Average running cat temp

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Diabel

Minister of Fire
Hearth Supporter
Jan 11, 2008
3,862
Ottawa, ON
Just would like to know, what cat temps do you see during the burn cycle?
Say:

1hr in
2hrs in
4hrs in
7hrs in

Would be interesting to see cat behaviour on different stoves!
 
If Blaze King put a probe in with numbers on it, you'd get a lot of responses. I'll say mid to high side of active for a really, really long time.

And if Woodstock put a probe in at all...
 
I forgot that it was mentioned about no #s on probes that came with
Bks .....
 
I have had a totally different experience with this stove this year now that I have dry wood to burn.
Last year I struggled to keep it at 1000 or better but this year is a different story.

These temps are on reloads with plenty of coals left.


1hr in 1000
2hrs in 1300 to 1800
4hrs in 1000 to 1400
7hrs in 600 to 1000

Those would be pretty good estimates but depending on the wood and load of course. I loaded a mixture of pine, gum and some oak today and it ran up to 1500 in no time and was there two hours later when I left. Just got back after 5 hours (7 hours into the burn ) and it is 800 and still going strong.

Curious to see the other replies because I've been wondering this myself.
 
For our Buck 91 we are looking at above temps but stretched out by a few more hours.
 
I monitored my Keystone temps for a couple hours one evening when I was bored. I usually see it hang up over 1000 for about 3 hours.

Stove setting 1.5 20 minutes engaged the cat at 450

25 min- pipe 300, stove 290, probe 875
30 300 350 1000
35 300 420 1100
40 290 460 1200
45 290 500 1250
50 290 520 1300
55 290 540 1320
60 290 550 1400
stove setting at #1
65 250 570 1400
70 250 570 1350
75 250 570 1300
stove set to .75
80 240 560 1300
85 240 550 1300
90 210 570 1350
95 210 600 1400
100 210 600 1400
105 210 600 1400
110 210 580 1300
115 200 560 1250
120 200 550 1220
6am after 9 hours 200 400
 
eujamfh said:
For our Buck 91 we are looking at above temps but stretched out by a few more hours.

Yea, if I really load it up, it'll still be running 500-600 at about 10 hours or so. From what I've read and understand, if it drops below 400 the cat ain't eating anyway.
 
Seems to depend on a lot of factors for me... size of the load, how tight the wood is packed, the weather outside (draft strength), where I set the air.

Fill it up with a big load of small pieces on a really cold day and its easy to make it spike over 1600 :(

Typically medium load of 3-4 splits will cruise anywhere from 1100 to 1500 depending on air setting.

When I pack it for the night it will start off a bit sluggish but usually settle in around 1150-1250 on minimum air.


In general when its active and there is more than just coals in the box I never see anything below 1100.
 
Just an update: Now 9+ hours into the burn and the cat is still reading 500 and stove is still putting out good usable heat. I'm constantly amazed at how much heat it can put out without any real 'fire'. Just smoldering hunks that are feeding smoke to the big cats in the top of the stove.
 
The cat temp on my BK insert reaches temps of 2,000 within 45 minutes with a fresh load and the fan on high...... I have to start turning down the temp stat to get control of the temps. I would say it runs for several hours around 1,500 then the temps start to fade out. I try to do relaods at the 800 degree temp and it seems to work well.
I was concerned about the high temps and have replaced the door gasket last season with little to no effect on temps. I think the temps are higher because its sitting in the fire place and captures the heat. I removed the soft block off plate and have evan tried it with the surround taken off with little to no effect on cat temps.
the bottom line is it is heat my house and works great.
 
Ill look crazy if i sit near the stove with a stop watch. But id like to know. Shame i dont have a probe, ill have to give the estimates.

I figure these temps are dependant on the fuel? For example the oak i have is lasting at least an hour maybe more than the black locust i have. But the BL seems to put out more heat...
These temps are with your best wood?
 
My wiffe runs the stove during the day and reloads with 2-3 medium splits every 3-4 hours and maintains about 1100 cruise temp. Before bed, I load it up and it will get to about 15-1700. I'll watch it until I know the temp is stable or starting to drop. 6-7 hours later when I get up usually have a temp of around 600, throw in a few logs and were off to the races again.
 
Thanks guys for the input, especially Todd for nice & detailed analysis...

Back in Nov I installed a cat probe that was surly defective (I could not get the temp past 600*). Recently I installed a replacement probe & now I get readings of max 1200* which from what I read above tells me that it is still low. I think that my wood is not yet ready (two yrs c/s/s out in the yard for 6 months then into the woodshed....no other choice). The wood is mainly ash, elm & silver maple that I am burning at the moment. Also, I can only close the air about 1/2 way...if I close it any more than that cat temp will drop fast to about 400* and I will get smoke out the pipe. At 1/2 way air open I still will get nice long burns...7-8 hrs of usable heat....

Conclusion....wood that is out in the yard for 6 months then straight in the shed will not be ready after 24 months!
 
Ive learned to watch it like a hawk anytime I see the temp go over 1600. From experience Ive found that 1650-1700 sets up the right conditions to trigger spontaneous secondary combustion before the cat, resulting in the upper fireback glowing cherry red. very bad. Also Condars manual says anything over 1700 will degrade the cat.
 
I could see if your wood was all Oak but 24 months in a shed should be plenty for Silver Maple, Ash and Elm. Maybe something else is going on? Are those two ash pan holes clear? You should be able to close her down more than 1/2, how soon til you engage?
 
Yeah, I thought the wood should be ok but ....
I engage at around 450 griddle and always the cat will climb fast to around
1200 then will slowly drop to 1000 then sit there for few hrs then will start to
drop, and that is air at half open
 
Diabel said:
Yeah, I thought the wood should be ok but ....
I engage at around 450 griddle and always the cat will climb fast to around
1200 then will slowly drop to 1000 then sit there for few hrs then will start to
drop, and that is air at half open

How long does it take you to get to 450 and what does your probe say?
 
Todd said:
Diabel said:
Yeah, I thought the wood should be ok but ....
I engage at around 450 griddle and always the cat will climb fast to around
1200 then will slowly drop to 1000 then sit there for few hrs then will start to
drop, and that is air at half open

How long does it take you to get to 450 and what does your probe say?

It does not take long, maybe 10-15min (firebox full of flames), the probe will be cold at such point maybe 200* (remember this is VC where the cat sits at the lower back of the stove)
At 450* I will engage the cat, air full open and only at this point the cat temp will climb fast to around 1200*
 
Maybe the cat is shot? How old is it?
 
Todd said:
Maybe the cat is shot? How old is it?

Brand new SS cat put in Oct 2011
 
Diabel said:
Thanks guys for the input, especially Todd for nice & detailed analysis...

Back in Nov I installed a cat probe that was surly defective (I could not get the temp past 600*). Recently I installed a replacement probe & now I get readings of max 1200* which from what I read above tells me that it is still low. I think that my wood is not yet ready (two yrs c/s/s out in the yard for 6 months then into the woodshed....no other choice). The wood is mainly ash, elm & silver maple that I am burning at the moment. Also, I can only close the air about 1/2 way...if I close it any more than that cat temp will drop fast to about 400* and I will get smoke out the pipe. At 1/2 way air open I still will get nice long burns...7-8 hrs of usable heat....

Conclusion....wood that is out in the yard for 6 months then straight in the shed will not be ready after 24 months!

Standard symptom of wet wood. Wood will dry a lot, stacked near the stove for a few days. Better than stove being schmutz-source.
 
hmm... 450 griddle is on the lower side to engage on a VC unless you are starting off a really good coal bed. I have that stainless cat also but still have better results when I let it get to 550-600 griddle temps before closing the damper.

Something is definitely odd in your setup. If I leave my air control at 1/2 for long the stove would go thermonuclear.. even my first year with marginal wood I couldn't run it that high once the load had charred well. Time for the usual troubleshooting checklist I think. Try one pack of kiln dried grocery store wood. If you still have problems then time to check the chimney for blockages, check the manual that you have the right chimney setup, check that all 4 air inlets (primary, cat, and the 2 air holes in the ash pan) are clear, pull the cat and brush it out, etc...
 
Hm...I always thought that once the cat lights off it will stay lit until there is no more smoke to burn.
Mine will die if I close the air all the way (as said before) most natural reason is bad wood. I resplit
one of silver maple splits and it reads 19% moisture.

Here some history on the stove:

I got the stove for free from this older lady who mostly used the stove with bypass open.
The refactory was in decent shape as was the ceramic cat. I did strip the inner shell of the stove so I could shine a light to see
any cracks. There was one major one in the lower left corner behind the refactory.
I fixed it with cement put it back together etc. one of the upper firebacks bolts would not go in but other five were nice and tight. I put some cement
Around where the bolt should be....
Gaskets were nice and tight as per $ bill test. The stove burns very well I think (better than my old/new encore nc!!)
I did notice that without any ash in the firebox I will have some flame even with air fully closed. I decided to plug one of the dime size holes
near the ashpan, that helped a lot, now if I close air fully the flames will disappear. I still get nice overnight burns with lots of coals after 9-10 hrs but I feel
that I can get more heat out of this stove if I can bring the cat temps up...
 
Maybe you need to unplug that other hole and see what happens?
 
Yeah, thought about it. Simple to do with next ash removal.

Would it be possible that the stove is getting too much air and cooling the cat too much?
 
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