Stove temperature worries me.....

[DamienBricka]

I have the small CFM-FW240007.
Every time a fill up the stove with 4 large logs, (I cannot put any more large logs in) after an hour the temperature shoots to around 950F after a half hour I got worried and cut off all the air supply to the stove. And I also close the damper that I have on the stove pipe. It took over an hour to control the fire. Should I be concern? Since I am a newbie I am not sure at this point if I can load the stove to full capacity. Need suggestion and advice to move forward. Thanks in advance.

 

[fossil]

It's not how much wood you put in, it's how you let it burn. Once the fire is established, it's time to start decreasing the air. Maybe in 2 or 3 increments over 15 minutes or so. If the fire is burning nicely, you should be able to shut the primary air completely and watch the secondaries. Don't wait until the temp is 950ºF before throttling down the primary air. Start at maybe 450ºF or so.

 

[rideau]

Can you give a bit more information about your burn technique? It sounds as if you are not shutting the air at all until you are an hour into the burn and hitting 950 degrees.

If that is so, then try cutting the air back much sooner. Not familiar with your stove, but if it is a non-cat, then I would certainly be starting to cut the air back no later than when the stove top hits 500 degrees.
You can cut it way back, gradually, just maintaining a good burn.

 

[DamienBricka]

So if I understand you correctly I am cutting the primary to late and I should do it earlier

 

[fossil]

So if I understand you correctly I am cut the primary to late i should do it earlier

That's what it sounds like to me.

 

[Beer Belly]

I had mine starting to get away this morning.....tossed in a few small Oak splits to get'er going....next thing I knew, I'm looking at 850* and climbing.....tried to throttle it back, but wasn't happening quick enough for me....slowly opened the door to let the heat out, and boy was it hot...but it did cool it down after a while

 

[DamienBricka]

I will be more careful then. Fossil my next question is what is the longest burn time I can get from the stove, from your experience?

 

[EatenByLimestone]

I cut it back as soon as the secondaries start rolling as that means the firebox is hot enough and the burn is clean. The rest of the stove will heat up soon enough.

 

[DamienBricka]

I guess I still have a lot to learn about burning wood.

 

[rideau]

We all have to learn. Yes, cut the air back sooner.

 

[DamienBricka]

I hope that by having these high temperatures I did not damage the stove

 

[fossil]

I don't think you hurt it any, just watch that temp from here on out and start throttling the air before the thing's a raging inferno and the temp is skyrocketing.

I don't really think I can give you any meaningful info on burn times, because I burn exclusively softwoods, while I'm sure you burn hardwoods. You can achieve longer burns than I...provided you manage the stove carefully. When the fire is burning much hotter than you want it to, you're burning up your wood faster than you need to.

 

[fossil]

Matt (EatenByLimestone, above) knows this stove as well as anyone I know of. Pay attention to what he has to say about the Century.

 

[DamienBricka]

Fossil said; "When the fire is burning much hotter than you want it to, you're burning up your wood faster than you need to"

I did not know that so I will be more careful at controlling the burn so I can burn less wood.

I just learned and awesome lesson: Hotter burn does not mean more efficient burn.

 

[DamienBricka]

Fossil said: Matt (EatenByLimestone, above) knows this stove as well as anyone I know of. Pay attention to what he has to say about the Century.

I already have learned a lot from him and thank you for referring me to him.

On an other note this little stove is heating a 1300 square feet house very well. With the temperatures we had the last few days ( 10F) it kept the temperature around 70F in the house. Only down fall is reloading in middle of the night.

 

[begreen]

Be sure to burn down the coal bed a bit before reloading, try 30 minutes with the air wide open. Then after reloading on hot coals watch the fire closely. If the wood is dry and quickly ignites you can close the air down after only 5-10 minutes. Close it down until the fire gets lazy, then wait 5 minutes, then close it down further until the flames get lazy again. Repeat until the air is all the way closed or the flames stay lazy. Sometimes depending on the wood and coal bed you can close the air all the way down after just 10 minutes. Let your eyes be your guide.

 

[DamienBricka]

Be sure to burn down the coal bed a bit before reloading, try 30 minutes with the air wide open. Then after reloading on hot coals watch the fire closely. If the wood is dry and quickly ignites you can close the air down after only 5-10 minutes. Close it down until the fire gets lazy, then wait 5 minutes, then close it down further until the flames get lazy again. Repeat until the air is all the way closed or the flames stay lazy. Sometimes depending on the wood and coal bed you can close the air all the way down after just 10 minutes. Let your eyes be your guide.

I just realize I am really paying attention to the fire. Sometimes I rush and close it to soon and other times I wait to long to close the primaries. I seem to start to understand why i am burning more wood then I should. Thanks begreen for the sound advice.

 

[Chuck the Canuck]

I had mine starting to get away this morning.....tossed in a few small Oak splits to get'er going....next thing I knew, I'm looking at 850* and climbing.....tried to throttle it back, but wasn't happening quick enough for me....slowly opened the door to let the heat out, and boy was it hot...but it did cool it down after a while

So Beer Belly, did you open the damper or just leave it completely shut before you opened the door slowly? I'm getting ready to practice my door opening so I'm ready in case the stove tries to take off and go nuclear on me....

 

[WiscWoody]

I had mine starting to get away this morning.....tossed in a few small Oak splits to get'er going....next thing I knew, I'm looking at 850* and climbing.....tried to throttle it back, but wasn't happening quick enough for me....slowly opened the door to let the heat out, and boy was it hot...but it did cool it down after a while

If I open the door on a hot fire it gets hotter yet. I have a lot of height of stove pipe and class A vent pipe, around 22 feet so it has a healthy draft when its hot. Damien- after a season or two of using your stove it'll be second nature to you as far as controlling the fire. It took me awhile to get it right too and I over fired the stove a few times the first winter I'll tell ya!

 

[Beer Belly]

I had the air totally cut off....just opened the door slowly, and it cooled down.....not sure if having the air supply cut off when opening the door was the right thing to do, might have had the sudden supply of air when opening the door cause a problem, and just got lucky that it didn't this time....but in my situation, it worked to cool things down. I did go to my manual to see what they consider an overfire temp, and it states if the stove glows red, you may have an overfire.....I thought it would give a spec, or something ?

 

[EatenByLimestone]

If the wood is dry and quickly ignites you can close the air down after only 5-10 minutes.

This is important to note as a good deal of the wood's energy is burned off as the wood is starting to catch. If the draft is still running wide open it goes up the flue. If it's closed down it gets completely burnt in the stove.

I just realize I am really paying attention to the fire. Sometimes I rush and close it to soon and other times I wait to long to close the primaries.

On keeping the primary open too long, don't sweat it. It happens.

Paying attention to the fire is more important than paying attention to the little temperature gauge. The look of the fire will tell you if you are burning too hot. The look of the fire will tell you if you are burning too cold for a clean burn.

Hotter burn does not mean more efficient burn.

Well, yes and no. A hotter burn does help your stove burn the load more completely, producing less particulates. The EPA would consider that an efficient burn. I don't think they are worried about burn times though. We're all looking for a compromise on clean burn and long burn time. Watch for smoke leaving the flue and the flames of the fire/secondaries. Try to find out how cool of a stove top you can have and still get an efficient burn.

 

[Christopix]

Great little thread!

 

[jatoxico]

I have the small CFM-FW240007.
Every time a fill up the stove with 4 large logs, (I cannot put any more large logs in) after an hour the temperature shoots to around 950F after a half hour I got worried and cut off all the air supply to the stove. And I also close the damper that I have on the stove pipe. It took over an hour to control the fire. Should I be concern? Since I am a newbie I am not sure at this point if I can load the stove to full capacity. Need suggestion and advice to move forward. Thanks in advance.

Damien, sounds like you're getting usable heat so progress being made. I didn't see that any one mentioned it but 950 F is too hot. At no point should any part of the stove glow including dull red that can only be seen in low light.

 

[tcassavaugh]

i have to agree with the rest of the knowledgeable folks that have already posted. i'd turn your air down sooner. also, i'd use your key damper to help control the burn too (jmho). i use the magnetic rutland thermometer i have on my pipe to help control my burns. once the temp gets up into the "best burn" area on the pipe, i close down the main air on the stove to about 25-50% and i turn my key damper to about 10 or 2 o'clock. normally, it will settle down and cruise at about 400 or so for quite awhile (pipe temp). not procedures for everyone, but it works for me.