is outside air necessary?

[great balls of fire]

hi everyone,im thinking about installing a pe super27 insert.i noticed in there brochure that u can pull off a plate for outside air .installation is in the basement of a raised ranch.is it beneficial to take that plate off the stove and not put a block off plate on the existing flue so i get outside air that way or dont take the plate off the stove?should the insert have cool air around it or be enclosed with its own warm air?is that code to have that block off plate on? my existing flu plate is 5 1/2 inches would crimping the 6 inch liner thru that opening restrict air flow or would you cut the flue plate?sorry or all the questions i would just like to do this right the 1st time.thanks for the great advice in the past and future. ROB

 

[Ashful]

I'm not familiar with the PE Super 27 (although I'm sure many here are), but it sounds like you're proposing your own coaxial vent. Flue liner up the center, and drawing make-up air down around it thru the chimney chase? Bad idea, as you'll be cooling your flue liner, promoting creosote condensation.

 

[begreen]

This is not a block-off plate. What you are describing is whether to enable the outside air connection or not. If there are competing appliances for the air supply or if the basement has negative pressure, connecting the stove to an outside air supply could help. You will notice air starvation by an anemic fire that gets much better if you open a nearby window or outside door.

 

[great balls of fire]

I UNDERSTAND THAT THE OUTSIDE AIR OUTLET IS NOT A BLOCK OFF PLATE .just wanted to know if it was normal practice to use it in that type application.also wanted to no if the liner going thru the existing fireplace flue needs a kit or does go thru with no insulation around it .and is your
liner insulated all the way up your chimney ? thanks joful for the advice you think it will cool the liner even if it was insulated all the way up the stack?

 

[Ashful]

I think we're using a few different terms here, and I'm not familiar with the PE Super 27, although I'm sure some member who is will come along eventually. In the mean time, to answer your original question, outside air is not normally necessary. It is only necessary if your house is too tight to supply the required make-up air for the stove, or if you have too many air-drawing appliances (radon fans, dryers, range hoods, etc.) competing with the stove for air, and your house's leakage cannot keep up. The standard advice, in all cases excepting where it will be later impossible to add, is to install the stove without the outside air kit, and see how it works. If your stove is sluggish with the windows closed, but opening a window makes it work much better, then it's time to add the outside air kit.

As begreen suggested, that outside air cover plate is to remain in place, unless you're installing an outside air kit. Usually, outside air is not drawn down thru the chimney, but one of our pro installers can tell you more on that.

Insulating the chimney liner is always a good thing, but is often not necessary. That will depend on your existing chimney construction, so please tell us more about that.

 

[clemsonfor]

not sure of your stove but some may require OAK but not sure if it does. No you don't want to pull off your block off plate or damper to allow air to be pulled from above the chimney. And you do want to pull the block off plate so that it is not restricted to being squeezed thru a 5.5" opening. the 6" liner is really like 6.5''s outside diameter. The stove in its own warm air will allow you to get more heat as your not loseing heat and its staying warm and not creosoting.

 

[PA Fire Bug]

I would strongly recommend installing an outside air source if it is not too much trouble to run the vent to the outside. It made a big difference with our Super 27. Cold starts are much easier even when the chimney is cold. When I to start basement Super 27, without outside air, I have to burn some newspaper in the chimney cleanout to avoid filling the basement with smoke. I posted pictures of my installation at https://www.hearth.com/talk/threads/outside-air-intake-installation.89653/#post-1168561 . I wish that I would've installed the outside air vent before laying the tile. : )

 

[Umaxman]

I have the OAK installed on my PE 27 but I never ran it without one so I can't say if it made any difference......

 

[great balls of fire]

the existing chimney is in decent condition. unfortunetly i would have to chop out block and then brick to get the outside air in to my home. it seems like an awful a lot off work for something u may not need.thanks for the heads up everyone.

 

[clemsonfor]

If your not going to run it outside and its a required air inlet I would at least run it to your living space and not have it pull from behind the insert. Or better yet run it as far as you can from the insert then terminate it. You only have to have them legally I think if the install says you have to have it or if your in a trailer, mobile or modular home..whatever you want to call them. Or if your current house is really really air tight.

 

[great balls of fire]

its not required but it is there if needed. i was thinking of pulling the air behind the insert but someone on this thread said it would be a bad idea pulling air thru the chimney stack past your liner promoting creosote condensation

 

[Ashful]

Yes... basic idea is you want to keep your flue or liner warm. Anything that promotes cooling of the liner promotes creosote accumulation.

In your case, unless you know your house to be exceptionally tight, I'd be installing the stove without an outside air kit. Since it sounds like a pretty big job to get to the outside, given your setup, I'd want to be sure I wasn't doing it unless necessary.

 

[great balls of fire]

my home is almost 40 years old.I doubt its tight i will take my chances without it.i have a pellet stove upstairs without a OAK and its toasty upstairs.I wasnt sure if you needed them with wood inserts, thanks

 

[Ponderosa Pyro]

my home is almost 40 years old.I doubt its tight i will take my chances without it.i have a pellet stove upstairs without a OAK and its toasty upstairs.I wasnt sure if you needed them with wood inserts, thanks

If you want to pull cold air into your house around every leaky door and window then go ahead.I will never have a wood stove without outside air after having one with.I would personally do whatever it takes to hook up your outside air to an appropriate source.

 

[great balls of fire]

this may sound stupid but has anybody ever ran there outside air along there insulated liner up the chimney flue if
the flue is large enough .and what height is normal for an outside air for a wood insert?

 

[turbocruiser]

this may sound stupid but has anybody ever ran there outside air along there insulated liner up the chimney flue if
the flue is large enough .and what height is normal for an outside air for a wood insert?

If anybody ever ran their OAK along their insulated liner I have not heard about that but the main thoughts I have are:

1. The OAK tubing itself would have to be totally noncombustible. I'm not sure what PE's OAKs are?
2. The chimney tubing itself would have to be totally unsurrounded by support boxes, support braces, attic shields, insulation shields or framing that is too close to fit for both the chimney and the OAK tubing, etc. I'm pretty sure that something is surrounding the chimney there right?
3. Depending on where the OAK would finally exit from the house, it would have to still be far enough from the chimney cap to prevent the output of the chimney changing.
4. Depending on where the OAK would finally exit from the house, and therefore the total length of the tubing, it might make for some suction restriction where the stove would still take some air from any leaks in the house.
5. Depending on how you routed it, it might look really weird.

It's definitely thinking outside the box but I guess what I would like to learn is why this would be advantageous in your specific situation?

 

[Ashful]

If your inlet is at the same height as your outlet in a sealed system, how do you expect to achieve any stack effect? Won't the draft always be completely stalled? How will the smoke know to use the chimney for exhaust, and not the OAK?

 

[clemsonfor]

How thick is the brick/block?? A rental electric chisel/hammer should bust through it in 15-20 mins max then you can cram the tube through the back of the firebox and then grout or silicole the rough opening back up.

 

[great balls of fire]

The only reason i came up with running the OAK up the chimney flue was because its a lot easier dropping 3'' pipe down a hole rather than busting thru a fire box and than coring a hole thru brick.after running the OAK off the stove it would have to rise up at least 8' up above the stove to be a foot above grade out the back of the chimney. I also have a bad feeling that there might be steel behind the firebox block.just a hunch.And to answer Joful the liner would have to be higher out of the chimney then the OAK.Theres no problem busting out the firebox block its whats behind the box. Thats my concern.Is it normal to have steel behind these fireboxes?thanks for the input everyone.

Rob

 

[evilgriff]

I have a leaky house and after dealing with the stack effect over the winter I am considering an OAK on my stove. I know it won't cure the stack effect issue with the internal heat in the house, as that is also a huge issue, but I am sure it would help somewhat. Not sure where in the time frame this is going to occur. In your case, it's the degree of difficulty--If it is not that difficult to do, I can't see any reason not to. If I had a very nice house and were doing everything the right way, I believe an OAK is the right way. Bite the bullet and be done with it.

 

[semipro]

this may sound stupid but has anybody ever ran there outside air along there insulated liner up the chimney flue if the flue is large enough ...?

Sort of. We used to have a direct vent gas stove on our hearth. The air intake and exhaust pipes ran co-linearly up the flue to the top. It worked great.