the ground in dry environments. Even if the air was damp? I dont know how much it would matter? There are holes in the bag, but doubt the majority of contents would be affected
 
One thing I remember now is that, at first I brought a bag in from the cold garage and dumped it right into the stove. Then I brought a few bags into the warm basement for a few days and that seemed to help.
 
With an OAK, the house is hot and pushing air that already exists around.
without, the house is constantly looking for air to feed the stove and thus it pulls in cold air and drafts.
 
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