Outside Air Question

[Big D.]

I have a Harman P61a, and I have a question. I have a spare chimney flue that is not in use. I am thinkihg about hooking up to it for outside air. Would the draft of the chimney be too much for this to work? Thanks.

 

[fmsm]

I have a Harman P61a, and I have a question. I have a spare chimney flue that is not in use. I am thinkihg about hooking up to it for outside air. Would the draft of the chimney be too much for this to work? Thanks.

Run a pipe to the top of it.

 

[Big D.]

fmsn, Thanks for responding. This is for fresh air only, not venting. Is the thought that running a smaller pipe up the flue wpuld decrease the amount of draft?

 

[Ssyko]

The only way you will get draft is if warm room air can go up the flue. If you run your oak up and seal the bottom off you shouldn’t get any draft, providing there is no other appliance attached to the flue which would be a no no.

 

[Big D.]

Makes sense.

 

[bcb1]

Lots of discussion in years past on the need for the cold air pipe hookup. Some guys swear by it, some say completely unnecessary.

I’ve ran a pellet stove for years, since 2005. First a Quad and now a Harman. I’ve never had the fresh air hookup on either stove. The installer in both cases told me there was plenty of air in the house, no need for outside air. In 15 years, no problems from not having the fresh air hookup done.

Maybe the latest and greatest advice has changed....? I’d definitely ask your dealer but mine just sort of shrugged and said well if you really want it we can do it.....

 

[Tonyray]

I used to get a real cold draft running along our floors that was the air going back through the stove. That stopped when I had an oak installed.

 

[Ssyko]

He’s adding the OAK, just verifying if it would be an issue to use an extra flue he had available.

 

[Big D.]

Thanks for the responses, I have run my stove for two years without outside air. No problem. I thought if I could hook it up easy enough I would give it a try and see If it made any difference. My stove is kind of in the middle of the room. Having the spare flue I thought it might be easy to hook up outside air. Not sure why if I can make a good seal where the pipe enters the flue I would need to pipe it up to the top. My dealer is kind of like one of those guys that says nah I don't bother with those things. So I thought I would ask on here and see what people smarter than me had to say.

 

[Pete Zahria]

I have run my stove for two years without outside air. No problem.

I don't think many would say you will have a 'problem', per se, the problem is,
if you ever stick your hand over the exhaust outside, that rush of air
that you feel, is being replaced with cold air from outdoors.
If it's 0° outside, that is what is trying to get
inside, to keep you fire going.. and it does.
So without OAK, you are using air that you have heated,
for combustion. If you have a super efficient house,
you may not get enough air to satisfy the demand..
But that is everyone's own choice/opinion...
I use one on both my stoves.

Dan
(and I do not claim to be smart.. )

 

[Tonyray]

Agree. Especially drawing air back to the stove that you paid to heat.

 

[Big D.]

My question was about using a chimney flue

 

[Pete Zahria]

And my response was about running without an outside air intake...

Dan

 

[Talegas]

My question was about using a chimney flue

Hehehe... it always, for whatever reason, comes to a discussion about OAK good vs. OAK bad.

In your case, you want to use the extra flue to pull cold air from outside into the burning chamber of your stove. Just like the exhaust system, you have to take into consideration how hard will be for the stove to pull air from wherever you are pulling it from.

I have one of those fireplaces that have a small door to dump the ash to the basement, so i leave that open, close the fireplace glass "window" and let the stove draw cold air from the cleanout door down in the basement (the damper is closed). It is working. .. is it efficiently doing so? doubt it since the exhaust blowing fan is working harder to pull air from an "enclosed" albeit drafty place, and on top of that push air up the long Class A chimney is hooked up to.

So in your case, i will assume you will "seal" the OAK and the flue, otherwise you will have a something like leaving the window open situation.. too much heat coming up that flue .. if you dont seal it. .the stove will still be able to draw air from it. .maybe not entirely cold air from outside.

Can it be done? will your stove work? i bet it will.. ..is it the most efficient way to get an OAK ? dunno. you can always increase the exhaust fan voltage if it cannot push that much air as it is.

 

[Big D.]

Yes, was planning on sealing well. figured it was worth a try if it doesn`t work well I will go back to no OAK.
Thanks

 

[Talegas]

Yes, was planning on sealing well. figured it was worth a try if it doesn`t work well I will go back to no OAK.
Thanks

only way i think you'll be able to tell if is struggling or not.. is with something to measure air flow.

now on the extreme end of the situation, your flame will be lazy as not enough air would be circulating. . or more ash will be generated as no clean burning.. stuff like that.

 

[Big D.]

agreed. I figure if I notice flame deviation from how it burns now it is easy enough to disconnect

 

[SidecarFlip]

I don't think many would say you will have a 'problem', per se, the problem is,
if you ever stick your hand over the exhaust outside, that rush of air
that you feel, is being replaced with cold air from outdoors.
If it's 0° outside, that is what is trying to get
inside, to keep you fire going.. and it does.
So without OAK, you are using air that you have heated,
for combustion. If you have a super efficient house,
you may not get enough air to satisfy the demand..
But that is everyone's own choice/opinion...
I use one on both my stoves.

Dan
(and I do not claim to be smart.. )

Exactly. Why use already heated air for combustion, makes no sense to me. Over the years, been my observation (at least) that the cold ambient outside air provides a better burn. Could be my imagination however.