Dealer says No to fresh air intake. Pellet stove

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TravisX

New Member
Jan 9, 2023
2
Canada
My dealer says No to an OAK (outside air kit) for my Harman XXV pellet because it "draws in cold/moist air that will encourage soot/creosote buildup."
I have uncomfortable floor drafts in the basement room where the thing is. I can only try and stop up as many cracks and crevices as one can.
Plastic on windows etc etc. I get it. The stove needs air from somewhere.
Most of what Ive read is mostly positive for those who installed an OAK. How bad is the threat of soot buildup with an OAK?
Do I go by what dealer says or ?? Even Harman says its not required but is recommended for "all installations". And its required for mobile homes.

What about this: Stove is on one end of fully finished bsmt. Family rm. There's an unused bedrm close to it. 3 feet or so away near its left side back.
Was thinking of putting in a grill in the drywall there so the stove could get air from there instead of the way it is now - pulling air down the stairs and other cooler areas likely from the bsmt.
It wouldn't give it more air as such but it might "direct" the air it needs thru there instead of along our feet in the main bsmt area!
Above that bedrm is main floor hallway. I was thinking even then to put in another grill thru the floor so it would pull down cool air from there
instead of down the stairs as it is now. Ideas anyone?
Secondary thought. Has anyone also had luck (performance) with cutting floor vents to allow the warm air to rise up to main floor?
Am aware that insurance would likely frown upon it but disregard that for now. What about even blocking the cutout with i.e. drywall or metal?
Wouldnt that make it more "legal" Or putting in more smoke alarms?
 

jackman

Minister of Fire
Jan 15, 2013
686
Oregon
My dealer tried that too. They just want to take the easy way to finish the job faster. I told him to install the OAK.
 
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TravisX

New Member
Jan 9, 2023
2
Canada
My dealer tried that too. They just want to take the easy way to finish the job faster. I told him to install the OAK.
Possibly yeah. If moisture is the issue and its pretty damp winter air where I am, eastern Canada, how about then putting some kind of moisture absorbing "bag" or material over the intake pipe!!? Replace it now and then. Hmmm.
 

articcatbill

Member
Sep 4, 2016
93
central pa
I do not have an OAK in mine, it is located in my basement. But the OAK really does not have anything to do with heat circulation, just where the air for combustion is coming from, heat circulation is another issue.

When I first started using it I was a bit disappointed in the heat circulation. There were 2 existing 4x12 vents above the pellet stove that went to the floor in the dining room, but just relying on the heat rising didn't circulate much heat upstairs.

I bought 2 of these Tjerland RB12 fans

(Amazon product)

register booster fans for the 4x12 registers. Wow what a difference, it certainly balanced everything out and now I am very happy with the set-up. The upstairs and lower level family room are now consistent
 

mtnbiker727

Feeling the Heat
Mar 11, 2019
321
PA
I have a basement install. Every time I walk up the stairs I feel the cold air coming down the stairs. The cold air falls down the stairs because the stove is heating the air in the basement, and warm air rises. You want the cold air to return to the stove so that it can be warmed up and sent back up the stairs. You can open other holes in the floor, but the stairwell is huge compared to anything you're going to do, so the cold air will naturally flow down it.

If you're not using the stove to heat the upstairs, then shut the basement door.

As far as humidity, what's the humidity inside your house, compared to outside? In most places in the wintertime when the stove is running, the outside humidity gets very low, and usually the house gets low too, but not as low as outside.

If it's really cold outside, your stove works hard, sucking in a lot of air. If you don't have an OAK, it's pulling that cold air through every crack in the house, which then needs to be heated by the stove. If you have an OAK, then the cold air goes directly into the stove and gets warmed up before you feel the cold air.

I've seen lots of people on here comment that their stove burned a lot cleaner with an OAK.

I don't have an OAK, but I'm in a temporary living situation, so hopefully before my hair is gray, I'll have a permanent situation and will be installing an OAK.
 
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bogieb

Minister of Fire
Oct 31, 2014
3,297
South Central NH
I have an OAK on both my stoves. When the P61a was installed, they didn't put in an OAK (the install manual says it is strongly recommended, especially lower level and main level). I installed the OAK the next year. When I put in my main floor stove, I never didn't think about an OAK. When I first moved in this house, it was very "open" to the elements. I have been adding insulation, new windows etc and tightening up the house over the years (still nowhere close to what a new house would be, but much, much better now).

Never had an issue with soot build up. Both of the OAKs will get frosty in the deep of winter, but that doesn't seem to cause an issue. I do unhook the OAK from the stove, then plug the intakes once burning season is over. I also block the exhaust pipes.

As far as cutting vents in the floor - it may work it may not. For my house, it didn't work regardless of vent fans (up and down) and other methods to try to move the air. So now I have a bunch of holes in my nice hardwood floors (the ONLY thing that was nice about this house when I bought it), and a 2nd stove on my main floor when the P61a should otherwise be able to easily heat the grand total of 1,650 sq/ft.
 
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zrock

Minister of Fire
Dec 2, 2017
1,372
bc
definitely install the OAK otherwise every single draft in your home is going to be drawing in cold air. With the OAK you will be pulling all the air from outside and it will feel much warmer. I also find that when its colder outside my stove is more efficient
 

GrumpyDad

Minister of Fire
Feb 23, 2022
1,094
Champion, PA
definitely install the OAK otherwise every single draft in your home is going to be drawing in cold air. With the OAK you will be pulling all the air from outside and it will feel much warmer. I also find that when its colder outside my stove is more efficient
This is spot on!
The other day I was sitting in a rocking chair near two windows and it really felt like it was -20f out or something, and it was about 34f at that time. It was quite noticeable. My wife has been complaining about how cold she is and how disappointed she has been with the wood stove in the other room. But the thermostat on our furnace located in this room shows the proper temps. So there's a definite draft being pulled from those windows across from where she is sitting. I do not feel this in the stove room. The stove room is a new expansion, and is heavily insulated. These windows are double pane but are older, and long ago I covered them during the winter months because you could feel a draft sitting near them. But now, it's almost like there is an AC unit blowing on a really low speed.
 

3650

Minister of Fire
May 8, 2011
877
midwest
Yep. I have two pellet stoves in my house. One has and oak and the other one doesn’t. When I use the one without it feels like I have an open window somewhere.
 
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m159267

Burning Hunk
Mar 12, 2009
218
East-Central MO
My P38 is a basement install (since 2006) with a short 2' OAK. No creosote and very little soot. I do have the OAK insulated or the pipe will get heavily covered in frost during bitter temps. My take is any dealer that claims an OAK is detrimental is lazy and only wants the fast dollar. Install the OAK. BTW - the comment about a cold draft coming down the stairs is valid - I keep my door shut when running the stove.
 
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GrumpyDad

Minister of Fire
Feb 23, 2022
1,094
Champion, PA
Yep. I have two pellet stoves in my house. One has and oak and the other one doesn’t. When I use the one without it feels like I have an open window somewhere.
It would be interesting if there was a controlled study on this. I wonder when they test stoves for efficiency if it is done with separate air.
 
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johneh

Minister of Fire
Dec 19, 2009
4,670
Eastern Ontario
The biggest reason I installed an OAK is
I was upset that the stove used air which I had
paid to heat, for combustion and sent it out the
chimney. Also since I installed the Oak the
room feels warmer with no cold air rushing
across the floor to the stove
 

GrumpyDad

Minister of Fire
Feb 23, 2022
1,094
Champion, PA
My P38 is a basement install (since 2006) with a short 2' OAK. No creosote and very little soot. I do have the OAK insulated or the pipe will get heavily covered in frost during bitter temps. My take is any dealer that claims an OAK is detrimental is lazy and only wants the fast dollar. Install the OAK. BTW - the comment about a cold draft coming down the stairs is valid - I keep my door shut when running the stove.
Interesting read here.
It doesnt surprise me anymore when I see laws or regulations passed based on hunch of 2dimensional thinking.
One thing is certain though, a ton of my make up air is coming from those two windows. As nothing is rarely easy, it sounds like my options are to install an OAK and see if that helps or cover/replace my windows in this area, let the air seep in elsewhere in a less dramatic fashion.
 

GrumpyDad

Minister of Fire
Feb 23, 2022
1,094
Champion, PA
The biggest reason I installed an OAK is
I was upset that the stove used air which I had
paid to heat, for combustion and sent it out the
chimney. Also since I installed the Oak the
room feels warmer with no cold air rushing
across the floor to the stove
yea I think Im going to try it. Worst case I have to cover a little hole on both sides if it doesnt work to my benefit. I am worried about wind fluctuations forcing air through here faster than it would normally consume the necessary air - as my stove was historically a PITA to operate.
 

Ocelot

Burning Hunk
Dec 27, 2010
123
Hudson Valley, NY
I wouldn't want to run a pellet stove without an OAK for big reasons others have stated.

1. The pellet stove has a combustion exhaust fan constantly blowing many CFM of air out the vent pipe. That air has to come from somewhere and without an OAK it would be from the room, creating a negative pressure. A negative pressure sucks outside air in from around windows, doors, and any other opening it can find.

2. The air being drawn from the room without an OAK is already heated air that I paid to heat with the stove.

3. Cold air is denser with more oxygen which aids in combustion. That's why people put cold air intakes on cars.

Ray
 
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VintageGal

Member
Mar 25, 2022
243
NorCal
Dealer said No to me as well, but I met with the installer first and showed him how I wanted it done. I've been running my new CB 1200 insert with and OAK and it was the right decision! No drafts across my floors. I run the stove on low and slow and have to scrape the burn pot every single day but it's worth it to be this warm
 
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tlc1976

Minister of Fire
Oct 7, 2012
1,263
Northwest Lower Michigan
Soot usually comes from the stove not getting enough air. With the OAK the stove can get the air it needs more easily, so there should be the same or less soot with the OAK.
 

Tonyray

Minister of Fire
I wouldn't want to run a pellet stove without an OAK for big reasons others have stated.

1. The pellet stove has a combustion exhaust fan constantly blowing many CFM of air out the vent pipe. That air has to come from somewhere and without an OAK it would be from the room, creating a negative pressure. A negative pressure sucks outside air in from around windows, doors, and any other opening it can find.

2. The air being drawn from the room without an OAK is already heated air that I paid to heat with the stove.

3. Cold air is denser with more oxygen which aids in combustion. That's why people put cold air intakes on cars.

Ray
Spot on!!!!
 

Tonyray

Minister of Fire
9 yrs with a harman P61A and OAK. No signs of soot yet in stove or exhaust pipe outside. No cold drafts pulling back to the stove. Its a no Brainer... Dont get warm air you paid to heat to use for combustion.

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zrock

Minister of Fire
Dec 2, 2017
1,372
bc
yea I think Im going to try it. Worst case I have to cover a little hole on both sides if it doesnt work to my benefit. I am worried about wind fluctuations forcing air through here faster than it would normally consume the necessary air - as my stove was historically a PITA to operate.
my OAK is on the windy side of the house i live in the north so when its windy its frigging windy. My OAK came with a angled cover that bolts over top and stops any direct wind from coming in.. No matter how windy it is the stove runs the same as on a calm day.. Your reading to much into things install a OAK and be done with it, 1000's of people have them installed with no issues they are their for a reason
 
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Tonyray

Minister of Fire
my OAK is on the windy side of the house i live in the north so when its windy its frigging windy. My OAK came with a angled cover that bolts over top and stops any direct wind from coming in.. No matter how windy it is the stove runs the same as on a calm day.. Your reading to much into things install a OAK and be done with it, 1000's of people have them installed with no issues they are their for a reason
agree.. my OAK faces North and we have a huge Lake maybe 300 yrds away with wind comming from it.
never affects the stove flames.. it's that square thing with vents at bottom of rig...

IMG_1841.JPG
 
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Mt Bob

Minister of Fire
Oct 31, 2013
4,422
park county montana
Yep, people seem to forget, the exhaust is on the same side as the OAK. So, as wind tries to speed up in going air, it also is pushing against the exhaust air. I have seen really strong gusts affect my flame,a bit, when on low burn, but only momentary.
 

tlc1976

Minister of Fire
Oct 7, 2012
1,263
Northwest Lower Michigan
With my old pellets that burned pretty weak, the fire would blow out sometimes from the wind. Never had a problem with the current pellets.

I have a dryer vent hood over the end of my OAK. Keeps out rain and direct wind.
 
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doneill127

Member
Feb 10, 2018
15
CT
Think my math is correct, If my stove burns 1.5 to 2 lbs hr, with an air/fuel ratio of 8, the stove is sucking around 3cfm. Living in an 1805 house. With a dry stacked stone foundation and wavy glass windows, not a big problem for me.