Jotul #8 crack

[Yorks]

I have a Jotul #8 that is around 7 years old. The stove seemed to end last year without any problems, but during my annual cleaning and dusting of the catalytic I found a 3 inch crack extending downward vertically from the center of the catalytic opening on the rear of the stove. It looked initially like a heavy scratch but on closer examination I saw that it went all the way through the casting. The casting at this point has a shelf teed into it and this is also cracked. The green enamel has also bubbled around the opening. It is not unusual for the temperature (taken 1/2 inch above the catalytic) to get to 1500 degrees but I am always careful to watch it closely if I think there is a chance (unusual) of it running away and I open the bypass to let it cool off. Should I be worried about the crack? What are my options for repair if you think I need to take action. Can I remove the catalytic and run the stove without it? With the catalytic removed the crack would no longer be exposed to very high temperatures as it is shielded from the main firebox. I don't burn very much these days and would prefer to keep this stove if at all possible.

Thanks.

Neil Jefferson

 

[fraxinus]

I would definitely have an experienced Jotul dealer look at it. It may be possible to replace the cracked casting. In any case, 1500 degrees is too hot at any place in a stove. Bubbling of the enamel coating would suggest even higher temperatures.

 

[begreen]

I've seen a similar crack in the earlier box stoves that had no back inner heat shield (like the 602). It does sound like it was overheated. Is the stove on a particularly tall stack? Where and how are you reading the 1500 deg. temp?

 

[Tomasacio]

I was wanting to ask the membership about my Jotul that runs away on me, when your thread caught my eye. Is the crack easily seen on the outside of the stove? Or is it in a hard to detect place? The question about the length of the flue seems relevant. If you are sucking that much extra air no wonder you're overfired. Can you close it down successfully? I would think not. I cannot close my stove enough to control the fire with the draft lever provided. Will your stove perform normally at times inspite of the crack you've found? T

 

[begreen]

Welcome Tomas. It would be good to start up a separate thread on your stove issues. There a few things we would need to check out. Post as many details about the stove and flue as you can.

 

[webbie]

I would not put too much money into a stove of that age - I think the cat Jotul 8 might be older than you mention, at least that is my memory. The cat models were sort of an in-between for Jotul, which eventually went to all non-cat versions.

If it is an internal plate, you might be able to clean it well and patch with some furnace cement or gasket (or both).

 

[Yorks]

I've seen a similar crack in the earlier box stoves that had no back inner heat shield (like the 602). It does sound like it was overheated. Is the stove on a particularly tall stack? Where and how are you reading the 1500 deg. temp?

The stainless insulated double wall stack is around 15 ft from ceiling to top hat with about 5 ft of single wall inside the room. I have a temperature probe inserted permanently above the cat in the hole Jotul provide. This is hooked up to a commercial temperature controller that I adapted to read the thermocouple. I operated with only a magnetic surface temperature thermometer on the stack for my first season, but I found it difficult to figure out when to shut the bypass (my first cat). I have to admit that watching the temperature rise can be very unnerving as it is so rapid at certain times in the burn, and until I figured out that I had to keep the wood loads down in size, caused me no end of worry. The crack is directly underneath the cat, which is in its own chamber behind the firebox.

 

[Yorks]

I would not put too much money into a stove of that age - I think the cat Jotul 8 might be older than you mention, at least that is my memory. The cat models were sort of an in-between for Jotul, which eventually went to all non-cat versions.

If it is an internal plate, you might be able to clean it well and patch with some furnace cement or gasket (or both).

I bought the stove new but I cannot find my paperwork now so the age is just my best guess. The cat is oblong, not the round type of earlier jotul's and the stove is otherwise in excellent condition. It really looks good but I don't want to put too much money into it if I can help it.

Unfortunately it is not an internal plate. The crack is directly underneath the cat access hole (letterbox) on the back of the stove. This is a separate chamber from the firebox. The crack only became visible after removing the access plate.