Chimney Fire and Eating Crow

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Feb 13, 2020
13
Idaho
Been burning wood for main source of heat for four winters. Just finished building a two story house. The chimney is roughly 28-30’ tall, straight all the way no bends. The HVAC guys used 6” from the ceiling box through attic out the roof. We then finished everything inside in 6” as well. Tonight puts us roughly 3 cords in this winter. Went to put on the logs after work, open the bottom of the stove (like im not supposed to) got the coals and logs hot enough to go and shut the bottom. Literally no different than any other night. Few minutes later start smelling burnt paint. Not real alarming since the stove is still new BUT i knew something was off because the stove was only a couple hundred degrees. Looked about halfway up the pipe in the room and saw the paint burning/smoking off on one section. I immediately shut the stove all the way down and took all the logs off. Within a few minutes the smoking stopped. Pulled the pipe apart where it was smoking and sure enough a good amount of flaky type creosote throughout the pipe up and down. Really flaky. Is 6” too small for such a tall chimney? Every morning and every night we try to get the stove to about 500-600 for about 30 mins to an hour or so before we damper it down any. Even when the stove is that hot, the single wall pipe just before entering the ceiling box is only maybe 165-180 at the hottest. Sorry for the long rant. Im super embarrassed and also a little gun shy. I take pride in burning wood. My father inlaw told me I should consider using bigger pipe but the HVAC guys had already started and I didn’t want to make them change anything.
 
Been burning wood for main source of heat for four winters. Just finished building a two story house. The chimney is roughly 28-30’ tall, straight all the way no bends. The HVAC guys used 6” from the ceiling box through attic out the roof. We then finished everything inside in 6” as well. Tonight puts us roughly 3 cords in this winter. Went to put on the logs after work, open the bottom of the stove (like im not supposed to) got the coals and logs hot enough to go and shut the bottom. Literally no different than any other night. Few minutes later start smelling burnt paint. Not real alarming since the stove is still new BUT i knew something was off because the stove was only a couple hundred degrees. Looked about halfway up the pipe in the room and saw the paint burning/smoking off on one section. I immediately shut the stove all the way down and took all the logs off. Within a few minutes the smoking stopped. Pulled the pipe apart where it was smoking and sure enough a good amount of flaky type creosote throughout the pipe up and down. Really flaky. Is 6” too small for such a tall chimney? Every morning and every night we try to get the stove to about 500-600 for about 30 mins to an hour or so before we damper it down any. Even when the stove is that hot, the single wall pipe just before entering the ceiling box is only maybe 165-180 at the hottest. Sorry for the long rant. Im super embarrassed and also a little gun shy. I take pride in burning wood. My father inlaw told me I should consider using bigger pipe but the HVAC guys had already started and I didn’t want to make them change anything.
If the surface of the single wall pipe is that low it is way way to cool. And you need to get the stove up to temp every time put in a new load of wood.
 
What stove is this for? What moisture content is your wood at?
 
Moisture content unknown. Wood is covered for typically a year or more then gets put into rotation. I primarily used single wall hoping that will help with heating but now knowing the pipe doesn’t really put much heat off should I switch it out to double wall to keep the heat more insulated in the pipe?
 
Moisture content unknown. Wood is covered for typically a year or more then gets put into rotation. I primarily used single wall hoping that will help with heating but now knowing the pipe doesn’t really put much heat off should I switch it out to double wall to keep the heat more insulated in the pipe?
Get a moisture meter. How tall is the connector pipe? And if you continue to use the ash pan to start the fire your stove won't last long at all.
 
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6" is what the F600 is specified for. You don't need a larger diameter pipe. If the stovepipe connecting to the support box is more than 8' long, it should be double-wall stovepipe.

The wood may not be fully seasoned, depending on the species. If it is oak, it will need at least 2 years to season.
 
How long is the inside portion of the chimney? ceiling support box in the attic makes me think that its a vaulted ceiling so im guessing here but you have a 15-20ft run of black pipe then ceiling support box and another 6-10ft of class a?
If that's the case and the black pipe in single wall the run is to long and that interior pipe should be changed out to double wall black to keep flue gases warmer, if the cost out weighs the benefit then send the chimney brush up the chimney once a month while burning.
 
yes you all are correct. Interior run is roughly 15’ of single wall stove pipe. Then in the attic through through the roof is at least another 12’ of class A. Would switching to 8” double wall pipe from the stove top to ceiling support box help anything? I almost think keeping it 6” but switching to double wall will help keep it the hottest. Price isnt the biggest factor. I just want to go to bed knowing Im not burning our home down. We burn pine 95% of the time. Thank you all for the help.
 
yes you all are correct. Interior run is roughly 15’ of single wall stove pipe. Then in the attic through through the roof is at least another 12’ of class A. Would switching to 8” double wall pipe from the stove top to ceiling support box help anything? I almost think keeping it 6” but switching to double wall will help keep it the hottest. Price isnt the biggest factor. I just want to go to bed knowing Im not burning our home down. We burn pine 95% of the time. Thank you all for the help.
Switching to 8" would make things worse. Switch to doublewall get a probe thermometer so you can monitor stack temps and get a moisture meter
 
Increasing the volume of the chimney will only slow things down when using a stove designed for a 6" outlet, a 8" pipe will only cool flue gases further and faster decreasing draft and increasing the chances of creosote formation / build up.
 
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6" pipe/chimney is exactly what you want/need. Just switch to double-wall from the stove to the ceiling...
 
You guys are awesome. Last couple of questions. 1.-how often should we be cleaning the chimney? Burning roughly 4-5 cords a winter. Once every spring WAS our standard. 2. Where on the stack would you recommend I put the probe? I have read 18” -24”’-36”. Thanks again everyone.
 
You guys are awesome. Last couple of questions. 1.-how often should we be cleaning the chimney? Burning roughly 4-5 cords a winter. Once every spring WAS our standard. 2. Where on the stack would you recommend I put the probe? I have read 18” -24”’-36”. Thanks again everyone.

Once you are burning properly with the proper double wall pipe you should be able to clean once per year but until then, you can sweep as often as you like to monitor buildup. I burn douglas fir, over 4 cords per year and only clean once per year.

The directions for the probe meter will specify this distance. I believe it is 18". I recommend the condar brand and it has proper temperature ranges that you should adhere to to prevent this buildup. Burning properly isn't about a short time at 500-600 per day, it's about maintaining a clean burn the whole cycle.

Especially with pine, you want seasoned wood and you don't want to smolder it.
 
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The dogs dont know what to do. They lay down by the stove then look at me like “whats going on here?” Caught the wife rubbing her hands together as she approached the stove this morning then quickly turned around “oh yea..no fire”
My 20 year old (seriously) chihuahua will bark at me if the house is cooling down and the stove isn't going.
 
Double-wall stove pipe will keep the flue gases hotter which will help prevent them from cooling down so much. You may also note an improvement in draft. The F600 is a good heater. With dry wood it should willingly run at 650ºF stovetop. Order a probe thermometer when installing the new stovepipe. Place it at roughly eye-level, around 24" above the stove.

If the flue system has been completely swept clean you can still burn while waiting for the new double-wall stovepipe to arrive. Just sweep more frequently. Maybe once a month until you can start burning dry wood. If there is a screen on the chimney cap be sure that is cleaned too.
 
Just in case you didn't pick up on the sense of urgency from Begreen or any of the others, with respect to opening the ash clean out to get your fire going, you definitely should NOT be using this method to help your fire along. Doing so greatly increases your chances of inadvertantly over heating the inside of your stove, and warping things, such as the baffle, or tubes or rails, or whatever. The aggressive inferno that occurs using this method can also cause welds to pop, thus creating ideal conditions for a very leaky stove that is very difficult, if not impossible, to control. And finally, any damage caused by this method will very likely be ineligible for warranty repairs. Bottom line, don't do it. If you absolutely must have more air to get your wood to catch, that is probably because your wood is not fully, or properly seasoned. In that kind of situation you can start up the stove with your door cracked open a wee bit, maybe for 5 or 10 minutes. Other than that, you may want to look into using some nice dry bio-bricks or something similar. There is no shame in being caught short without enough dry wood to do you for the rest of the winter, but it would definitely be embarrassing to have to admit that you overheated, and broke, your lovely wood stove.

Good luck brother!
Keith
 
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Yes absolutely. The manual says the side door is ok on start up, but never the ash door. Knowing I need to burn the stove hotter and for longe- hotter I will make sure I use the right size pieces of wood for the size of the fire. Im never going to put my family in that scenario again. Im lucky I was near the stove when it happened. Thanks guys. Ive got 15’ of double wall coming, cleaning rods and poly type brushes, and a stove pipe temp probe all coming hopefully by the end of next week.
 
Yes absolutely. The manual says the side door is ok on start up, but never the ash door. Knowing I need to burn the stove hotter and for longe- hotter I will make sure I use the right size pieces of wood for the size of the fire. Im never going to put my family in that scenario again. Im lucky I was near the stove when it happened. Thanks guys. Ive got 15’ of double wall coming, cleaning rods and poly type brushes, and a stove pipe temp probe all coming hopefully by the end of next week.

Let us know how the stove behaves differently with the double wall. I have 10’ of single wall above my shop stove and then 9’ of class a . I run it so hot that creosote is not a problem butthe double wall should keep the flue warmer so draft is stronger so I could reduce the intake air while keeping the stove hot. This should increase efficiency since we’re not blowing the heat up the stack.

I guess I’m just curious if a lower air setting will do the same job.
Thanks.