How hot is a hot burn?

[PipNH]

I know you're supposed to do a hot burn in the morning to burn off any creosote that might have built up in the night, but how hot and for how long are we talking?

My stove top thermometer gives me an optimal burn zone of between 300 and 500 degrees. I know it might not be accurate because it's on the stove top and not on the pipe, but I have a double walled pipe and don't like the idea of drilling a hole in it (neither, by the way, did the guy who installed it.)

What stove top temps should I be aiming for in the morning?

 

[saydinli]

Its not uncommon to cruise at 600-700F stovetop but you really don't want to get much higher than that. Don't worry about drilling a hole in the pipe but if you don't want to, its perfectly fine to reference the stovetop temps.

 

[MDWOOD]

PipNH,

Is it really a stovetop thermo or is it just on the stovetop?

look on the thermo package, Does it say to put on stove pipe?

Optimal burn zone of between 300 and 500 degrees is temperature on the outside of single wall stove pipe.

My stovetop temp likes to be at 700

Its fine to use a stovepipe thermo on a stove top just disregard guidance and go by temperature

 

[Nick Mystic]

I'd like to see some actual data supporting the notion that burning your stove "hot" for a period of time burns off the creosote that might have built up over night. We all know that the most creosote build up occurs at the top of the stack and inside the rain cap. I seriously doubt you can burn a stove hot enough that you can get your exhaust gasses to stay hot enough to affect that creosote build up. In my experience it takes a direct flame to catch creosote on fire. We're basically talking about a chimney fire. Yes, a hot fire can affect (burn off) creosote that has built up around the stove collar and perhaps the lowest section of the flue, but I suspect normal burning practices will do the same thing. Why risk damaging your stove by over firing it when normal burning and sweeping will work just fine?

 

[kennyp2339]

I'd like to see some actual data supporting the notion that burning your stove "hot" for a period of time burns off the creosote that might have built up over night. We all know that the most creosote build up occurs at the top of the stack and inside the rain cap. I seriously doubt you can burn a stove hot enough that you can get your exhaust gasses to stay hot enough to affect that creosote build up. In my experience it takes a direct flame to catch creosote on fire. We're basically talking about a chimney fire. Yes, a hot fire can affect (burn off) creosote that has built up around the stove collar and perhaps the lowest section of the flue, but I suspect normal burning practices will do the same thing. Why risk damaging your stove by over firing it when normal burning and sweeping will work just fine?

I suspect that the tail starts off from the pre epa stove days when people would load there stoves up and bank it so low that the load smoldered through the night to get that all night burn. The idea was to heat out un-dried creosote coatings that might have occurred in the smoke pipe so it could drip back into the stove or evaporate out. Lets face it, in a chimney your going to get cooler towards the cap and even with the hottest of fires your not going to be able to get rid of any build up at the top of the chimney unless something lights in the lower portion. Of course with todays epa stoves with air adjustments that will not fully close and re-burn effects or cats, the whole idea of burning wide open for the chimney's sake is misleading at best, especially if you burn seasoned wood.

 

[PipNH]

Those are good points. Never considered them. Thanks guys

 

[Squisher]

It's meant to help to convert glaze or liquid creosote to a nicer form of creosote before it sets up hard. The morning after hot burn that is. It's not meant to literally burn it off.

 

[Squisher]

heres the link I was thinking of. And will answer the question better than I.

(broken link removed to http://www.chimneysweeponline.com/hoburnout.htm)

 

[Squisher]

To the OP. Your stovepipe thermometer does not indicate proper stovetop temperatures. As was mentioned you need to burn hotter on the stovetop than the stovepipe. If you hover around 300-400 you will not achieve robust secondary combustion.

 

[xman23]

I'm with Nick on this. The only hot burn I do is to burn off the blackened glass. My wife feeds the stove during the night, and from time to time she runs it a bit to cold. To clean of the glass I need a full firebox running around 500 degrees for about an hour. Right now shes running at 400 on the stove top.

As to monitoring the chimney temp, you don't need to. The stove top is fine. When you get he hang of it just look at the fire. To tell how your burning, after a few months, brush down the chimney and see what comes out.

 

[Squisher]

500 cleans your glass? Mine cleans up at 700-800 stovetop. I believe robust secondary combustion occurs around 500 stovetop for most steel baffle stoves without a fancy top/jacket.

It is much safer/better to burn a little to hot than a little to cool.

Did you read the link? It's not burning it off. It's converting it to a less nasty form of creosote before it sets up hard.

 

[Squisher]

It's not a matter of needing to monitor both but you should monitor both. If you were only going to monitor one I always recommend stovepipe, as that's what's actually going into the chimney.

Yes you can get the gist of were your fire is at by looking at it. Atleast some people can, but many can't even when they think they can. Heh I clean chimneys so I see it all the time. Customer, 'yes I burn really hot'. Me, 'do you use a thermometer?'. Customer, 'no I can just tell'. I always at this point envision a caveman beating his chest and pointing and hooting fire! Fire!

I would pose the question why wouldn't you get a much more accurate idea by using a thermometer? It's the cheapest part of this whole woodburning thing and one of the most important. The actual temperature.

 

[Squisher]

I will point out too if you are glazing up your chimney and clean bottom up and never go up top to inspect. You may not know that there's glaze by what comes down the pipe. Because it's not coming off without a battle much more rigorous than a quick whipping with a sooteater or scuffing with a brush.

Not directed at anyone in particular. Just emphasizing the importance of inspecting the topside and monitoring temperatures accurately.

 

[blacktail]

I don't run an extra hot fire for the sake of cleaning. On a full load, the top of my insert usually runs in the neighborhood of 600°. Anything between 500 and 650 is normal depending on how it's loaded and running.

 

[blacktail]

I do a mid season cleaning of my liner around the first of the year. One night last December I loaded my insert up before bed, had the air all the way open to get it going, then woke up on the couch 4 hours later. That whole load went up at full throttle. When I cleaned the liner, the stuff that came out looked just like always. Same quantity and consistency.

 

[Squisher]

The idea of burning hot the morning after is for when you damp down for a long overnight burn. If you just burn hot all the time it certainly isn't nescessary. And you should never overfire a stove for the sake of 'burning off the glaze'. I burn hot all day and usually try to settle my overnight load in quite hot too, but sometimes I'll get some glaze on the cap and last bit of chimney, never anything bad though as I burn hot the majority of the time.

If your wood is cured and you burn in the desired temp range you should never have to do anything 'extra' besides monitor your chimney and learn the cleaning frequency that works for your system and usage.

But it's not a wives tale to burn hot to clean up the chimney. It helps, and it's not lighting anything off. It's converting glaze and liquid creosote to a less offensive form before it hardens. That's it.

 

[Squisher]

If you are regularly burning hot you are constantly converting any liquid creosote to a more powdery form. So there is no need to do the hot morning after burn. You are doing it all the time.

If you damp down for extended overnight burns, it's a good idea to heat things up again in the morning. I think most here are already doing this just by running in the proper ranges to support robust secondary combustion.

The link. Explains it all

(broken link removed to http://www.chimneysweeponline.com/hoburnout.htm)

 

[Sodbuster]

500 cleans your glass? Mine cleans up at 700-800 stovetop. I believe robust secondary combustion occurs around 500 stovetop for most steel baffle stoves without a fancy top/jacket.

It is much safer/better to burn a little to hot than a little to cool.

Did you read the link? It's not burning it off. It's converting it to a less nasty form of creosote before it sets up hard.

Squisher, do you have a brand of stove top thermometers that you notice are more accurate that others? I've had some that are so far off from my IR that's its laughable. The last one just froze and didn't move. I like my IR, and can usually go by look and smell to know when the stove is hot. But for my wife and daughter a constant visual would be nice.

 

[Doc C]

I'd like to see some actual data supporting the notion that burning your stove "hot" for a period of time burns off the creosote that might have built up over night. We all know that the most creosote build up occurs at the top of the stack and inside the rain cap. I seriously doubt you can burn a stove hot enough that you can get your exhaust gasses to stay hot enough to affect that creosote build up. In my experience it takes a direct flame to catch creosote on fire. We're basically talking about a chimney fire. Yes, a hot fire can affect (burn off) creosote that has built up around the stove collar and perhaps the lowest section of the flue, but I suspect normal burning practices will do the same thing. Why risk damaging your stove by over firing it when normal burning and sweeping will work just fine?

I've always wondered about that.

 

[Easy Livin’ 3000]

Squisher, do you have a brand of stove top thermometers that you notice are more accurate that others? I've had some that are so far off from my IR that's its laughable. The last one just froze and didn't move. I like my IR, and can usually go by look and smell to know when the stove is hot. But for my wife and daughter a constant visual would be nice.

Wonder if that frozen thermometer could be lubed with some oil, WD40, graphite, etc.

I've trained the woman to use the IR. She seems to like the point and shoot and sometimes plays with the cat with the laser.

 

[xman23]

This morning i'm doing a hot burn. But it's 17 degrees outside and 60 in the house when I rolled out of bed. I was able to lite the splits on a small bed of coals. Now stove top is at 500 and I'm about to reload for the third time.

 

[Sodbuster]

Wonder if that frozen thermometer could be lubed with some oil, WD40, graphite, etc.

I've trained the woman to use the IR. She seems to like the point and shoot and sometimes plays with the cat with the laser.

No, something went wrong with the spring, and it wouldn't go back to zero. I tried a "manual" adjustment, and then it wouldn't go below 500, so it went in the trash.

We have two German Shepherds, a 3 year old and an 8 year old. The younger one loves the laser on the IR, and thinks it's a toy. The older (grumpy) one has taken it upon herself to assert her authority over all things fun and chase and growl at the younger when he goes for the laser. I literally have to sneak it out of it's hiding place.