wood stove over drafting?

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vasten

Member
Hearth Supporter
Nov 11, 2007
205
Upstate NY
I just installed a regency FS1100 wood stove. I have it connected to a Class A chimney going straight up and out of the roof, "no Elbows". It terminates approx 4' over the roof penetration and the entire langth from stove to termination is approx 20'. The only damper is the stove air intake one, I do not have a pipe damper. Ofcourse with going straight up and out the pipe is within the building. I did by the stove used, and it is stamped 1997.

It has been installed for about 1 week now. What I am noticing is when it is warm out 40-50 the stove works great, when it gets into the 20's the stove doesn't perform as well. The fires are harder to start, they tend to smolder more, and the stove doesn't stay as hot. I can hold my hand 2" from stove top and count to 10-15 before having to move my hand. One intersting thing was this morning when I change the damper setting not sure to where, but a few minutes later my son told me that stove popped and smoke came out of it. I am assuming that may have been the gases building up that ignited and made the pop sound he heard.

I had one heating guy tell me that with out a pipe damper that alot of heat is going out of the chimeny, and it got me thinking that maybe the stove is sending too much heat up and out and therefore cooling the firebox down below an acceptable temp. Never burned wood before so just a guess there.

I use pallet wood for kindling and sometimes have burned it exclusivly as it keeps the temp high in the stove and house. That seems to work, I put chord wood in and it dies right out. My chord wood came from standing or fallen dead wood on my property.

Also I am not able to damper the air intake down to its lowest setting as it will basically put the fire right out. I have to run th stove at full or 1/2 intake damper.
 
It sounds like the cord wood is not seasoned enough. If not, and you have been burning it regularly in combo with the pallet wood, this might be creating creosote.

Go out and take a closeup look at the cap on the flue. Is it screened? Is the screen starting to clog? If it is, time to have the chimney cleaned and to switch to drier wood.
 
K, I will check on the chimney once it cools enough, from the ground it looks good, I am not one to go up on the roof if I can avoid it.

Any thoughts on the pipe damper?
 
20' of pipe is generally the range where I start to hear of people saying they are getting an overdraft. But, overdraft symptoms usually include a fire that burns too hot with no ability to slow it down - even closing the air down doesn't slow the fire enough.

You symptoms sound somewhat different with smoldering fire, back-puffing, etc. What seems to be happening in your case is the flue gases cooling off too much while in the pipe. Once the gas cools, it doesn't rise anymore and can start to 'plug up' the pipe. When the outside temp is warmer, the flue gas stays warmer and you are operating in the 'green zone' When the outside air cools, it pulls too much heat out of the flue and you get to a 'red zone' where you aren't pulling enough draft to keep the stove hot and maintain the draft.

You may post some additional specs - diameter of the pipe, insulation or wall thickness of the pipe, if it changes for different sections, interior / exterior sections of pipe, etc. See what others chime in with, but I suspect you may have a fair amount of single wall pipe. if that is the case, the solution may be to apply a little bit of pipe insulation, or switch to an insulated pipe for more of the run. That will keep a little more heat in and give better draft.
 
Sounds like you are getting less draft when it is colder? How would a damper help? This is the opposite of logic. As other said, is your wood seasoned? How long has this "dead" wood been cut split and stacked? How long was it dead? Is it starting to rot at all?
 
vasten said:
K, I will check on the chimney once it cools enough, from the ground it looks good, I am not one to go up on the roof if I can avoid it.

Any thoughts on the pipe damper?

From the info given, a pipe damper is not required. It might probably make the situation worse. Get a big box of good dry cord wood and try that out. If it works fine, then the problem is with the cord wood. Be careful with the palette wood, it can combust very quickly. Using it to start a fire is ok, but it needs to be treated with respect.

Also, get a stove top thermometer. When burning, don't choke the fire down too quickly, especially the first fire. You want the stove to get hot first. The wood should be charred and stove top temperature about 500-600 degrees. Then try dampering it down half-way.

Dampering it down too soon and too far, may fill the firebox with smoke if it chokes the flames. When (and if) the fire ignites again, all that unburnt wood gas can combust rather violently. I think that is what your son saw. This is why it is so important that the stove installation is done by the book, especially the part where each pipe connection has 3 screws. You don't want things falling apart with a hot fire going.

Considering you are just learning to burn, try to stay close by the stove, especially when you change settings so that you can watch the results. It takes time to learn how to burn wood correctly. You'll get the hang of it overtime, but don't rush off and try to do something else at the beginning.
 
The damper part was to keep the temp up in the fire box, thereby increasing the temp of the exhaust. However it looks like it was wet wood. I took a handful of pallet wood and ran it through the splitter and broke it up into kindling size wood and started over again. Once it took off it smoked like heck and then puffed black smoke for awhile. then I split some fresh wood from neither one of my stacks. and filled the fire box with that. Now I can damper the stove down again and see both coals and secondary combution. I seem to be back in buisness. I have learned to bring my wood inside 24-48 hours to ensure it is dried out first. before putting it in the stove. I was taking if from the porch and putting it right in the stove.

Also If it was dead timber when I cut it a month to two ago shouldn't it be seasoned enough?

It is 6" flue since wall to the ceiling then double wall class A the rest of the way. All 6" straight on through.
 
Good, the stove setup is probably fine. You have wood with high moisture. It will burn poorly and create a lot of creosote quickly. Wet wood will not dry out in 48 hrs. It takes an extended period to dry. Temporarily storing it on a covered porch is fine as long as termites or ants is not a problem.

The best way to check your wood moisture is to pick up a moisture tester. Split open a piece and test the freshly split side with the meter.

Dead wood lying on the ground will not be dry. But the cord wood may be ok if it was dry, off the ground and dead for a couple years. What type of wood?
 
I can not say what type of wood it is, other that maple ash or oak. Most was standing dead, some was on the ground. When it drops off the splitter onto the concrete in general it sounds like a baseball bat and seems light for its size. I started cutting and splitting it in september. I have one stack on a pallet that has been stacked for probably two months now, where the sun and wind can get to it.

The flames have died down now, I opened the door and there is a coal bed about 1-2" thick and hot enough that it was uncomfortable to have my hand too close to it. When I moved them away from the intake channel, as it mentioned to in the manual.

I went outside and there is no smoke coming from chimney.
 
Some of your wood may be dry and some may not be. Even if it's been standing dead for a couple years it can hold alot of water. A few minutes after reloading open the door and see if your wood sizzels. If it does it's still wet. Maybe you can store some next to your stove to dry it out more or mix it with dry wood and burn a little hotter.
 
I am storing some of my wood inside now next to my stove, and a buddy of mine suggested resplitting it again before bringing it in. To ensure it is dried out. some of these pieces "POP" and launch forward off from the splitter. I am assuming that is because they are really dry and good hard wood. but then again first time with all of this so just guessing.

Would storing the wood covered up outside be better than inside? thinking that dry windy winter air would suck moisture out, then bring it inside to warm and dry before using.
 
I'd follow your buddy's idea, resplit some and bring it inside next to stove. As it gets colder the water inside the wood will freeze and won't evaporate as much.
 
Just want to say thanks for all of the great responses. I am anxious to see how the first winter works out with the new stove and a begining wood burner. I do know that I will be ordering precut logs as soon as I can for next year to ensure that they are as dry as can be for the season.

Wouldn;t you know with my luck, the fire wood suppliers are out already this year and the ones that have any left have already started jumping their prices. So far if went from 40-45 a face last year to 50 preseason to 75 now if they have any left. Next month only proves to be worse.

S oeven if I wanted to buy some and keep mine to season longer it doesn't look that advantages.
 
The best time to order wood is May/June. The prices will be better and you'll have a full summer to dry out the stack.
 
Vasten,

I had the same problem as you. I was new to burning wood and didn't know what the problem was. Then I got a stove top thermometer and all is well now. Like be green said. It is very important to get the temperature up to around 600 before damping down. Especially if the seasoning of the wood is in question. This includes when reloading. Let the new wood get nice and hot before damping down or kicking in the after burn.

James
 
Used stove from 1997? Enough has been said about dryness of wood and draft. Im' thinking when was the last time that stove was really cleaned out?

Fly ash has a way of blocking inlet air passages clogging secondary burn tubes in general the ## one reason used stoves performance degradation

Another factor what was the stove's condition what shape are the burn tubes the baffle insulation. 10 year old stove usually would be on its 3 set of gaskets.

I have a fair share of using used stoves and prep them prior to installation. What was your prep routine?
 
Good point about prep routine. Since I am new you can imagine what it was. When I bought the stove, the seller told me that brinks where replaced two seasons prior, he cleaned and resleaded it at the same time. With that being said we also have to keep in mind that he is selling something too, so take it on face value.

The only thing I did was to take a shop vac and suck out any ash that I could find in the fire box or between the baffle bricks and the chinmey pipe. then I took my hand and swept through the chimney opening and moved any remaining ash that I could feel around in there and got that cleaned out of there as well.

Visually the stove looks good, when it is running you don't smell smoke, the air tubes do show signs of wear, little rusty. I do see the secondary combustion occurring, that is what tipped me off to there being a problem the other day, is when I had the stove running for 2-3 hours and dampened it down the secondary didn't kick in.

My plan for now is to buy a stove top thermo, and a pipe thermo and see how they read. From those readings I will then know how much heat is going out of the house through the flue, opposed to out the top of the stove. As well as when to dampen it down.

The stove should be 500-600 and the flue about half of that. So 500 at the stove should be around 250 on the flue.
 
my cleaning routine is I remove all possible parts bricks included using a vac with a dry wall dust filter is a must to keeping a marriage relationship on an even keel

Really before every season I remove both stoves out side and blow them out with compressed air shop vac them and wire brush screwdriver putty knife and get as much ash out as possible I will also duct take a clear plastic tube to the shop vac to get in places the larger diameter hose can't. Blowing them out with the compressor creates a dust cloud that will expose every point of leakage and also expose gaskets not sealed properly. Not many are willing to go to this extent , but I must say my stoves preform predictably and consistent.

my suggestion is to do the best you can in getting out as much fly ash as possible It could just be it is blocking air passages and robbing you of performance
 
Wow, with a cleaning routine like that, it begs the question did you ever have a pellet stove. That is very similar to the routine that I had to go through on a monthly basis with my pellet stove. I found out a hammer and bottle brush proved to be worth their weight in gold. Who knew how much fly ash could be found by beating on the inside of your stove with a hammer, not to mention it has done wonders for my hearing.

Today it has been around 35-40 out side and I have been running the stove on kindling fires. I would heat up the stove with two to three good loads of kindling to get it up to temp, and create a good coal bed then let it idle, with the air intake closed until the fire went out then opened it up to about half. just repeating that all day has kept the houst at a comfortable 72-76.

Yet lastnight it got down into the 20's and I just let the stove burnout and used the furnance, it felt like the stove couldn't keep up. That could be operator error, or the stove is too small or got more of the wet wood. Alot of factors that time will tell.
 
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