How Hot is Too Hot? Jotul 450 Kennebec

[TomH]

I've seen a few threads on here discussing thermometer placement etc on a kennebec stove. I've place mine in the front top as others have done. However, the manufacturer doesn't provide any temperature feedback at all!

I know someone with a jotul f600, and his manual states to put the thermometer on one of the 4 corners up top, and specifies a max temp to see at that point (corresponds to standard flue thermemeter "burn" range iirc).

What I want to know is, how hot, and where? How hot should the inside get? How hot should the flue get? And how hot should a thermometer on the top front get? Has anyone figured this out to some satisfaction?

 

[soupy1957]

I had a thermometer placed on the lip that overhung the top of the unit. I found that that particular location was telling me one temp, while a thermometer placed on the top of the stove told me another.

Then a caring soul pointed out to me that the flue temp is one of the most valuable reads I should follow and so I drilled a hole and put a thermometer there (18 inches above the top of the stove, as recommended).

Knowing what the fire is doing inside the box (visual) is for me, the foremost evidence of where I'm "at" in terms of conditions, and then secondly my flue temp (or perhaps equally).

"Typically" in MY setup, I see around 650ºF in the box, when the fire is going well. ("going well" for ME means I've got a glowing bed of embers and the secondaries are obviously engaged, and I've got a few splits in there). also "typical" at this point in the burn, the flue temps are somewhere in the neighborhood of 550ºF.

The thermometers I have, are designed with colored temp ranges. Having said that, I just try and keep both out of the "red" range. If I see temps getting into the red, I close the stove damper a tad (one thing I've learned about the stove damper, by the way, is that very modest moves can make significant differences. I've learned to make smaller adjustments, and wait a few minutes to see what effect my adjustment has had on the fire).

Seeing how the fire reacts, ...........not walking away from it right after I've tweaked it, or added more wood........making sure things are leveling off the way I'd like............are all part of my normal approach to safe and efficient wood burning.

-Soupy1957

 

[Pagey]

TomH, it will vary by manufacturer. Generally speaking, you'll find that plate steel stoves have higher temps listed as "overfire". For example, my Lopi Endeavor manuals states that surface temps on the lower plate (it's a step-top model) over 800F are considering an "overfire". You'll also find that (again, generally speaking) soapstone and cast iron stoves have lower overfire temps listed. Someone please correct me if I am wrong, but doesn't Hearthstone prefer 600F as a max surface temp on the top stones and Woodstock 700F? Inside the firebox, temps of 1,100F are required for secondary combustion in a non-catalytic stove, so if you have secondary combustion taking place, you know you've reached at least that temp.

I try to keep my stove under 700F 99% of the time, but sometimes in the depths of winter on very cold night with a full charge of dry oak, that can be a challenge. If you want specific numbers for your stove, try e-mailing their tech support for something firm and in writing.

 

[woodmiser]

Hearthstone Clydesdale manual states "Do not burn over 600F for extended periods".

I will hit 700 on a hot startup to clean up the chimney and than cruise 400-600. This is actual stove top using a thermocouple/digital meter screwed into a tapped hole without the tip exposed to the firebox.

The Hearthstone inserts are actually cast iron stoves with the exception of using soapstone as the refractory.

 

[Rudyjr]

I've seen a few threads on here discussing thermometer placement etc on a kennebec stove. I've place mine in the front top as others have done. However, the manufacturer doesn't provide any temperature feedback at all!

I know someone with a jotul f600, and his manual states to put the thermometer on one of the 4 corners up top, and specifies a max temp to see at that point (corresponds to standard flue thermemeter "burn" range iirc).

What I want to know is, how hot, and where? How hot should the inside get? How hot should the flue get? And how hot should a thermometer on the top front get? Has anyone figured this out to some satisfaction?

Tom, I really do not think you need to worry unless you have a roaring fire and forget to regulate the draft. Look for some posts on this site by Cleanburnin, Brent has some good information on the Kennebec. There are some posts from Brent in the link to my installation in my signature. In three years of use we have never really come close to what I would consider an overfire on our Kennebec.