Harman accentra - outside air kit not necessary?

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Kyle6286

New Member
Apr 4, 2019
36
New England
Hi All,

I had created a thread last week about issues I'm having with my 1.5 yr old Harman Accentra 52i insert and it not really adequately heating our house, and at least one of the replies on the thread was related to an outside air kit.

If you Google Harman outside air kit, you'll see that Harman highly recommends installing one. However, I just called the company from which I purchased the stove - they also installed it - and the owner said an outside air kit is only necessary for a mobile home, and for the thousands of stove installs they've done over the years, they don't include an outside air kit.

From what I've learned on here regarding outside air kits this past week and how they help create a sealed environment for the stove by using outside air as opposed to using air in the home that has already been heated, recycled, rinse and repeat, it sounds like an OAK would help in my situation, but I was just told it wouldn't.

What gives? I feel as though my stove has a difficult time keeping our house at a comfortable temp of 70 degrees without running on full blast and burning through a ton of pellets, no pun intended, here in New England.
 

fmsm

Minister of Fire
Dec 12, 2011
980
South of Boston MA
Hi All,

I had created a thread last week about issues I'm having with my 1.5 yr old Harman Accentra 52i insert and it not really adequately heating our house, and at least one of the replies on the thread was related to an outside air kit.

If you Google Harman outside air kit, you'll see that Harman highly recommends installing one. However, I just called the company from which I purchased the stove - they also installed it - and the owner said an outside air kit is only necessary for a mobile home, and for the thousands of stove installs they've done over the years, they don't include an outside air kit.

From what I've learned on here regarding outside air kits this past week and how they help create a sealed environment for the stove by using outside air as opposed to using air in the home that has already been heated, recycled, rinse and repeat, it sounds like an OAK would help in my situation, but I was just told it wouldn't.

What gives? I feel as though my stove has a difficult time keeping our house at a comfortable temp of 70 degrees without running on full blast and burning through a ton of pellets, no pun intended, here in New England.
Your stove dealer/installer is lazy!
 

Kyle6286

New Member
Apr 4, 2019
36
New England
I didn't want to come out and say that, but that was my thought as well. Then again, I'm not an expert and I didn't want to call them a liar on the phone.

Although I'm not that handy, I'd say I would give an OAK install a shot myself, but being that I'm dealing with a chimney here, I think I'd be better off having someone who has experience in this sort of thing help with the installation.
 

railfanron

Minister of Fire
Nov 2, 2013
561
Perry MI
Your stove delivers a set amount of BTUs an hour. If the heat loss in your home is more than the stove's output it will never maintain temperature. If you have a house that is not well insulated you're stove may or may not heat it. If it does heat it chances are you're going to use a lot of pellets. If the heat loss of a house is 50,000 BTUs an hour at 35 degrees a pellet insert rated at 50,000 BTUs will heat the room but it will be maxed out. For every degree the temperature goes down the heat loss goes up. Lot's of people buy pellet devices thinking they're going to save lots of money. That's not really the case. If you have a furnace heating you house with gas and it costs 500 dollars a month you can't expect a pellet device to do the job for 200.
The outside air kit will help. If the pellet stove is running it has to get combustion air from inside the house if there is no OAK. This air is then replaced with outside air bleeding in through cracks throughout the house. So basically you using heated air to burn the pellets and replacing it with unheated air from the outside. If your house is very air tight the stove can only draw so much air from the room it's in before the stove's combustion blower can no longer suck the air needed to burn the pellets. This cause a rich burn and low BTU output. So either condition may cause low stove output. By putting in an OAK all combustion air comes from the outside and through the stove. No air from inside the house is used.
Ron
 
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Kyle6286

New Member
Apr 4, 2019
36
New England
Your stove delivers a set amount of BTUs an hour. If the heat loss in your home is more than the stove's output it will never maintain temperature. If you have a house that is not well insulated you're stove may or may not heat it. If it does heat it chances are you're going to use a lot of pellets. If the heat loss of a house is 50,000 BTUs an hour at 35 degrees a pellet insert rated at 50,000 BTUs will heat the room but it will be maxed out. For every degree the temperature goes down the heat loss goes up. Lot's of people buy pellet devices thinking they're going to save lots of money. That's not really the case. If you have a furnace heating you house with gas and it costs 500 dollars a month you can't expect a pellet device to do the job for 200.
The outside air kit will help. If the pellet stove is running it has to get combustion air from inside the house if there is no OAK. This air is then replaced with outside air bleeding in through cracks throughout the house. So basically you using heated air to burn the pellets and replacing it with unheated air from the outside. If your house is very air tight the stove can only draw so much air from the room it's in before the stove's combustion blower can no longer suck the air needed to burn the pellets. This cause a rich burn and low BTU output. So either condition may cause low stove output. By putting in an OAK all combustion air comes from the outside and through the stove. No air from inside the house is used.
Ron

Thank you for your response. This is how I've come to understand an OAK from reading on here. While our house is pretty well insulated, it was built in the 60s so it's nowhere near as good as the newer homes, so I figure adding an OAK will help mitigate the loss of warm air being drawn from inside the house to the stove and cold air then leaking in as you stated.
 

tiger

Feeling the Heat
Feb 3, 2014
401
Seabrook, MD (DC suburbs)
Interesting. I did not know you could have an OAK on an insert. I'd love to have one even if it meant boring a hole (????) through the back of the fireplace, which is brick and I presume very thick.

In our living room, the household thermostat might read quite warm, at eye level plenty of warm air, and along the floor you'd feel a draft of cold air being pulled toward the insert.
 

Kyle6286

New Member
Apr 4, 2019
36
New England
Interesting. I did not know you could have an OAK on an insert. I'd love to have one even if it meant boring a hole (????) through the back of the fireplace, which is brick and I presume very thick.

In our living room, the household thermostat might read quite warm, at eye level plenty of warm air, and along the floor you'd feel a draft of cold air being pulled toward the insert.

This exactly. Unsure of the best way to handle installing an OAK with a fireplace. Also, I too have found your statement about the cold air at floor level to be true.

I'm going to try to call around a few of the local fireplace and stove dealers to see if I can get any helpful info on adding an OAK. Will write back with anything informative.
 

zrock

Minister of Fire
Dec 2, 2017
1,118
bc
yep definitely a lazy dealer... Without running a oak you stove is pulling air from any were it can so every little air gap in your home is going to be sucking air in for the fire...
 

Washed-Up

Minister of Fire
Nov 5, 2011
664
Kananaskis,Alberta, Canada
This may work for you, you’d have to purchase a length long enough for your chimney, or go direct air vent


 
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rickwai

Minister of Fire
Nov 1, 2011
1,189
ohio
This may work for you, you’d have to purchase a length long enough for your chimney, or go direct air vent


That is for a gas installation
 

Washed-Up

Minister of Fire
Nov 5, 2011
664
Kananaskis,Alberta, Canada
Ok the collinear is for gas, had to search that one out... this should be the one I thought would work



 
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rickwai

Minister of Fire
Nov 1, 2011
1,189
ohio
Ok the collinear is for gas, had to search that one out... this should be the one I thought would work



Yeah that is flex liner. But I have not seen a 2 pipe system to go to the top of the chimney with the correct cap ect. Plus a 4" liner with a 3" air flex would be a struggle to get down most chimneys. There may be a system out there, But I have not seen it.
 
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fmsm

Minister of Fire
Dec 12, 2011
980
South of Boston MA
Yeah that is flex liner. But I have not seen a 2 pipe system to go to the top of the chimney with the correct cap ect. Plus a 4" liner with a 3" air flex would be a struggle to get down most chimneys. There may be a system out there, But I have not seen it.
That is exactly how my Harman dealer installed my stove. The prarie cap is what I have and the flexible liner was purchased from the dealer.
 

tbear853

Feeling the Heat
My stove ran the first year or three just fine without OAK.
 

tiger

Feeling the Heat
Feb 3, 2014
401
Seabrook, MD (DC suburbs)
This may work for you, you’d have to purchase a length long enough for your chimney, or go direct air vent

Hmm, I might be a bit skeptical about a set-up where the unit's air intake and exhaust are literally right next to each other. I had some trouble with my gas boiler (Munchkin) and a tech came out -- not the original installer -- and said that, likely, exhaust was getting sucked into the intake (horizontal, not chimney top). He put an extension on one of the two pipes, separating them, and the boiler worked fine after that. Pellet stoves might be different...
 
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Washed-Up

Minister of Fire
Nov 5, 2011
664
Kananaskis,Alberta, Canada
Put an elbow on the intake and make sure the exhaust is higher
 
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zrock

Minister of Fire
Dec 2, 2017
1,118
bc
Not sure how your chimney is layed out and been a while since iv actually looked at one. But i remember my last chimney had a ass clean out on the outside with a cover plate. You could modify your cover plate for a fresh air intake. Also talk to your local heating and cooling as their are lots of options out their as a lot of the new gas systems use 1 pipe for exhaust and intake so they should have something that will work for you... if it were me i would just drill a 2" hole through the chimney and out i go keeping it nice and short..
 
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Kyle6286

New Member
Apr 4, 2019
36
New England
Not sure how your chimney is layed out and been a while since iv actually looked at one. But i remember my last chimney had a ass clean out on the outside with a cover plate. You could modify your cover plate for a fresh air intake. Also talk to your local heating and cooling as their are lots of options out their as a lot of the new gas systems use 1 pipe for exhaust and intake so they should have something that will work for you... if it were me i would just drill a 2" hole through the chimney and out i go keeping it nice and short..

I like this idea only because it seems the easiest provided you have the right tools. It also seems like it would be more effective given the reduced length of pipe. Is it practical to run it all the way up to the chimney, which could be as much as 20 or so feet in my case?

Thanks for the help
 

Washed-Up

Minister of Fire
Nov 5, 2011
664
Kananaskis,Alberta, Canada
That’s the colinear I posted above and may not meet code.
There are direct vent systems out there, but it would be pricey for your length of chimney
 
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mtnbiker727

Burning Hunk
Mar 11, 2019
130
PA
I talked to two different dealers here and they both said they hardly ever install OAK. Of course after the stove was installed I came on here and everyone says you should have one. I don't have any issues, but when we move in the next year or so, the stove is coming with us and I'll install it correctly myself.
 

MapleHill

New Member
Jan 22, 2021
16
Vermont
We operated a 52i last year without an OAK, and this year we have an OAK installed. The difference is night and day as far as burn quality (more active flame) and heat retention. We seem to be burning less pellets as well. The glass stays cleaner, longer. And the drafts are gone. Additionally, it used to take up to 10 minutes to ignite, sometimes longer... now it ignites in 5.

On ours, I took the OAK down through the cleanout and out through a side basement wall. Maybe you could do that too, OP. Not to sound like a broken record, but it's well worth the effort.
 
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gfreek

Minister of Fire
Nov 5, 2010
1,421
Attica,,New York
Without an OAK it's like a exhaust fan running continuously...
 

MapleHill

New Member
Jan 22, 2021
16
Vermont
Yeah, exactly.

The worst part for me was lying in bed last winter after the stove would hit the set temp (automatic mode) and listening to the combustion blower send my warm air outside for 30-45 minutes after the flame went out. All of that heat I just made was going up the chimney and wasn't being offset by the stove running.
 
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fmsm

Minister of Fire
Dec 12, 2011
980
South of Boston MA
We operated a 52i last year without an OAK, and this year we have an OAK installed. The difference is night and day as far as burn quality (more active flame) and heat retention. We seem to be burning less pellets as well. The glass stays cleaner, longer. And the drafts are gone. Additionally, it used to take up to 10 minutes to ignite, sometimes longer... now it ignites in 5.

On ours, I took the OAK down through the cleanout and out through a side basement wall. Maybe you could do that too, OP. Not to sound like a broken record, but it's well worth the effort.
Exactly what I did with one of my inserts, the other goes to the top of the chimney into a Duravent cap called the Prarie Cap. This cap has the hookup for the OA on the base or bottom shelf then a second shelf that the exhaust goes through. The exhaust is lighter than the air so there is no contamination.
 

tlc1976

Minister of Fire
Oct 7, 2012
839
Northwest Lower Michigan
I agree with others. Lazy installer. Do they charge to come back if it happens to not run right too?

Only mobile homes is silly. Lots of newer houses are so airtight that an oak would be necessary. Even my house which was 30 years old when I installed the stove. The flame wouldn’t change with the damper, then after maybe an hour it would choke and die and pull the smoke into the house. When I added the oak it was like night and day, it ran like it was supposed to.