Jotul Overfire Temp

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sabastio

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Oct 9, 2007
5
Does anyone know what the exact temperature start range is for a stove to be considered "over fire"
And what is the ideal temp to keep the stove at for most efficiency and heat output? My manual is rather vague on both subject.Thanks for all the advice...VERY MUCH APPRECIATED
 

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Cast iron stoves should not be run too much above 750 Over 800 is close to over firing.
a good safe heat productive range surface mount thermometer is 500 to 650
 
I recently spoke with a Jotul employee who said cast iron begins to break down around 900 degrees. I was questioning him regrading my new F3CB and was told even hitting this temp would not ruin your stove. Probably best not to hit that temp very often though... I find my stove loves about 575 with the main vent wide open. I have run it up to 750 when trying to "burn" the smell out of the new unit. My advise is use your best judgement for your situation. The documentation is vauge in my opinion due to the wide variety of factors at play. I think conventional wisdome says 400 - 600 is best. I know when its -10 outside and I'm trying to keep my house warm this winter I'll be cranking my little stove above 600.
 
Where is the best location for the thermometer? on the stove or in the pipe? It does not take long to hit 600 degrees
Guess I should have bought the Oslo.....Castine does not seem to do the job and its not cold yet. Guess time will tell.
Ted
 
The stove I am getting by Travis industries. xp33 elite states in user manual anything over 800F is in the over fire range and will void the warranty. this is a plate steel unit not cast.
 
Obviously manufacturers want to protect themselves and customers by keeping the temps low. The truth is that, depending on the stove model, higher temperatures often cannot be helped. If the makers were really concerned, they would be able to put governors or other devices on the stove to keep 'em low or shut them down on overfire (some early models - like the Patriot - had these!)....

The Jotul folks are telling you what is closer to the actual truth - but this can depend on many factors. I think the stove shown is a Jotul #3 - perhaps an older one. My cousin has this model, and that sucker has been hot (over 700) for years. But no doubt that constant high temp fires may craze enamels......

In a very general sense, I would say that the ideal HIGH range of temps on the top of a single wall stove would be 700-800. However, short bursts at 800-900 should not hurt properly designed black (painted) stoves.
 
So, the "Homesaver" Stove Top Therm Red lines at 475....although it goes to 750. A few log load at full damper hits or exceeds the 500 a little. I try to keep my Castine right about 500. This therm is keeping you "light" for safety concerns? I would imagine running 350 - 400 as they indicate would cause other build up problems.

How heavy has anyone load a Castine and had the temp run constant?

So what style of therm do you prefer? Brand?
 
When it gets colder outside you will probably strongly consider running it hotter. Ignore the zones on the thermometer or get one without recommended ranges. The stove wants to run between 450 and 650 degrees. An occasional foray to 700 degrees is possible without hurting the stove. If you peg the needle, you should know why and slow things down.
 
looking that the first picture mounted within the fire place opening,I have one additional observation. Free standing stoves are designed to be in open spaces
allowing free air flow around all sides of the stove pluss the brick absorbing heat and radiating it out does not seem to me an ideal setup for a free standing stove design.

let me review a personal experience with one of my computers. It was situated in a compartment in a computer desk after a while I get all kinds of error messages and it locks up I plug in my post diagnostic board and it tells me the processor is bad. but next day it runs fine for about 1/2 hour again the same pile of error messages and it freezes so I replace the processor A little time goes by and the same thing happens finally i replace the processor again but this time I remove it from the enclosed cabinet in the computer desk I never suffered problems again. The confined space did not allow enough free flowing air space. Apply this to you confined location of your stove. Did anyone think that confining air space around a stove limits reducing heat dissipation?
so what temps should you run your stove in that location I can't tell you but My guess it should run on the lower end . 750 in that location might just ruin your stove. I don't know what parameter to tell you, for a stove designed to be free standing?
 
Is that an appropriate analogy? A computer -requires- the rapid dissipation of heat away from sensitive components in order to function. This is not true of a wood stove. A wood stove actually performs better at high temps and is not threatened by staying at design temps. The effect of heat on electronics is not at all the same as heat on cast iron.

The Firelight is a close clearance stove. I can't be sure by the image but it looks like it has about 2.5x the required side clearances. As long as the stove is operated in it's designed temperature range, I don't think it's more threatened by being in the fireplace. This type of installation is quite common, especially in Europe.
 
harmerd said:
So, the "Homesaver" Stove Top Therm Red lines at 475....although it goes to 750. A few log load at full damper hits or exceeds the 500 a little. I try to keep my Castine right about 500. This therm is keeping you "light" for safety concerns? I would imagine running 350 - 400 as they indicate would cause other build up problems.

How heavy has anyone load a Castine and had the temp run constant?

So what style of therm do you prefer? Brand?

I load my Castine as full as possible. The Condor magnetic therm is on the stove top as shown in your castine manual. This therm will peg at 900*. When my stove reaches 600* after loading, I back down the air intake to 1/2, possibly more if necessary. This will keep the sove running smooth between 450- & 600* depending on species of wood and split size. This is after total Char of load and it also ensures secondary burn has kicked in.
 
You mean that the thermometer reads up to 900 degrees, but you never burn in that territory, correct? If that is the case, sounds like you are doing things correctly, though I damper down sooner. Soft maple rarely gets the stove above 550 unless I am really pushing it.

Once the stove top reaches 350-400 I damper down, but it depends on the wood I'm burning. I've found that the stove will actually get warmer and secondary burning will be better by dampering down to about half. It seems to force it to go into secondary burning.
 
Begree almost all inserts have an outer convection jacket made to dissipate heat in a confined area, some coupled with blowers. I don't know if my analogy was appropriate. I was making an observation. wondering if the one pictured has enough free flowing air around it to dissipate heat? I said I was not sure.
 
BeGreen said:
You mean that the thermometer reads up to 900 degrees, but you never burn in that territory, correct? If that is the case, sounds like you are doing things correctly, though I damper down sooner. Soft maple rarely gets the stove above 550 unless I am really pushing it.

Once the stove top reaches 350-400 I damper down, but it depends on the wood I'm burning. I've found that the stove will actually get warmer and secondary burning will be better by dampering down to about half. It seems to force it to go into secondary burning.

Correct Sir , it reads 900* but I never try burning at that range. Although, a spike now and then can happen with smaller splits.
 
Elk, drop over to Jotul UK. Take a look at the installations pictured of the F400 or MF3. This is a common application for Jotuls. The non-box stoves run cooler at the back and sides than some stove. From what I can see of sabastio's installation, it looks like there is very generous clearance around it.

I think a wood stove is more analogous to a diesel engine, it likes to be warm. Draft is better as the castiron temp becomes more uniform. FWIW, some of the older and non-blower inserts did not have a convection jacket. The old Majestic smoke dragon I pulled out of our house didn't. I thought the outer jacket is primarily to get heat into the house via convection or a blower, not protect the stove. But maybe I'm wrong. Corie, Mike what do you think?
 
for long periods, it is. If it just spikes up there because of some amazing wood or you have the entire firebox as one big mass of glowing coals, then it is probably OK.

A well designed stove should be able to take normal operation and it should take many weeks or months of over firing to degrade and destroy parts. The exceptions are coal stoves, which you could warp in a very short time - a couple days if you used them incorrectly.
 
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