Ok guys so i have a moe all nighter wood stove. Not sure which one but it fits 18inch logs. It heats very well so i would hate to get a newer stove it does not have any baffle in it or anything. So i have been burning it and getting alot of cresote build up especially the tar like cresote. It has a 8inch outlet and its a newer block 8inch chimney i have my door drafts turned out one full turn on both knobs and have my pipe damper closed to about half thats where i always set it. My stove top will get to be 600-700 degrees or even hotter but my external pipe temps will only get to about 200-250 is this normal or what should i do to get my flue warmer as im assuming thats why im getting cresote so bad!
help with cresote build up with a moe all nighter new to all this
- Thread starter 14willog
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Jan Pijpelink
Minister of Fire
How dry is your wood? How long has it been seasoned? Wet wood is in most cases the cause of creosote build up.
I just don’t understand how my stove can be so hot but my pipe temp be so low
Jan Pijpelink
Minister of Fire
I have a heat gun and i do about 15inches above my pipe damper and my damper is about 20inches from my stove. My temp right at my thimble usually runs about 209
Jan Pijpelink
Minister of Fire
Jan Pijpelink
Minister of Fire
I measure about 300 F and a bit above on my single wall. Have you measured your moisture content in a fresh split piece of wood that has been at room temp for 12 hours or so?
No i have not i am going to get a moisture meter this week. Could it be that i just need to update to a newer epa stove?
That is way to low to dump into a clay lined chimney. There is no way you will keep the flue gasses above 250 untill the top of the chimney
Jan Pijpelink
Minister of Fire
I think you need to get an insulated liner installed. Measure the MC of your wood. As a test you could get a few packs of enviro blocks at Tractor Supply, burn them and see what temps you get, for comparison. Upgrading from that stove to a more modern one is not a bad idea.
Open the flue pipe damper more. The chimney is not hot enough.
Is the stove pipe 6 inch where you are measuring temp?
200* f surface temp is about 400* internal gas temp. Depending on flue diameter and height, this can drop below the required temperature of 250* to the top. That is the condensating point where water vapor from combustion condenses, allowing smoke particles to stick. If it is a 6 inch outlet stove connected to an 8 inch chimney, the expansion from 6 to 8 (round) drops by about 1/2. 8 x 8 square is even larger. So 400 in 6 inch expanded to 8 is only about 200*, cooling far below the critical temp to the top.
If you can get a temp reading on flue wall about a foot from the top you will know what temp the actual flue is. Keep it above 250 when smoke is present, and it will stay clean.
The flue damper is a chimney control that slows velocity of rising gasses in chimney. Opening it increases draft allowing more oxygen into stove, so you will be controlling stove by closing intake air dampers more.
You can see how an insulated flue the same size as stove outlet stays hotter with less wasted heat to keep it hot. Then you can run the air closed even farther using less fuel.
Is the stove pipe 6 inch where you are measuring temp?
200* f surface temp is about 400* internal gas temp. Depending on flue diameter and height, this can drop below the required temperature of 250* to the top. That is the condensating point where water vapor from combustion condenses, allowing smoke particles to stick. If it is a 6 inch outlet stove connected to an 8 inch chimney, the expansion from 6 to 8 (round) drops by about 1/2. 8 x 8 square is even larger. So 400 in 6 inch expanded to 8 is only about 200*, cooling far below the critical temp to the top.
If you can get a temp reading on flue wall about a foot from the top you will know what temp the actual flue is. Keep it above 250 when smoke is present, and it will stay clean.
The flue damper is a chimney control that slows velocity of rising gasses in chimney. Opening it increases draft allowing more oxygen into stove, so you will be controlling stove by closing intake air dampers more.
You can see how an insulated flue the same size as stove outlet stays hotter with less wasted heat to keep it hot. Then you can run the air closed even farther using less fuel.
Its an 8 inch all the way from the stove to the top and do you suppose that being the stove does not have a baffle of any sort in it that i can run my pipe damper all the way? Im affraid with that that my flames will be sucked out into the chimney. Also if i do that is there a way to control the stove temp because i have tried running it further open and man does that stove get hot i opened it up one night and the stove was 750 degrees
View my reply to him and tell me your input on that. I appreciate everything i have had many sleepless nights trying to figure this out.
A hell of allot better than filling your chimney with goop. Is your chimney interior or exterior?
Pictures would give us an idea of what stove you're working with. And its connection.
Try it with flue damper open. Close intake dampers down to a crack if needed to slow the fire.
Many people rationalize closing the pipe damper "holds heat in the stove". It doesn't. If you take temp readings before and after damper, you will see the same temp. It slows velocity of rising gasses, reducing draft of an over drafting chimney. If your stove is a double door, capable of being burned in Fireplace Mode with a screen in place, the pipe damper becomes your only control. It is there to slowly close until smoke starts to roll in at top during open door burning with screen in place. Open slightly for the correct draft that allows smoke out, retaining some heat. A single door stove does not require a pipe damper for open door burning, so they only need one in the case of an over drafting chimney. Keep it open with doors closed. Check temp at top, and IF much higher than 250, close it slightly to prevent too much heat loss. You can't close it much. Just slightly.
I'm still not sure if you have a 6 or 8 inch stove. That makes a difference if it can handle a baffle or not.
The stove should also be sized to the chimney, so a 6 inch outlet increased to 8 is part of your problem not getting enough heat into the chimney. If you have a 6 inch stove, use 6 inch pipe, line the chimney with an insulated liner, and baffle the stove.
The baffle must allow no smaller than the square inch area of stove outlet, pipe and chimney above it. (area smoke travels)
A baffle inside is advisable WITH a chimney that stays hot inside. Too much baffle retains too much heat in the firebox, not heating the chimney enough. The main advantage of a baffle is keeping the heat in the firebox, raising firebox temperatures allowing more smoke particles to be burned off in the box. It also adds resistance to flow inside firebox, requiring the flue damper if used to be open more. It will make the front of the stove hotter than the rear. Less smoke is less chance of particles sticking to flue walls forming creosote.
Try it with flue damper open. Close intake dampers down to a crack if needed to slow the fire.
Many people rationalize closing the pipe damper "holds heat in the stove". It doesn't. If you take temp readings before and after damper, you will see the same temp. It slows velocity of rising gasses, reducing draft of an over drafting chimney. If your stove is a double door, capable of being burned in Fireplace Mode with a screen in place, the pipe damper becomes your only control. It is there to slowly close until smoke starts to roll in at top during open door burning with screen in place. Open slightly for the correct draft that allows smoke out, retaining some heat. A single door stove does not require a pipe damper for open door burning, so they only need one in the case of an over drafting chimney. Keep it open with doors closed. Check temp at top, and IF much higher than 250, close it slightly to prevent too much heat loss. You can't close it much. Just slightly.
I'm still not sure if you have a 6 or 8 inch stove. That makes a difference if it can handle a baffle or not.
The stove should also be sized to the chimney, so a 6 inch outlet increased to 8 is part of your problem not getting enough heat into the chimney. If you have a 6 inch stove, use 6 inch pipe, line the chimney with an insulated liner, and baffle the stove.
The baffle must allow no smaller than the square inch area of stove outlet, pipe and chimney above it. (area smoke travels)
A baffle inside is advisable WITH a chimney that stays hot inside. Too much baffle retains too much heat in the firebox, not heating the chimney enough. The main advantage of a baffle is keeping the heat in the firebox, raising firebox temperatures allowing more smoke particles to be burned off in the box. It also adds resistance to flow inside firebox, requiring the flue damper if used to be open more. It will make the front of the stove hotter than the rear. Less smoke is less chance of particles sticking to flue walls forming creosote.
Jan Pijpelink
Minister of Fire
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