Jotul Firelight 12 overheats - help?

[MaureenR]

Ever since my Jotul was brand new, it's had the problem of overheating when I loaded the box full and the catalyst was engaged. In the middle of the night, the rear box glowed red. I disengages the damper and then the front box would roar and overheat. So I stand there alternating between damper on and damper off to allow the two boxes alternately some time to cool. It scares me to use the darn stove.

The dealer said not to load so much wood in the box, which kind of defeated the purpose of having bought the larger stove so it could make it through the night.

Any ideas?

 

[begreen]

Welcome Maureen. How tall is the chimney on the stove? Have you tried adding a manual key damper in the connector pipe coming off of the stove?

 

[MaureenR]

Welcome Maureen. How tall is the chimney on the stove? Have you tried adding a manual key damper in the connector pipe coming off of the stove?

 

[MaureenR]

I have about 2' of pipe before it turns to go into the chimney. I always thought I was never supposed to use a pipe damper with this kind of stove. Are you suggesting that I not use the damper/catalyst, so the rear box won't heat up, but instead use the pipe damper to keep the front box dampered down?

 

[Bluerubi]

I just sold my firelight 12, but did have a damper in my flue to slow down the strong draft I was getting (about 40' chimney). Even without the damper I could almost choke it down to the point where it would die out once I replaced all the gaskets, so it might be time for a rebuild or inspection for air leaks.

 

[MaureenR]

I just sold my firelight 12, but did have a damper in my flue to slow down the strong draft I was getting (about 40' chimney). Even without the damper I could almost choke it down to the point where it would die out once I replaced all the gaskets, so it might be time for a rebuild or inspection for air leaks.

Thanks for all the quick replies. I don't think this is a leak problem because it has happened since the stove was brand new. Unless there was a leak straight out of the factory.

And I guess the request about the chimney height was for the chimney, not the stove pipe. My chimney is only on a one-story house, so it's about 15'. But this stove used to be in my old house, which had a 2-story chimney and the problem was worse there.

 

[Bluerubi]

Thanks for all the quick replies. I don't think this is a leak problem because it has happened since the stove was brand new. Unless there was a leak straight out of the factory.

And I guess the request about the chimney height was for the chimney, not the stove pipe. My chimney is only on a one-story house, so it's about 15'. But this stove used to be in my old house, which had a 2-story chimney and the problem was worse there.

My brand new insert had a bad door gasket that I lived with the first year because I assumed it was good. Failed the dollar bill test miserably.

 

[Ohlson35]

Thanks for all the quick replies. I don't think this is a leak problem because it has happened since the stove was brand new. Unless there was a leak straight out of the factory.

And I guess the request about the chimney height was for the chimney, not the stove pipe. My chimney is only on a one-story house, so it's about 15'. But this stove used to be in my old house, which had a 2-story chimney and the problem was worse there.

 

[Ohlson35]

Hello,what was the out come of the overheating? Same is going on here with mine..

 

[Ohlson35]

Thanks for all the quick replies. I don't think this is a leak problem because it has happened since the stove was brand new. Unless there was a leak straight out of the factory.

And I guess the request about the chimney height was for the chimney, not the stove pipe. My chimney is only on a one-story house, so it's about 15'. But this stove used to be in my old house, which had a 2-story chimney and the problem was worse there.

 

[Ohlson35]

Hello Maureen ,what was the outcome of the over firing?

 

[NHJotul]

Well, I know this is a dead thread but in case some one does come across it...

Several things I found to overheat a jotul Firelight 12.

1.) Air leaks. When you move the stove you should apply stove cement to certain parts then remember to do a break in with some small fires. also, gaskets can leak and even from a factory.

2.) Small splits of wood will overheat the Catalyst, combine that with a strong draft and I can imagine you will be having the issue described above.

3.) If you want to run a full load of wood, according the the manual, you should have a least 3" of coals which is close to the glass on the doors. With a typical catalyst, big dry splits, and a large bed of coals without an excessive draft, then spiking into the 1800 degrees can and will happen.

However... and I intend to create a thread on this one soon. I decided to use a Clearskies Catalyst. Reticulated Ceramic foam catalyst. Its only day one but I decided to treat it like a beast of burden and give it hell to see what it can handle.

So far, I started of with some small pieces and one of them was hissing loud enough that I could hear it with the door shut. I knew I had a few pieces I mixed in with my covered wood and apparently I found one. I figured lets give this thing a real world, I don't have time to babysit, run.

15 minutes from kindling to small fire with a couple small sticks thrown on and I flipped the bypass.

at first it climbed to 600 hundred quicker then I am use to with a condar or the 20 year old OEM. Also i noticed that switching the bypass didn't seem to effect the flame either.

The clearSkies are only an inch thick so I guess it make sense. It seems to let the jotul breath much easier when I engage the bypass.

Went out side and saw a ton of white steam dissipating to nothing 6 feet or so away and the catalyst was running 800.

Loaded it up to the max, flipped it back then put the damper to the lowest setting and after an hour decided it was fine and left.

The digital catalyst monitor beeps when it gets to 600 or 1400 hundred degrees. I guess while I was gone it hit 1400, according to my wife but she left it and it dropped back down.

So, This left a nice big bed of coals. Loaded it again to the max with large White Ash splits and a couple Oak pieces on top and so far she is running 1200 and the damper is all the way closed and all I can see is a red glow at the bottom.

With the dry wood, all I see is heat rising from the chimney so it would seem to be burning up all the smoke.

Looking at the catalyst, it seems to be able to lose heat quicker. When i disengage it, the temp drops rapidly down to under 250 in less than a minute from 1200. The honeycomb catalyst held heat very well in comparison.

Like I said, So far, and for only $99, this catalyst is amazing and takes off a 380 degrees and seems to also get there quicker.
I will write a post on this just want to give it a month and have a fire cat I will have to alter if this one fails for any reason but so far one other person on here has used it and they seem to last him three years before he gets a new one. I have a catalyst thermostat so I will be keeping an eye on how this catalyst works out.

Other people have complained that these cats run cooler then get clogged. I will agree they run cooler, and anyone who has used a Jotul 12 with the small cat they use, knows cooler running catalyst is way better then one that is prone to overheating.

 

[Ashful]

Interesting. I have cooked more combustors in Jotul 12’s, than perhaps anyone on this forum. In the case of Condar and Applied Ceramics ceramic cats, I never had issues with the combustor element, it was always the insulation wrap and steel can around the combustor, which distorted from heat.

I’m surprised anyone is having trouble with cat clogging in a Jotul 12, though. The one good thing you could say about the downdraft design is that all ash tends to fall out of the air stream, as it has to turn 180 degrees and go back up thru the combustor, on its way to the outlet.

 

[NHJotul]

Interesting. I have cooked more combustors in Jotul 12’s, than perhaps anyone on this forum. In the case of Condar and Applied Ceramics ceramic cats, I never had issues with the combustor element, it was always the insulation wrap and steel can around the combustor, which distorted from heat.

I’m surprised anyone is having trouble with cat clogging in a Jotul 12, though. The one good thing you could say about the downdraft design is that all ash tends to fall out of the air stream, as it has to turn 180 degrees and go back up thru the combustor, on its way to the outlet.

The trouble was more associated with the undersized cat getting wayyyyyy too hot esp if you load the stove to the top.

I have read mostly all your post and even looked into the ashford 30 but didn’t like the ash door vs grates. I am a little too lazy to empty my ash bin as it stands I would be annoyed by the lack of and having to burn my hands or wear gloves and move around coals trying to get the ash out. Other than that I think it looks like a great stove!! Like how they designed it around the cat, also the stew inner housing for durability yet still looks nice. Only gripe is the ash door being the way to remove ashes.



So far I have been loading the jotul to the max and letting the stove pipe get to 350 then I flip it over and the clear skies catalyst burns around 1200 to 600 depending. For the First Time I can run it so choked down that I cannot are through the windows and the cat has only gone as high as 1400.

So clearSkies cats seem to be a great choice for this stove!!

The only question I have is longevity! NHcpa says he changing his every three years. He doesn’t have a cat thermometer but he seems to have no problems with it.

I don’t know if you sold your jotul’s yet but if you haven’t and have another use for them try out the clearSkies cat. $99 is even better, and the stove seems to breath really good with this catalyst.

 

[Ashful]

The trouble was more associated with the undersized cat getting wayyyyyy too hot esp if you load the stove to the top.

I have read mostly all your post and even looked into the ashford 30 but didn’t like the ash door vs grates. I am a little too lazy to empty my ash bin as it stands I would be annoyed by the lack of and having to burn my hands or wear gloves and move around coals trying to get the ash out. Other than that I think it looks like a great stove!! Like how they designed it around the cat, also the stew inner housing for durability yet still looks nice. Only gripe is the ash door being the way to remove ashes.



So far I have been loading the jotul to the max and letting the stove pipe get to 350 then I flip it over and the clear skies catalyst burns around 1200 to 600 depending. For the First Time I can run it so choked down that I cannot are through the windows and the cat has only gone as high as 1400.

So clearSkies cats seem to be a great choice for this stove!!

The only question I have is longevity! NHcpa says he changing his every three years. He doesn’t have a cat thermometer but he seems to have no problems with it.

I don’t know if you sold your jotul’s yet but if you haven’t and have another use for them try out the clearSkies cat. $99 is even better, and the stove seems to breath really good with this catalyst.

Cool. If you can keep that cat under 1700F, you’re in good shape. I had mine get so hot on a few occasions, that the back shell of the stove began to glow. I don’t know how hot they’d get, as my meter would stop reading around 2200F, I just know I exceeded that number. Way too hot.

That statement about them overheating because the combustor is too small is a theory I proposed, at the time. I honestly don’t know if it’s correct, but it seems to make sense. If you look at the combustor cross section of any similarly-sized modern BK or Woodstock, they’re about double that of the Firelight 12.

Then the question is, what is it about the ClearSkies combustor, that keeps it from getting so hot? Is it just the height? Is it tricking you, as your probe is now an inch farther from the exhaust face of the combustor? Very interesting find, we just need to sort it out, now.

On longevity, in my opinion, a 3-year replacement cycle is very acceptable. Especially at $99/combustor, you’re still saving a ton of money over most other options, no matter how you slice it. I see numbers of 10,000 - 15,000 hours batted around, as the typical lifetime of a combustor.

 

[NHJotul]

Cool. If you can keep that cat under 1700F, you’re in good shape. I had mine get so hot on a few occasions, that the back shell of the stove began to glow. I don’t know how hot they’d get, as my meter would stop reading around 2200F, I just know I exceeded that number. Way too hot.

That statement about them overheating because the combustor is too small is a theory I proposed, at the time. I honestly don’t know if it’s correct, but it seems to make sense. If you look at the combustor cross section of any similarly-sized modern BK or Woodstock, they’re about double that of the Firelight 12.

Then the question is, what is it about the ClearSkies combustor, that keeps it from getting so hot? Is it just the height? Is it tricking you, as your probe is now an inch farther from the exhaust face of the combustor? Very interesting find, we just need to sort it out, now.

On longevity, in my opinion, a 3-year replacement cycle is very acceptable. Especially at $99/combustor, you’re still saving a ton of money over most other options, no matter how you slice it. I see numbers of 10,000 - 15,000 hours batted around, as the typical lifetime of a combustor.

I think you are accurate about the combustor size. Also could be because of newer technology and maybe adding more precious metals to improve combustor tech might also be plausible.

I’m not sure how much the inch matters. 1400 is the max I hit so far it seems like it burns around 1200 max and stays between there and 800. When the temp reaches 400 it starts to rise fast. According to the manufacturer they light up at 380 and don’t mind contact with flame and also state that flame contact can help clean them.

I looked into them and who they claim to get their ceramic foam. They don’t state a max temp but from what I found it looks like they use the type made for steel mills to clean up the exhaust. Max temp is 3,200. I went by looks. The one that has a yellow tint to it looks identical however the bath could of added the yellow hew from the ghost white.

As for clogging. I read a post where someone tried a clearskies in a BK. (BKVP Stated to never use one in a bk stove.) The guy said it ran too cold and clogged. That and NHcpa mentioned this catalyst in that post about catalyst.
I ordered a fire cat in case this one didn’t work out and planed to modify it if need be. I think I may be selling it but it’s only day 2 so I won’t rush it.

I think it runs cooler because of the design and the ease at which they allow exhaust to flow. No visable change in fire intensity when I flip the bypass to the catalyst. That was a very pleasant surprise.

I will also add that watching the catalyst temp shoot up around 450ish leads me to believe that the temp if anything reads a little hotter than the actuall temp. So far I have done everything I could not get away with before with normal cats. A wet stick of wood, flipping to catalyst with a small fire and 350 exhaust pipe temp. Been very hard on it so I know what I can get away with.

If I want to keep it around 1200 degrees all I need is a large bed of coals and it doesn’t seem to go above that temp. If I have some coals from kindeling and one wet stick of wood. It runs cooler around 800, but when the wood is dry it can spike to 1400 and that was fully loaded. That was impressive for this woodstove So far I have nothing but praise and time will tell whether or not I promote it any further.

 

[NHJotul]

Before I forget I will add one last thing. I have a 15’ chimney 6”X10” flue. Not much of a draw which means when I load it some smoke comes out of the top unless I have nothing but coals and I load fast. So normally flipping the bypass meant the fire would die down a bit. This catalyst really allows for little to no perceivable restriction yet the flow 12” from the stove still stays at 225 degrees unless the catalyst gets up to 1200 to 1300 then the pipe will be about 350 every time.

 

[Ashful]

Damn, this sounds good, NHJotul. Makes me wish I discovered them several years ago, which would have saved me some frustration and sleepless nights. Keep us posted!

 

[NHJotul]

Damn, this sounds good, NHJotul. Makes me wish I discovered them several years ago, which would have saved me some frustration and sleepless nights. Keep us posted!

I am going to create a thread soon. I will tag you in it.