Smoke puffing out door into house

[Atward]

Hello,
This is my first post. I am new to using wood to heat my house and have found this site to be valuable. I bought an Appalachian 4 n 1 insert, and it is my primary heat source for a 1950's brick ranch. Today I got a phone call from my wife informing me that smoke was puffing out the door of the stove and the house was filled with smoke. I have seen small amounts of smoke puff out the vents, but never the sides and top of the door. I called the dealer when I first noticed the small puffs, and was told it was a small backdraft that probably happened bcs. of wind. I have a insulated stainless liner running up the chimney, cap at the top, and had the chimney cleaned and inspected before installation (which I did myself). I have not trimmed out the stove yet, so I have access to the increaser/ reducer and when I hold a lighter up to where it sets into the stove top the flame goes into the stove / pipe connection (air is entering the pipe there). Is this a negative pressure problem, stove problem, installation problem?

 

[Jerry_NJ]

Sounds like a negative pressure problem.

What else is running? How about a cloths dryer, over over-the-stove vent, bathroom vent... anything that pushes air outside. Is you central heat running, it could also be drawing too much air form the room with the insert.

How tall is your chimney? What's the outside/inside temperature. Do you (your wife) open the primary air supply all the way a couple of minutes before opening the door..or are you saying you're getting smoke into the room with the door closed?

 

[LLigetfa]

Sounds like a negative pressure problem.

Concur that is the likely culprit but here are a few other considerations.

If you don't have enough air to feed the fire you won't have a strong enough draft. Also, without sufficient air, the burn flip flops between smoke and flame whereby the smoke builds up and then ignites in flame resulting in a sudden expansion that the inadequate draft cannot remove. If you are burning wet wood, it will only exacerbate it. If you have a spark arrestor cap, you might be clogging it up, further reducing draft.

 

[Highbeam]

LL probably guessed it right. Check your chimney cap. The screen can easily plug up in only a few months of burning and since this problem is new I would say the odds are good. Plugged up screens will damage draft to the point of smoke from the door.

 

[Jerry_NJ]

For those of us with high chimney and steep roof, is it possible to examine, at least for major problems, the chimney cap with 10X Binoculars?

My new cap has about 1/4-1/3 cord of seasoned (mostly) hardwood (mostly) burned through it. Most of the times when I check the is almost no visible smoke, clean burning (smoke at start up, of course). I'd guess it is clear (enough), and my draft is good, very little smoke back out the door, a little only when I'm starting up and I don't leave the door open a crack long enough. Here I"m saying sometimes I close the door on start up and see through the glass a lot of smoke inside the firebox, and if I open the door I know I'll get a puff of smoke, but I do it sometimes anyway to get the flames back.

 

[Techstuf]

I concur with LL as well. I run alot of chimney with a big stove. I had intermittent problems synonymous with that which LL described. I bought an Auto draft regulator of the kind seen here:

And have not had a problem since. Been using one four seasons now and love it.


Once you set the disk weight mounted to the inside of the pipe valve, for the proper balance, you're good to go.



TS

 

[Highbeam]

Hi tech, that looks like a barometric damper. The sole purpose is to reduce draft. The poster already has too little draft which is exhibited by smoke pouring out of the stove instead of getting sucked up the chimney. Your device would only make it worse. Also, it is the least desirable form of damper since it introduces room temperature air to cool the flue (make creosote) and it also will get sucked wide open to supply a chimney fire with loads of combustion air.

 

[North of 60]

Absolutely, Highbeam.

 

[Techstuf]

@Highbeam

I can see the merits of your assertions. I could see how, if used improperly, this device, like many others, could increase risk. If mounted as originally intended, it does not introduce room temperature air but, more accurately, dry, stove top vicinity temperature air into the flue, which is not necessarily a terrible thing, depending on one's particular setup. Any creosote I've had to date was dry, flaky powder. Like I said, I've been using mine for 4 seasons now and it has performed as advertised, for my setup. It is my belief that wood stove setups of all variety and configuration should not be used at all unless their owners are prepared to judiciously monitor their use.

I can't speak for the experiences of others.

TS

 

[North of 60]

Can you not fathom what this does to your flue temps? If you are not burning near perfect seasoned wood, what creosote this could create. Then again with a chimney fire. A draft regulator again is what is used to slow down or decrease your draft. Clean burning fuels that have controlled content. re; coal, NG,LP ,Oil ect.... I could see it initiat a draft due to the warm air in the house, but with the stove operating the heat should be there to create this. Looks like the stove is starving for air VIA house negative or a restriction in the flue @ cap ect.

 

[Techstuf]

Well, as I am a second generation Arborist, I concede that I have been spoiled rotten regarding wood choice. My stove simply does not have the draft intake size to properly draft nearly 40 feet of chimney without opening the ash cleanout door a crack and really upping flue temps and burning past peak efficiency. I was getting monster back puffing until I installed mine. It's obvious that my setup is certainly not the aggregate optimum for the vast majority of wood stove users and in retrospect, should not have evangelized their use in the arguably cavalier manner as I have previously done.


As some of you can surely tell, I've not been the shiniest example of a "safety firster"....


Ignorance does breed entitlement.


One lives and learns.



TS

 

[JerseyWreckDiver]

Hi tech, that looks like a barometric damper. The sole purpose is to reduce draft. The poster already has too little draft which is exhibited by smoke pouring out of the stove instead of getting sucked up the chimney. Your device would only make it worse. Also, it is the least desirable form of damper since it introduces room temperature air to cool the flue (make creosote) and it also will get sucked wide open to supply a chimney fire with loads of combustion air.

Not exactly. It is a barometric damper. But it's purpose is to insure the draft alway remains even by allowing sufficient air intake from the lower end. There is a weight on them so they can be balanced for correct draw. Should you choke down your combustion air it normally chokes down your draft also as that is the only place it can come from. With a BD in place if the combustion air is choked down the damper will respond to the negative pressure at the top end and open a little and let air into the exhaust stream to keep the draft even, constant and flowing. Also if there is a gust of wind across the top of your pipe it won't draw air through the combustion chamber and increase the burn rate but rather pull the damper open and allow the burn to stay even.

"Also, it is the least desirable form of damper since it introduces room temperature air to cool the flue (make creosote)"
Balanced properly it would only make up for the air not coming in through the combustion intake. I don't think it would be enough air to create a substantial cooling effect. Certainly not sufficient to counter the effect of keeping the draft flow moving fast enough to allow exhaust to exit before it can cool and they are normally at the low point of the pipe, just over the stove, hardly room temperature. I would say stagnant, slow moving exhaust would cause more creosote.

"and it also will get sucked wide open to supply a chimney fire with loads of combustion air."
Interesting thought, probably quite valid. Keep your pipes clean, no worries.

 

[LLigetfa]

"and it also will get sucked wide open to supply a chimney fire with loads of combustion air."
Interesting thought, probably quite valid...

I can attest to that happening. Thirtysome years ago, I had a woodstove connected to the same chimney as an oil space heater and the oil stove had one of those barometric dampers. Now and then the damper would start swinging wildly and the oil stove would surge and puff like a dragon. You'd have to stop the damper swinging with your hand. Anyway, I digress...

I had a chimney fire higher up in the Tee and that damper swung wide open and sucked air in like a vacuum cleaner. I got up on the roof and poured water down the chimney.

 

[JerseyWreckDiver]

"and it also will get sucked wide open to supply a chimney fire with loads of combustion air."
Interesting thought, probably quite valid...

I can attest to that happening. Thirtysome years ago, I had a woodstove connected to the same chimney as an oil space heater and the oil stove had one of those barometric dampers. Now and then the damper would start swinging wildly and the oil stove would surge and puff like a dragon. You'd have to stop the damper swinging with your hand. Anyway, I digress...

I had a chimney fire higher up in the Tee and that damper swung wide open and sucked air in like a vacuum cleaner. I got up on the roof and poured water down the chimney.

Not sure about things above the Northern border but here in the states building & mechanical codes require a barometric damper on all oil burning appliances. I have one on my oil boiler. I've installed boilers and designed a BD into each one, set in the correct place and balanced properly, they work as they should. Also here in the states, building, mechanical & fire codes forbid a solid fuel burning appliance to share a common chimney with oil burning equipment, have for many decades, for obvious reasons. The argument is certainly something to think about. I guess if I had to have a BD on my stove, I don't, I would keep some sort of lid near by so if I had a chimney fire I could cap the BD at the same time as I would close the stove doors and seal the combustion air inlet. Again, keep your chimney clean... the fire didn't happen because the damper was there, it happened cause you didn't clean your chimney at the needed interval.

The damper does not in any way slow down the exhaust flow, to the contrary it keeps it from being slowed down too much. You may be confusing the BD with a draft regulator, a disc that is installed inline in the flue pipe and can be closed to slow the flow of exhaust. These are typical for a setup where you don't have an airtight stove and no way to limit combustion air. It's basically regulating the burn from the other end, totally different animal.

 

[Highbeam]

Remember though, in every single case, the barometric damper will open and allow room air into the flue. This satisfies some of the draft and reduces the draft at the stove. In all cases, this device will slow down the sucking which will pull smoke through the stove collar instead of out through the opened door. The baro damper absolutely slows exhaust flow through the stove, but I agree, not through the chimney cap.

This device is certainly not the way to prevent smoke from spilling from the stove door. Remember the point of this thread and start another one about barometric dampers which do not solve the current problem of spillage.

Overdraft can be solved with the BD, not important to the thread.
Underdraft can not be solved by a BD, not good advice for the thread.

Geez TS, you use some fancy words.

 

[Techstuf]

Highbeam, you are correct regarding my post being inadvisable for the thread topic. I somehow missed the word "insert" by the author. I've yet to see an insert one could even mount such an autodraft regulator to in the first place!

Geez TS, you use some fancy words.

I suppose if by 'fancy'....you mean words like 'ignorance' and 'entitlement', then yes, I guess you have me spot on.




TS

 

[Atward]

Thanks for the replies. I am burning some wet wood right now trying to make it thru the holidays before I hopefully get some properly seasoned firewood. I also got up on the roof, unhooked the cap and knocked some creosete out. So, we'll see. Does air entering the increaser/ reducer sound like an issue?

 

[CountryGal]

Our stove was backpuffing recently and I had the guys out to clean the chimney and stove on December 10th. I knew I would have creosote because last year's wood wasn't well seasoned.

I bought wood in March this year and my wood guy had it about 6 months and I've had it 9 months and it sure burns better. Anyway, we had some smoke when I would add wood and I knew it was time to have it cleaned.

Two days ago it started in again. WTH?? Actually set off my smoke detector in the hallway twice and was puffing at the ceiling cap too, so I called and they sent someone out today.

Turns out the "ceramic blanket" was being sucked up into the stove pipe. The newer stoves have a metal removable plate that prevents it but mine didn't. He made me a new blanket and put one of the plates in and it's much better. Actually I had asked when they cleaned the stove last week why they didn't remove the firebricks and blanket to clean and he told me he could get it good with his shop vac with the stove pipe removed. Guess not!

No wonder we had horrible draft with that blanket being sucked up the stove pipe. Just wanted to add this info to anyone who might have the same situation.

 

[Highbeam]

Hi CG, not all new stoves have the fiber blanket. Some do and I intentionally avoided those stoves. Seems like a bad idea.

 

[kevandhel2]

Hi, we are new 4N1 owners also. After sweeping the pipe we started noticing a puffing out the door vents. We got the book out and searched this site but nothing worked. Last PM, we took off the plate that covers the combusters and noticed a small amount of buildup on the catalyst so..... we got the air compressor and shot LOW flow air through the front. DISCO, It worked! New lession from new owners. Check your Cat....Hope this helps.