Can Pellet stoves overdraft?

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Chrisnow86

Minister of Fire
hey everyone, i just bought a englander pellet stove the one rated for 2,200 sq ft. I like the stove it works well, but i noticed the glass does not stay clean, and also when the stove is running at a good clip with the feed rate on high the stove will vibrate and you can see the flame flicker and get smaller, im new to a pellet stove i had a Nashua woodstove before and burned about 9 cord a winter. now the way the stove is set up is like how the wood stove was, it goes from the 3" pipe to a 8" pipe then into the 11" x 11" flue. i opened the clean out door while the pellet stove was running and its was drafting quite a bit. i think its pulling to hard on the pellet stove and all my heat is going out the chimney. just need some input thanks!
 
A picture of your setup would help. What settings are your stove set to. Is the venting installed exactly as per the install manual? Pellet stoves are forced draft, meaning that the combustion blower generates and controls the draft over the firebox.
 
the manual says to go to at 6" max flu.. i figured this would be because the stove would not draft at all and i would have blow back. but the situation i have is quite the opposite affect, i dont have a picture of the the set up and im at work. the way its set up is simple i have a T to a 6" long pipe 90 degree elbow then into a 8" pipe that goes straight back to the flue. the flue height from the 8" pipe is about 22 ft tall
 
So you went into an 11"X11" flue even though the manual says 6" max!!! The chimney doesn't create the draft for the stove, the combustion blower does. One problem I see with your installation is that all that flue gas is gonna cool off in the chimney and condense. This equals creasote, and potential damage to the chimney, and possible smoke spillage into the home when the weather gets really cold. Pellet stove exhaust is much cooler than the exhaust from a wood stove, that's why they need smaller flues to prevent condensation from forming Usually you run pellet vent pipe all the way up, or line your chimney with a smaller liner. Please reread your install manual and make sure you follow it exactly. Not picking on you, just want to make sure it's installed safely. Please post pics when you can so we can see what's up.
 
the problem is if i open the clean out door at the bottom of my flue i feel a hurricane of air drafting up threw the flue.. this tells me the flu is drafting really hard and the colder it gets at night the harder the draft in the chimney is pulling on the stove.. if the exhaust gasses were cooling and not getting up threw the chimney it would back draft out the clean out door not pull even harder.. there is non issues with gasses getting out the chimney, plus with that issue comes what the call a "lazy flame" when air is not getting out the stove witch im having the opposite affect.. the flame burns really fast.
 
Pellet stoves DON'T (or, shouldn't) draft in from the exhaust... they have an intake manifold hopefully drawing outside air and a fan-powered exhaust pushing out up the flu.

You should have a 3", max 4" liner for a longer run, all the way up for best results.
you have an improper installation. Expect weird results.
 
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Well I know many years ago when I owned an englander stove on high it rumbled like you have stated. This was a straight thru the wall vent. If the chimney is not drafting you will not get a lazy flame, the stove creates it's own draft via the combustion blower. Flue gases will just lazily exit the chimney cooling below the condensation temperature on the way out. After a while you will start to see liquid oozing out of your flue. Trust me I have seen it. No matter what you are gonna need to run the proper liner down that chimney. A 11"X11" 22 foot high flue is an awfully large flue for a pellet stove. the rumbling that you are experiencing is not from the chimney, englanders just seem to do that when burning all out. Pull the stove and bring it outside and attach a small section of vent, crank it up and you will see it doing the same thing. Again I'm not trying to be critical, but if your house burns down your homeowners insurance is gonna look at these things, anything not installed according to the installation manual or to code can give them cause to deny your claim, even if it wasn't the cause of the fire. Insurance companies will try to find anyway not to pay.
 
A 22' run and the piping inside the house would make a lot more sense if you went all 4". I assume that 22' run right now is masonry lined, clay tile etc. You need to drop a pipe down there if the install instruction state so. It says max 6" right ? Why do you think 8" and 11" should work satisfactorily? The instruction are written for a reason.
 
the house is being torn down next summer so if i can get one winter with out spending a ton of money is what im looking for.. the house im building in place of it will have a 4 in flue installed so the stove will be hooked up better.. so for just one winter if i have to go up and clean the flue a couple times that wont bother me, i just wasn't sure if i was loosing heat out the chimney
 
Chris, First off, welcome to the forum! You do understand how pellet stoves work, yes?
 
yes you have a convection blower the blows the exhaust gasses out the stove and yes i know they dont need to draft.. and yes i know going in a large flu will let the gasses cool and condense and create creosote.. i knew that all along.. i was planning on keeping a eye on my chimney to make sure not build up would happen.. just never thought that it would seem to run the opposite.. i had a felling i might have a problem but i never thought it would be the opposite to what im seeing happen...
 
the house is being torn down next summer so if i can get one winter with out spending a ton of money is what im looking for.. the house im building in place of it will have a 4 in flue installed so the stove will be hooked up better.. so for just one winter if i have to go up and clean the flue a couple times that wont bother me, i just wasn't sure if i was loosing heat out the chimney
Its more than just cleaning the chimney now and then. You are creating a fire hazard for yourself and who ever lives with you. Expanding gasses cool and the result is creosote. Creosote is highly flamable and the cause for super hot chimney fires. You are expanding gasses beyond the limits of the stoves specified install diameter before they ever get to the chimney even. Another poster said it right. This is an improper install. Play it safe not sorry. You get that stove cranking on some cold Jan. Day and everything goes woof on you, its too late then.
 
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The rumbling problem is not from the chimney, it's inherent in englands stove design. When burning on high they tend to rumble and appear to "overdraft". It's just the way they are. That being said I understand you not wanting to spend the money right now to do it right. If it were me I would unhook it and run your central heat until your new house is built. Bad things can happen when heating appliances are improperly installed, ie chimney fires, CO poisoning, smoke spillage etc. Pellet stoves have the ability to produce a lot of carbon monoxide, far more than an oil burner. Some recent testing of wood pellet combustion in consumer stoves showed CO levels of 100-500 PPM, whereas a properly tuned oil burner emits less than 50PPM. As I and others have said, your stove is improperly installed and an accident waiting to happen. You are gambling with your life and your families life, no amount of money saved is worth taking the chance. If I thought my pellet stove installation presented a risk, it would be out of the house in a heartbeat.
 
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Good points everyone. The thing is the stove may burn ok for a while and then we get complacent. I lived through a chimney fire with a wood stove one time, improper install. Imagine that !! But it was a scarey incident, especially when the mortar started popping on the exterior of the chimney outside and you could see the flames through holes in the mortar. What saved the house was two courses of brick to the wall. Clay tiles can crumble from that much heat .
 
when it comes to chimney maintenance Ive never lacked on that i have had a chimney fire before and it took 4 fire extinguishers to put it out.. luckily no damage to my flue. but that was burning a lot of wood with a old Nashua (steal box with a pipe). my chimney is 4 layers of brick think and built very rugged with my wood stove i would clean the flue 3 or 4 times a year.. ive had pellet dealers tell me my flu would be fine (that was a enviro dealer) i will price out a liner tho
 
when it comes to chimney maintenance Ive never lacked on that i have had a chimney fire before and it took 4 fire extinguishers to put it out.. luckily no damage to my flue. but that was burning a lot of wood with a old Nashua (steal box with a pipe). my chimney is 4 layers of brick think and built very rugged with my wood stove i would clean the flue 3 or 4 times a year.. ive had pellet dealers tell me my flu would be fine (that was a enviro dealer) i will price out a liner tho
Look in your install instructions for your layout and follow that.
 
the house is being torn down next summer so if i can get one winter with out spending a ton of money is what im looking for.. the house im building in place of it will have a 4 in flue installed so the stove will be hooked up better.. so for just one winter if i have to go up and clean the flue a couple times that wont bother me, i just wasn't sure if i was loosing heat out the chimney

I am trying to do a pellet install on the cheap, temporarily putting it on an existing hearth with a large masonry chimney but it is lined with 6" liner, the max my manual specifies. I didnt want to cut holes through the wall, I may be selling the house soon or the pellet burner may go in to the basement, not sure. But attempting to make it the primary heater for this winter (not done with the install though).

However I wish I was more in your situation. If you are tearing your house down then no worries about putting a hole in the wall right? As long as its installed on exterior wall you can get the whole thing as a kit for like $200. That's pretty cheap chimney install. It cost me about $180 just in the pieces I needed to hook mine up to the thimble that was already above it on the hearth!

As far as your original issue, if you look around I've seen it often mentioned the Englanders often soot up the glass. I don't think they have a good airwash design, or no air wash on the glass? Not sure, I'll find out soon mine is built by Englands Stove Works too.

I'll go out on a limb not being part of the safety police here, but if the pellet stove is working fine and your only concern is dirty glass and flickering flame... and you were burning 9 cord per year with an old stove on the huge flu I assume you already well aware of the maintenance in cleaning the chimney. If you can't install at least a $200 proper venting then just monitor it closely.
 
Each stove is different. Harman has an install listed where you run either 3" or 4" pipe into a clay liner part way for instance. I believe that is through a fireplace as I recall. They show it that way or with a liner. But I'm pretty sure England doesn't show that. I could be wrong.
 
i agree, if the house is coming down, just take a 4" hole saw and go straight out the back
 
my house is cathedral and all open with lots of glass.. what stinks is i already thought about putting the stove in another location but there are no good places to put it so the heat will get to the rest of the house.. im stuck with using the chimney. if i gotta run a s.s. liner up the flue oh well
 
my house is cathedral and all open with lots of glass.. what stinks is i already thought about putting the stove in another location but there are no good places to put it so the heat will get to the rest of the house.. im stuck with using the chimney. if i gotta run a s.s. liner up the flue oh well
Just read your instructions, there has to be a diagram similar to your situation in there.
 
yes you have a convection blower the blows the exhaust gasses out the stove...
Not correct. The COMBUSTION blower pulls combustion air thru the stove and out the exhaust. The CONVECTION blower pushes interior air thru the heat exchanger and out the front of the stove into the room.
 
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