# Air intake from outside or not?



## jimcooncat (Nov 19, 2008)

When my installer put in my Napoleon NPS-40, he said I didn't need the air intake piped to outside the house. Now that it's getting chillier and I've used it some, I wonder if it's the right move. 

Intake from within the house seemed smart to me -- the fire is burning with 68 degree air. I'm now pumping air from inside to outside the house. That inside air must be replaced to even the air pressure. So now the pressure outside the house is greater than inside, forcing cold air in through any leaks I have. As I'm buttoning up the house more, I can imagine that whenever I open the door a blast of cold air is going to be sucked in. 

With an intake from outside, the fire will be burning with zero degree air. But there won't be any pressure difference inside and outside the house, and would reduce infiltration.

What do you think?


----------



## cac4 (Nov 19, 2008)

The temperature of the combustion air is not a significant factor.  If anything, the fire will burn hotter with colder air, because cold air has a higher concentration of O2.  

consider the 68 degree combustion air: you paid money to get that air to 68 degrees; now, you're sucking it out of the house at a high rate.


----------



## Xena (Nov 19, 2008)

Added outside air last month after running
a few years without it.    In the living room
where the stove is located, there was always 
a cold draft at floor level due to the stove
sucking up the inside air.  My feet would even
sometimes feel cold.  Thing of the past now.
If I ever install another stove I will set it up
using outside air from the start.


----------



## jimcooncat (Nov 19, 2008)

You guys just plain rock. I stopped by my stove guy's place today (Monitor of Maine in Benton, tell 'em Jim Como sent ya) but he just said, "Yeah, it would burn more efficiently."

But you really answered this well, so my girlfriend and I could understand it. "It's sucking the heat right out of our house!" Smart. She's had cold feet too. We bought an electric mattress pad set last week -- I highly recommend 'em.

I didn't know that colder air had more oxygen. My fire needs all it can get! Maybe we can stay with every-other-day cleaning instead of having a clunker in the pan on the second morning.


----------



## sydney1963 (Nov 20, 2008)

OAK highly recommended.


----------



## peirhead (Nov 20, 2008)

Check your owner's manuel as a lot of stoves do not use the outside air for combustion but as supply to the circulation blower/heat exchanger...so the idea is you are burning stale room air @68 deg F and replacing it with fresh heated air...

If you have a balanced type air exchange system any make up air will be supplied through it and an OAK install would not be necessary at all.


----------



## trogers (Nov 20, 2008)

I had  astove installed in September with no OAK...big mistake.  Flame was always lazy, never big like the showroom.  I installed OAK and eveything is better now!


----------



## pelletfan (Nov 20, 2008)

I want just to add my 2cents in favor of an outside air intake too.
On the beginning I thought like so many other stove users that I would not need one. 
Big mistake.
Our home is very nice insulated etc. etc. so quite energy efficient one could call it.
When using my pellet-stove, I noticed that my two bathrooms which are on the same level than the Pellet Stove were cold like refrigerators.
It did not matter,  if I left the door open or closed. Everyone in my family complained. 
When looking into the matter I noticed that the stove was drawing cold air from the bathroom through the exhaust fans (least resistance).
After installing air flaps on the exhaust fans and an air intake for the stove, the temperature in the bathrooms turned to normal again.
Just never thought that the stove would be able to draw that much air through the exhaust fans.


----------



## cac4 (Nov 20, 2008)

pelletfan said:
			
		

> Just never thought that the stove would be able to draw that much air through the exhaust fans.



my forced hot air furnace is in the basement, and uses indoor air for combustion.  The wife often leaves the basement door open, so that she can hear the clothes dryer "buzz" when its finished a load.  When the furnace kicks on, that door will close all by itself, with "authority".  The knob latches with a firm "ca-THUNK".


----------



## Lance1 (Nov 20, 2008)

Sorry for the newbie question; What does OAK stand for?


----------



## j00fek (Nov 20, 2008)

once i get my stove in the right spot, ill be adding the OAK. but since my house is like a screen poarch, ill wait till the house is finished next yr.


----------



## cac4 (Nov 20, 2008)

Lance1 said:
			
		

> Sorry for the newbie question; What does OAK stand for?



"outside air kit".

so the stove can suck in its combustion air from the outside of the house.


----------



## Lance1 (Nov 20, 2008)

Thank you. There are kits?

My stove combustion intake is inside. I would like to put it outside, but I have a corner installed insert and would have to cut a person size hole in the wall to get to it. (bought a house with the stove already installed)


----------



## bungalobob (Nov 20, 2008)

Lance1 said:
			
		

> Thank you. There are kits?
> 
> My stove combustion intake is inside. I would like to put it outside, but I have a corner installed insert and would have to cut a person size hole in the wall to get to it. (bought a house with the stove already installed)


If your stove allows it, there are kits. I was at the stove shop the other day planning the install and they showed the small 'birdcage box' and flex stainless pipe that would hook up to it. The piping is small, between, I think between 2 1/2 to 3 inches.
You should be able to move your stove out and get behind it. No need for a person size hole. If you have a wood frame house all you need is a hole saw and silicone. Look up your stove and see if it can take an OAK. Good luck.


----------



## MrKLeen (Nov 20, 2008)

I have the same stove as you, see my post from a different thread...

https://www.hearth.com/econtent/index.php/forums/viewthread/28593/

By the way, the intake on the stove is 2 inches, I simply cut the flex pipe in 4 places and foil taped it on, then insulated around the pipe. It works great and does not leak. This is how my dealer said to do it.


----------



## slls (Nov 20, 2008)

bungalobob said:
			
		

> Lance1 said:
> 
> 
> 
> ...



I bought a 2 1/2 hole saw for mine, 1 hole in and 1 hole out with some silicone to seal.
Bought 2 inch aluminum pipe and made the rest.


----------



## Lance1 (Nov 21, 2008)

I found the OAK at the hardware store, it was $50  I went to the auto parts store and got 1.75" aluminum flex tubing for $6. I found out my fireplace insert had a fresh air channel in it and is hooked up to the outside, so I tapped onto that. 

There is no way I can set a pipe to the outside without cutting a person size hole in the wall. My stove is a corner install with walls.


----------



## jimcooncat (Nov 22, 2008)

** UPDATE **
Installed the OAK this afternoon. It was 60 bucks in the pellet shop, and all it consisted of was a 2" metal hose, an outdoor hood, and a hose clamp. Not even a wall thimble included -- yeah, I know it was a rip. She said, "buy it." So what's a boy to do?

Man, it was rough outside. After sawing the hole from the inside, I put on my zoot suit and got the outside drilled. Then I put the hose through from the outside, went back in, and saw how much I had extra. I marked it with a felt pen, then pushed it back outside a ways and put the end over my intake. That held it good while I hacksawed through it. I discarded the end, and pulled it back through the wall to clamp it to the intake. Then I went back out and screwed the hood into place. Back inside, I sealed around it with aluminum tape. 

While the stove was down, my oil furnace clicked on. I've got it set at sixty on an electronic thermostat. If we ever bump up the heat, it will reset back to sixty degrees at the next four-hour mark. 

I cleaned it good and fired that puppy up. It's working like it's supposed to now! No cold draft is building up around it, and the room is warming nicely. It went from 62 to 66 in about an hour and a half, and I believe it will top out at 72 or so. With the Arctic Blast going on outside today, I'm finally impressed by it. The floor in front of the stove is warm enough to lay down on the rug.

Unless you're installing in a small showroom like my pellet guy, an OAK is not an optional item. It's a necessity. Wished I had known that when the installers were here!


----------



## bungalobob (Nov 22, 2008)

jimcooncat said:
			
		

> ** UPDATE **
> Installed the OAK this afternoon. It was 60 bucks in the pellet shop, and all it consisted of was a 2" metal hose, an outdoor hood, and a hose clamp. Not even a wall thimble included -- yeah, I know it was a rip. She said, "buy it." So what's a boy to do?
> 
> Man, it was rough outside. After sawing the hole from the inside, I put on my zoot suit and got the outside drilled. Then I put the hose through from the outside, went back in, and saw how much I had extra. I marked it with a felt pen, then pushed it back outside a ways and put the end over my intake. That held it good while I hacksawed through it. I discarded the end, and pulled it back through the wall to clamp it to the intake. Then I went back out and screwed the hood into place. Back inside, I sealed around it with aluminum tape.
> ...



Forget about the price and just enjoy the results. Congrats, too bad the furnace kicked on though.


----------



## drizler (Nov 23, 2008)

If you have a standard sized inlet pipe you can just make one.   For mine all I did was go to Lowes and buy a piece of Aluminum flexible dryer hose.   The only hard part was drilling the 3 inch hole in the wall.    Luckily I knew a guy who had a hole saw so I bummed his.   I used an extra roof vent flashing disk to dress up the inside and just slid it in place and stuffed the dryer vent out the hole .   For a cap I used a simple aluminum 3" B vent gas cap.   It even looks good and the whole rig with a clamp cost me under $15.     Using that hole saw made a hard job easy in so many ways by limiting penetration as I desired it so there were no surprises in the form of cut wires back in the wall.  Also it keeps from splitting plastic siding in the cold as long as you are careful.   I used a hair dryer to heat up the plastic siding as further insurance against splitting.


----------



## Jester (Nov 23, 2008)

Ok
Ive been looking at this for the last few days.  Ive got such a draft coming up from the basement and around every door and window on the first floor its insane. (up until this Fall I had no insulation in the house anywhere.  Was burning a 275 of oil every 16-18 days keping the house at 68)

My instalation is in the middle of the living/dining room on the street side of my cape. I think to alleviate the cold air being sucked in every crevice Im going to do the OAK
I'd like to keep it decent looking, and am even going to go so far as to paint it black.
Who makes a decent OAK with an internal wall thimble?
Thanks
E


----------



## Xena (Nov 23, 2008)

Jester, I used automotive exhaust flex pipe
adapted into 3" flex dryer vent then went
into a dryer vent kit.  I used a 2" to 3" coupler
I found at the hardware store to join the pipes.
It looks fine on the outside.   

Post #15 in this thread has pictures of the finished set up.
https://www.hearth.com/econtent/index.php/forums/viewthread/25479/
Here's the same dryer vent I used: 
http://www.amazon.com/dp/B00171RQEO?smid=A9HNR4I8RXLVW&tag=dealt28673-20&linkCode=asn


----------



## suzannegale (Nov 23, 2008)

I have a question about whether an OAK is needed with my install or not. My Englander is in the basement, which is very large (runs the entire length of the house). The guys who installed the stove said the OAK wasn't needed because the basement isn't insulated and it's large enough to have plenty of cold air. They also said it wasn't required by code with the dimensions on the basement. They were very particular about sticking to code on everything else, so I'm inclined to believe them.

Guess I'll have to wait it out and see how the stove performs - I hope to not have to install an OAK because the stove is installed on the interior wall of my 2 family house and windows are across the room.


----------



## Xena (Nov 23, 2008)

coldinnh said:
			
		

> I have a question about
> whether an OAK is needed with my install or not. They were very particular
> about sticking to code on everything else, so I'm inclined to believe them......



I believe all Englander Stoves require outside air.  
Check your stove manual.


----------



## suzannegale (Nov 23, 2008)

Hi Zeta,

The manual did say they require OAK, so . . . even if it's not required for city code, it will be required for warranty/service from Englander. I'll look into getting an OAK kit. Thanks for the quick response! I think the installers were talking from a point of practicality - they said OAK is more of a necessity for smaller, airtight houses and mobile homes. My huge basement, draft New Englander home didn't set off any of their fireman flags which don't necessarily have anything to do with unit spec. I did like that my installers were all firemen - they have this other business on the side.


----------



## Xena (Nov 23, 2008)

Your town inspectors go by the stove manual.
If the manual says it's required, then
it's required in order to pass inspection
afaik.   I'm no expert by any means, I'm
just repeating what I've learned here.
Good luck with it.

edit:  I would like to add that I exchanged pm's
with Mike from ESW about outside air kits and
he specifically told me *not* to allow my stove to
draw air from the basement.  You may want to send
him a pm to discuss this in depth.  Again, much luck
with your new stove.


----------



## taperk600 (Nov 23, 2008)

Just a question...... I see most of you have stoves. I have a boiler. I'm going to guess that the same issues arise with the boilers as with the stoves. If so, the same benefits should be gained from adding the OAK ?


----------



## jimcooncat (Nov 23, 2008)

Well, if you're pumping air from your cellar, through the firebox, and out the exhaust, you're creating a mild vaccuum inside the house. The pressure of the cold air outside the house will force air inside to make up for it. 

With an OAK, you're pumping air from outside, though the firebox, then exhausting it back outside. Pressure stays even. Wind will still force cold air in through the cracks, but you're not actively sucking it into the house.

So sure, a boiler will have the same issues. What gets confusing with a hot air system (most pellet stoves) is that there are two air streams, one for combustion, and one to distribute heat through the house.

The OAK cut down on the drafts immensely. I'm seeing this morning that the amount of BTU's my stove's putting out isn't going to keep up with the cold north wind of last night. Even so, it's more comfortable even at a lower overall temperature. And it's better in that I think I'll be able to pinpoint the problems in my house now that I don't have the artificial pressure differences going on.

So now I'm going back to insulating my cellar, and the other yearly buttoning-up activities I normally do at the start of winter. I'm resigning myself to a one-time click of the oil furnace in the morning, and working it out so the pellet stove will keep up with the rest of the day. Maybe next year I'll be able to replace the oil furnace with a wood stove, and possibly a pellet basket for it.


----------



## Drivr (Nov 23, 2008)

coldinnh said:
			
		

> I have a question about whether an OAK is needed with my install or not. My Englander is in the basement, which is very large (runs the entire length of the house). The guys who installed the stove said the OAK wasn't needed because the basement isn't insulated and it's large enough to have plenty of cold air. They also said it wasn't required by code with the dimensions on the basement. They were very particular about sticking to code on everything else, so I'm inclined to believe them.
> 
> Guess I'll have to wait it out and see how the stove performs - I hope to not have to install an OAK because the stove is installed on the interior wall of my 2 family house and windows are across the room.



the thing is your stove probably will work fine but you will be sucking air from inside your home and sending it out your stoves chimney. Most people forget there are 2 different blowers in these things, one circulates the air through the heat exchangers and the other is used to feed the fire.  this is the same air you are heating with your pellet stove. so you are heating the air in your basement then turning around and sending it right back our your chimney. on top of that it is also creating a negative atmosphere in  your home so it will be pulling in outside air from anywhere it can, around doors, windows, stove, vents, chimneys etc. 
I tried what you are doing and finally broke down and installed the OAK and man what a difference it made.


----------



## wjlundyjr (Nov 23, 2008)

My basement corn stove flat out would not run, until I added OAK.  I would get a healthy blaze going and come back a few minutes latter and it would be fizzeled out.  Added the OA and the things goes like a blow torch, my OA has a ball valve so I can turn down the air supply.

My new wood stove on the upper level (Ithought for sure I'd need OA) can go like an inferno 24*7 with no OA and is easily controlable with the stoves air controls..  But I do leave the stoves door open awhil until a hot draft is going.


----------



## pt0872 (Nov 23, 2008)

My OAK isnt installed....thinking I'm going to do that this week after reading this.

I put my hand over the intake on the stove and couldnt really feel air being pulled in. Should I 
be able to feel the air being sucked in or is it very subtle?


----------



## wilbilt (Nov 23, 2008)

I have been on the fence about installing an OAK.
My stove uses a single fan, which means a single source for both combustion and heat exchanger air.

If I connect it to the outside, it may burn better and reduce drafts, but then I will be continuously attempting to heat the freezing air from outside instead of the preheated inside air.

BTW, it is a mobile home, but nowhere near airtight. In addition to all of the drafts around the windows and doors, there is an OAK installed at the furnace blower with an automatic damper to allow fresh air replacement.


----------



## Xena (Nov 23, 2008)

wilbilt said:
			
		

> If I connect it to the outside, it may burn better and reduce drafts,
> but then I will be continuously attempting to heat the freezing air
> from outside instead of the preheated inside air.



That is the idea. The stove is better off using the colder air to run..



			
				wilbilt said:
			
		

> I have been on the fence
> about installing an OAK. BTW, it is a mobile home...




Please check your stove installation manual, I'm pretty sure outside air
is required for all pellet stove mobile home installations.


----------



## wilbilt (Nov 23, 2008)

zeta said:
			
		

> That is the idea. The stove is better off using the colder air to run..



Yes, better to burn, but how about the loss in heating efficiency when it is pushing freezing air through the heat exchanger instead of warm inside air?



			
				zeta said:
			
		

> Please check your stove installation manual, I'm pretty sure outside air
> is required for all pellet stove mobile home installations.



I would love to find an installation manual. The company that built these stoves has been out of business for a long time.

It does state that outside air is required for MH installations under the hopper lid. I don't know how the original OAK would have been configured, but I think I can fabricate one pretty easily.

Like I stated, I have been thinking about it, but I don't want to do it if it means I will be burning twice as much fuel to heat my home.


----------



## Xena (Nov 23, 2008)

wilbilt said:
			
		

> .....how about the loss in heating
> efficiency when it is pushing freezing air through the
> heat exchanger instead of warm inside air?



It doesn't push freezing air through the heat exchangers.

https://www.hearth.com/econtent/index.php/wiki/burning_pellets_for_newbees


----------



## wilbilt (Nov 23, 2008)

zeta said:
			
		

> wilbilt said:
> 
> 
> 
> ...



This one does. Air enters the rear of the pedestal base, and there is a single fan that pressurizes the interior of the stove and pushes air through both the firebox and the heat exchanger tubes.

If I add an outside air tube to the intake, that air will supply both the fire and the room.


----------



## please302 (Dec 8, 2008)

I too was interested in the outside air kit. I thought that it would be more efficient and wouldn't act as a fireplace by sucking in the cold outside air. I just had the pellet stove installed and the dealer stated that it was not as efficient as all the hype. Actually, due to hot air rising and cold air falling and pressure inside your house you actually need air movement. As hot air rises you need it to force cold air down and back to the stove to circulate the hot air in rooms where it is cold. The "wall" of cold air is difficult to displace if you do not have flow thru the house and that is why it is so important when you decide where to place your stove. I think that it really depends on your house's layout, efficiency and the placement and heat output of your stove.


----------



## peirhead (Dec 8, 2008)

I think I misread the Quad Castile owners manual as I thought the outside air kit for it provided air to the convection blowers but on careful review it may be on the combustion side...has anybody ever heard of a pellet stove using outside air for the convection blower?

I know there were woodstoves in the early 80s that worked this way. (Heatilator Pressurizer for one)


----------



## Scoop (Dec 8, 2008)

cac4 said:
			
		

> pelletfan said:
> 
> 
> 
> ...



You shoud vent the furnace room. Not good that the furnace is creating that much of a negative pressure to close the door. Likely means your furnace is gasping for air with the door closed. Just install a return air wall  plate somewhere in the furnace room wall close to the floor so it sucks cold air into the room.

my $.02


----------



## wilbilt (Dec 8, 2008)

peirhead said:
			
		

> ...has anybody ever heard of a pellet stove using outside air for the convection blower?



Yes.
See my crude diagram above.

The pedestal is open at the rear, which is where the air is drawn in. There are holes along the sides at the rear to attach a plate to enclose the back of the pedestal, and a 2" knockout in the base of the stove for an outside air connection from under the floor. I assume the block-off plate would also have a knockout for a through-the-wall outside air connection.

Either way, the fan supplies the air for both combustion and convection with no way to separate the two.


----------



## Scoop (Dec 8, 2008)

wilbilt said:
			
		

> peirhead said:
> 
> 
> 
> ...



That doesn't sound right.  You shouldn't be using outside air to heat your house. Too inefficient. There must be a direct connect somewhere for outside combustion air. 

my $02


----------



## Lobstah (Dec 8, 2008)

sounds like they were trying to save $$$ by going with 1 fan.

Jim


----------



## wilbilt (Dec 8, 2008)

Scoop said:
			
		

> That doesn't sound right.  You shouldn't be using outside air to heat your house. Too inefficient. There must be a direct connect somewhere for outside combustion air.
> 
> my $02



I also think it would be inefficient, which is why I haven't connected it.

There is no direct connection to provide air to only the combustion fan, since the same fan supplies air for both.

The fan is an axial fan, similar to a computer fan, but is about 6" in diameter. It is bolted to the floor of the stove and pressurizes the entire inside of the "cube" that is the stove body under the hopper. At the front of the stove at the bottom, there are holes in a baffle that lead to the area under the burn pot for combustion air.

At the top of the stove the heat exchanger tubes are open to the interior and pass through the top of the firebox and then out to the room. There is no ducting inside the stove whatsoever. It is just a pressurized box. Some of the air supports combustion and goes out the exhaust, and the rest goes out through the heat exchanger into the room.

I am ready to try hooking up outside air, to see if it helps the draft effect (i.e., push heat toward the leaks instead of drawing in cold). If it adversely affects the heat output from the stove, I will remove it and continue running it the way it is now.


----------



## wilbilt (Dec 8, 2008)

Lobstah said:
			
		

> sounds like they were trying to save $$$ by going with 1 fan.
> 
> Jim



I don't know what they were thinking. It is an old stove, and almost certainly a 1980s design. The manufacturer has been out of business for over 10 years, so it is difficult to find any information.

Practically impossible, in fact. I have been trying to locate a manual or other info with zero success.


----------



## Scoop (Dec 8, 2008)

An outside air connection is mandatory for pellet stoves installed in a mobile home so I think I'd hook one up. Your not heating that large an area so heating cold air shnouldn't make that much difference.


----------



## cac4 (Dec 8, 2008)

Scoop said:
			
		

> cac4 said:
> 
> 
> 
> ...



well, there is no "room";  its just "the basement".  24'x36' rectangle.  
there are cold air return ducts throughout the house...but that wouldn't have any effect on combustion air.   Maybe I should have an OAK for the burner...or maybe its the fact that its vented with a power-vent, rather than natural draft.  either way, it consumes a lot of air, and it has to get it from somewhere.  

Interesting thing I noticed: with the pellet stove running, I get a big draft coming UP from the basement.  Don't quite understand why.  The stove having an OAK in place would rule out "combustion";  maybe its just the hot air rising?


----------



## Scoop (Dec 8, 2008)

In Canada you would instal a Venmar heat exchanger, which bring outside air in for combustion but mixes it with the inside air, so it doesn't cost you money to heat the outside air. U likely have something similar down there. These units usually arfe required by code in new home constructin in colder climates. Somehow you have to get more air into your basement so there isn't  negative presure caused by combustion, IMHO.

Stan


----------



## SmokeyTheBear (Dec 8, 2008)

cac4 said:
			
		

> Scoop said:
> 
> 
> 
> ...



A 250 CFM combustion fan can remove all of the air in your 24' x 36' house foot print every 55.296 minutes provided the house has 2 floor equivalents each with 8 foot ceilings.


----------



## MCPO (Dec 8, 2008)

SmokeyTheBear said:
			
		

> [quote author="
> 
> A 250 CFM combustion fan can remove all of the air in your 24' x 36' house foot print every 55.296 minutes provided the house has 2 floor equivalents each with 8 foot ceilings.



A 250 CFM combustion fan is 2.5 larger than my bathroom ceiling fan. Any pellet stove using one that large should be brought to the junk yard immediately.
 I assume we are talking about a furnace fan?


----------



## SmokeyTheBear (Dec 8, 2008)

Nope not the furnace a pellet stove, they all have combustion fans and they can and do suck really well.

A furnace also can do a number if it is not set up correctly.  With the furnace you are not apt to really notice it since the doors to the living space are normally closed and the furnace area draws air from other sources such as the great outdoors (even without an OAK).  If you do a bit of research you discover that combustion based central heating systems can waste a lot of energy if they aren't setup properly and I'm not talking burn efficiency.


----------



## cac4 (Dec 8, 2008)

ok....but my pellet stove is using outside combustion air.  so what is "sucking" the air up from my basement??


----------



## SmokeyTheBear (Dec 8, 2008)

cac4 said:
			
		

> ok....but my pellet stove is using outside combustion air.  so what is "sucking" the air up from my basement??



Where is your stove located and what other devices with fans if any are you running in the house, any fireplaces, etc ... .

That air may be being "sucked" up due to temperature differences or pressure differences.


----------



## cac4 (Dec 8, 2008)

stove is on the first floor.  house has 2 stories of living space, plus the full basement (unfinished; poured concrete foundation), and attic space above.  everything should be sealed up pretty well.  House was built in 1994, has 6" walls full of insulation, double pane windows, etc.  
no fans running.  Clothes dryer lives in the basement, anyway.  

I've gone around with a candle to observe air currents with the stove running.  You can see how the air circulates around the open first floor areas.  At the top of the stairs, on the second floor, you can see warm air flowing up at the top, and down at the bottom.  Same in the bedroom doors.  hold the candle up at the top of the doorways, and the flame leans into the room.  hold it near the floor, and it points out toward the stairs.


----------



## SmokeyTheBear (Dec 8, 2008)

Well let's see.

Do your bathroom fans have a damper on the outside vent that closes tight when the fan is off?  Same for your dryer.  The outside air blowing (wind) past any vent will cause a pressure difference.   

Improperly trapped plumbing could also allow outside air blowing past the stink pipe to remove air from rooms with the messed up plumbing.

Also remember cold air falls and will draw a flame as well.

The intake for convection blower on your stove is likely to be low to the floor and will also cause a pressure difference between one area of your house and another.

Does your house have a chimney?  If so are there any air leaks around anyplace along the walls surrounding the chimney?  You might also wish to check for an air path in the race the chimney is installed in.  Just stuffing fiberglass into the small voids around a chimney race won't seal the pathway.   The same types of things should be checked around all electrical outlets including those on inside walls, you'd be surprised what you might find.

The vent on your stove should be treated like the bathroom vents.


----------



## cac4 (Dec 8, 2008)

no bathroom vents.  I doubt anything is wrong with the plumbing;  its very straight-forward.   dryer vent  has a louvered plate outside, so its closed when the dryer isn't operating;  how "tight" it is?  well...I doubt its very tight.  furnace exhausts through a power vent.  

there is a chimney, of sorts...wooden chase for a "decorative" fireplace.  the type that doesn't throw heat.  its slated for removal.  Meanwhile, Its covered over with that 3M window film, to prevent drafts.  

the only thing really "blowing" is the pellet stove, itself.  

I expected cold air to drop down into the basement when I open the door;  but it seems to be rising up...hence, the puzzle.


----------



## SmokeyTheBear (Dec 9, 2008)

If it is occurring when you open the basement door it is following the pressure difference caused by the convection blower, keep that basement door closed and check for air leaks.

You only want to heat the living space envelope air.

No bathroom vents could be a possible mold issue eventually.  I also think that under current code they may be required.  Maybe a window would qualify but I haven't dug around in building code issues in some time.

How about a stove vent?  Those are frequently vented to the outside and need a damper on the end as well.


----------



## sydney1963 (Dec 9, 2008)

The temperature of the combustion air is not a significant factor.  If anything, the fire will burn hotter with colder air, because cold air has a higher concentration of O2. Period.


----------



## wilbilt (Dec 9, 2008)

sydney1963 said:
			
		

> The temperature of the combustion air is not a significant factor.  If anything, the fire will burn hotter with colder air, because cold air has a higher concentration of O2. Period.



I'm taking your word for it. Hoping to get the OAK fabricated this weekend.


----------

