Outside air for Defiant Encore

[BillSpohn]

first time on the forum...

I have a VC defiant encore (with catalyst) vintage 1989, it is installed on the first floor in a big living room (great room)
Presently, the combustion air is pulled from the room, or we occasionally open a nearby window
both arrangements tend to be drafty to very drafty

the wall behind the stove is a brick "false wall" with a 3" (or so) airspace between the brick and the wall board behind it
there are 26 openings at the top and bottom of the wall for air circulation, each opening is 1/2" x 4"
that wall is an outside wall

I was thinking of my own fresh air kit - putting an opening in that wall to bring in outside air for combustion.
I figure it would deliver the air to the warmest part of the room, distribute it thru the openings and reduce the drafty feeling we currently have

can anyone imagine the problems I might encounter?
condensation inside the wall space?
the need to out a "check valve" to limit airflow out when the wood burner is not going?
pests getting in the vent? (put a screen over it)
will the air cool the brick which serves as a sort of radiator, too?

thanks in advance!

 

[Gooserider]

I split this thread off since it seemed significantly different from the earlier messages.

Yes you can put an outside air kit (OAK)on an Encore, or you could do as you were thinking and just put an opening in the wall behind the stove. I think you would be better off to use the regular kit though, as it is likely that putting a hole in the wall would still cause significant draft problems. I haven't actually seen the kit for the Encore, but my understanding is that it basically just replaces that stainless plate that currently covers the primary and secondary air inlets with a similar plate that has a nozzle on it, such that you can hook up the nozzle to the OAK plumbing. I would probably remove one brick from your false wall in order to make a gap for the OAK inlet to come through. This would minimize or avoid most of the problems you mention being concerned about.

Gooserider

 

[elkimmeg]

If the stove running can pull draft threw the wall the my first suggestion would to button up the areas you feel the draft Really with the tiny slits for air in a stove then closing them down
not all that much air is needed for combustion. . OAK might eleviate some of the pull of cold air in but that will be a minor difference the real problem lise elsewhere draft stopping

 

[swestall]

It is unclear what problem you are trying to solve. The CAT Encore will produce tremendous heat the way it is, so unless you are looking to solve another problem, why bother? Circulating the heat is also another question. Which are you seeking to do?

 

[JimWalshin845]

If I weere to add an OAK I would pipe it from the basement. No drafts from winds and the temps would be 50ish rather than 30's or below.

 

[kwburn]

anyone have a part # for the outside air kit and is it still available?

 

[JimWalshin845]

anyone have a part # for the outside air kit and is it still available?

Try this:

(broken link removed to http://www.vermontcastings.com/catalog/elements/files/2007/2000956_Encore_2550.pdf)

or look at their site:

http://www.vermontcastings.com

 

[kwburn]

my defiant is a 2190. looked around a bit and there appears to be kits for every stove although i didn't find my exact one. it looks like most are around $80 though so not sure its worth the trouble or cost.

 

[JimWalshin845]

(broken link removed to http://www.vermontcastings.com/catalog/elements/files/Definat%20Encore_2190.pdf)

(broken link removed to http://www.vermontcastings.com/catalog/elements/files/2007/2004042_Outside_Air_Encore.pdf)

 

[kwburn]

i confirmed it's available for the 2190. $80.
i could get it and run an air line down the cleanout into the basement but i really don't know if it justifies $80.

 

[Gooserider]

From your description I'd say that your first effort should be put into going around and stopping up as many of your draft openings as you can - weather sealing is almost always your best payback investment for improving heating efficiency and increasing your comfort.

If you find that you've managed to do such a good job of draft sealing that the combustion of the stove is hurting (not likely) then I'd worry about putting in the OAK.

Gooserider

 

[BillSpohn]

thanks for all the feedback!

I work in combustion engineering... so I differ on the point that I just need to seal up the drafts,
the air has to come from somewhere for the wood to burn, I just want to control where it enters the house
if I pipe the OAK to the basements, it will de-pressurize the basement, maybe reversing the draft on the waterheater and spilling flue gas, Carbon monoxide, etc., not good.

from (broken link removed)
AIR-TO-FUEL-RATIO -- The ratio of air and fuel, by weight, in a solid fuel appliance. It should be noted that 1 pound of dry air occupies a volume of 13.315 cubic feet at 70 degrees F. Therefore, 35 pounds of air, the typical amount of air necessary to burn 1 pound of wood in a fireplace, occupies 466 cubic feet.
So if I load up with 30 lbs of wood for a 6 hour burn, I will need 40 CFM of air entering the house while burning.

Once I get it back together, I will take some pressure tests and report back
(I work for an HVAC test instrument manufacturer and have access to all kinds of great toys - uh, I mean tools!)
(I posted in another area that I need a replacement lower fireback - hard to believe mine is warped - see the photos on the other posting I made tonight)

 

[webbie]

PA. you will find a lot of info on this stuff, but a lot of "experts" have found the OSA lowers the combustion temps inside the stove and often more than offsets the savings from that air NOT being pulled into your room from cracks, etc.

Of course, if your house is tight, that may be another story. Still, an air to air heat exchanger may even work best in that case.

 

[BillSpohn]

thanks, good point
Happy thanksgiving to all of you!

 

[JimWalshin845]

thanks for all the feedback!

I work in combustion engineering... so I differ on the point that I just need to seal up the drafts,
the air has to come from somewhere for the wood to burn, I just want to control where it enters the house
if I pipe the OAK to the basements, it will de-pressurize the basement, maybe reversing the draft on the waterheater and spilling flue gas, Carbon monoxide, etc., not good.

Since they are already drawing air from the inside of the home, aren't they already depressurizing the basement too? I could see if the house was air tight and they were able to heat it with a candle, but this doesn't seem the case. Shouldn't the draft regulator compensate for the 'depressurization'?

I could see it possibly happening if there was a fan unit on it, but being gravity fed, IMHO, should not dramatically change anything and avoid another hole in the wall to allow more cold into the home!

Anyone else have any ideas here?
Jim