Newbie questions: Jotul 602 CB

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rjm967

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Hi, everybody, I recently purchased a 1994 Jotul F 602 CB (N). I've had it installed and have spent a few days using it, and now have several questions. First, the relevant background details:

I bought it from the sole owner who said he had hardly every used it because it was built into their house in a space too small; they eventually removed it, hoping to put it into another house, but that never worked out. So as far as the previous owner tells me, it's like a new/very good-condition stove, but still very old. (It's one of those transitional models that has 602 N stamped on the front, but on the back plate says CB, so it does have the newer secondary burn feature, and the original manual is for a CB.)

Now I have it installed in a shed/cabin in southern WV that's only about 325 sq ft floor space, but does have lofted-barn style ceilings up to 9.5 ft. So there's a good amount of volume to fill. We insulated the walls and ceilings with 4-inch Rockwool and 6-inch underneath (it sits up on blocks). I'll say something below about how it works for that space, because I know that's a question many people have, and I had. But first the immediate questions:

1. The glass is loose. I thought this was because we moved it and so I repositioned it and tightened the (three out of four) screws down, but when I went to clean it today, I realized that made no difference whatsoever. I can't tighten the screws anymore, and it just slides back and forth. Even when it is positioned correctly over the glass gaskets, I can press my thumbs against it and it pushes in and out, maybe 1/8". Is this normal? Should I replace the glass gaskets? It's hard to imagine that new gaskets would eliminate the gap I'm feeling there. I even wonder whether they replaced the glass with something skinner than it should be.

1b. Like I said, there are only three out of the four screws holding the glass in (the bottom left is missing). And they are pretty stripped out. Is it possible to purchase replacements? Where?

2. Thermometer placement? I have it installed side venting straight through the wall. All the stove thermometers and guidance about them seems to be designed for placing the thermometer on a vertical single-wall stovepipe. I would like to be able to gauge creosote risk, etc., with a thermometer. So where should I put a thermometer on the actual stove, and what kinds of ideal temps am I looking for?

3. Burning at non-ideal temps? Last night it went down to 8F and my full load of hardwood at bedtime started with an interior temp of 78 . I set the air control to about 40% and six hours later the cabin temp was 52 (ideal for sleeping) and there was still a half a smoldering log and plenty of coals. This seems great, but should I be worried about creosote buildups, since it is clearly burning at very low temps?

4. Following on from 3, is creosote really bad if you can easily clean your chimney? I have a very simple setup: Selkirk through the wall T with a bottom cleanout, and then 15 vertical feet of chimney. I known creosote is bad, but if I can easily clean it, does avoiding creosote build-up need to factor into the decisions I make about how to burn the stove?

5. Open-door burning? The manual says never to burn with open door because it can overheat the stove. But I'm sitting here right now with the door having been open for about an hour, the woodbox at about 1/3 capacity of wood, and the cast iron kettle half full of water on the cooking eye isn't anywhere close to boiling. Is this really a concern? If anything, I'm worried that the stove might never get hot enough to reliably boil water or cook a steak!

In general, I'm really pleasantly surprised by how efficient this stove is; it is definitely not too much for this small, well insulated space. Also, providers of split firewood in this part of WV have no problem supplying 16" and under wood. And the hardwood is magnificent. I was splitting some of the cherry pieces for kindling, and they smell more deeply of cherry than cherries themselves! All under 20% humidity.

Thanks in advance for advice.
 
Hi, everybody, I recently purchased a 1994 Jotul F 602 CB (N). I've had it installed and have spent a few days using it, and now have several questions. First, the relevant background details:

I bought it from the sole owner who said he had hardly every used it because it was built into their house in a space too small; they eventually removed it, hoping to put it into another house, but that never worked out. So as far as the previous owner tells me, it's like a new/very good-condition stove, but still very old. (It's one of those transitional models that has 602 N stamped on the front, but on the back plate says CB, so it does have the newer secondary burn feature, and the original manual is for a CB.)

Now I have it installed in a shed/cabin in southern WV that's only about 325 sq ft floor space, but does have lofted-barn style ceilings up to 9.5 ft. So there's a good amount of volume to fill. We insulated the walls and ceilings with 4-inch Rockwool and 6-inch underneath (it sits up on blocks). I'll say something below about how it works for that space, because I know that's a question many people have, and I had. But first the immediate questions:

1. The glass is loose. I thought this was because we moved it and so I repositioned it and tightened the (three out of four) screws down, but when I went to clean it today, I realized that made no difference whatsoever. I can't tighten the screws anymore, and it just slides back and forth. Even when it is positioned correctly over the glass gaskets, I can press my thumbs against it and it pushes in and out, maybe 1/8". Is this normal? Should I replace the glass gaskets? It's hard to imagine that new gaskets would eliminate the gap I'm feeling there. I even wonder whether they replaced the glass with something skinner than it should be.

1b. Like I said, there are only three out of the four screws holding the glass in (the bottom left is missing). And they are pretty stripped out. Is it possible to purchase replacements? Where?

2. Thermometer placement? I have it installed side venting straight through the wall. All the stove thermometers and guidance about them seems to be designed for placing the thermometer on a vertical single-wall stovepipe. I would like to be able to gauge creosote risk, etc., with a thermometer. So where should I put a thermometer on the actual stove, and what kinds of ideal temps am I looking for?

3. Burning at non-ideal temps? Last night it went down to 8F and my full load of hardwood at bedtime started with an interior temp of 78 . I set the air control to about 40% and six hours later the cabin temp was 52 (ideal for sleeping) and there was still a half a smoldering log and plenty of coals. This seems great, but should I be worried about creosote buildups, since it is clearly burning at very low temps?

4. Following on from 3, is creosote really bad if you can easily clean your chimney? I have a very simple setup: Selkirk through the wall T with a bottom cleanout, and then 15 vertical feet of chimney. I known creosote is bad, but if I can easily clean it, does avoiding creosote build-up need to factor into the decisions I make about how to burn the stove?

5. Open-door burning? The manual says never to burn with open door because it can overheat the stove. But I'm sitting here right now with the door having been open for about an hour, the woodbox at about 1/3 capacity of wood, and the cast iron kettle half full of water on the cooking eye isn't anywhere close to boiling. Is this really a concern? If anything, I'm worried that the stove might never get hot enough to reliably boil water or cook a steak!

In general, I'm really pleasantly surprised by how efficient this stove is; it is definitely not too much for this small, well insulated space. Also, providers of split firewood in this part of WV have no problem supplying 16" and under wood. And the hardwood is magnificent. I was splitting some of the cherry pieces for kindling, and they smell more deeply of cherry than cherries themselves! All under 20% humidity.

Thanks in advance for advice.
Maybe the glass is loose due to the missing screw? I’d remove one and take to hardware store and see if you can find replacements. I can move my glass back and forth with my hand but it does have some resistance, it shouldn’t easily slide.

I used to run my 602 pretty much fully closed, maybe just a smidge open but I had a strong draft. No creosote problem for me. You probably just need some time and experience burning to figure out what works best for you. Keep an eye on your chimney cap and give it a sweep after your first cord of wood to see how things are going.

Are you venting out the rear or top? I’d just place the thermometer on the pipe wherever you can at least 12” from flue collar.

I never burned with an open door, just wastes heat up the flue. With the door closed my hot plate could see temps as high as 900 and it boiled water within minutes.
 
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I have a 2015 model 602. If I'm interpreting my manual's parts diagram correctly, the screws for top and bottom glass brackets are pan head M6x12 mm. Not sure if your model's door/glass is identical to mine, but to tighten it up you might also check to see if it has the thin little strip of 8mm wide flat gasket that sits on the bottom edge of the glass behind the lower bracket (if it's missing or worn out you can get a new one from Jotul dealer, part 127215 (1/8 x 1/4 flat). Also, the 3/16 round glass gasket may have compressed, creating looseness. As stated in (my) manual, at the top right and left corners of the glass, the gasket must loop over and a little ways down the inside surface of the glass. Be sure to leave both "tails" of the gasket long enough that they will extend just a little below the bottom edge of the upper bracket, and will be in contact with it, when you reinstall it. The "tails" sandwiched between the bracket and the glass are the only two points where the glass is held at the top.
 
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I have a 2015 model 602. If I'm interpreting my manual's parts diagram correctly, the screws for top and bottom glass brackets are pan head M6x12 mm. Not sure if your model's door/glass is identical to mine, but to tighten it up you might also check to see if it has the thin little strip of 8mm wide flat gasket that sits on the bottom edge of the glass behind the lower bracket (if it's missing or worn out you can get a new one from Jotul dealer, part 127215 (1/8 x 1/4 flat). Also, the 3/16 round glass gasket may have compressed, creating looseness. As stated in (my) manual, at the top right and left corners of the glass, the gasket must loop over and a little ways down the inside surface of the glass. Be sure to leave both "tails" of the gasket long enough that they will extend just a little below the bottom edge of the upper bracket, and will be in contact with it, when you reinstall it. The "tails" sandwiched between the bracket and the glass are the only two points where the glass is held at the top.
I just bought a Jotul 602 cb it was a leftover the 602 eco was not availabl and I needed a stove now as my old Jotul was on it’s last legs, I’m glad I got it, watched a video of the eco and it showed a cutaway of the burn system wow! looks like a turbo off a drag racer. I’m sure it might be better on GPH but the 602cb was 2020 approved, it seems like the eco will only take a half load of 14” splits as the turbulator on the eco takes up 1/3 of the fire box. If you want a 602 you might want to get one now.
 
@nola mike has (had?) this model and had to triage air leaks including around the glass IIRC. His had seen much more use and he rebuilt it. If you search for threads in this forum on Jotul 602 posted by member nola mike you will find several postings. Here is one of the more recent ones where he did the partial rebuild.
 
Hi, everybody, I recently purchased a 1994 Jotul F 602 CB (N). I've had it installed and have spent a few days using it, and now have several questions. First, the relevant background details:

I bought it from the sole owner who said he had hardly every used it because it was built into their house in a space too small; they eventually removed it, hoping to put it into another house, but that never worked out. So as far as the previous owner tells me, it's like a new/very good-condition stove, but still very old. (It's one of those transitional models that has 602 N stamped on the front, but on the back plate says CB, so it does have the newer secondary burn feature, and the original manual is for a CB.)

Now I have it installed in a shed/cabin in southern WV that's only about 325 sq ft floor space, but does have lofted-barn style ceilings up to 9.5 ft. So there's a good amount of volume to fill. We insulated the walls and ceilings with 4-inch Rockwool and 6-inch underneath (it sits up on blocks). I'll say something below about how it works for that space, because I know that's a question many people have, and I had. But first the immediate questions:

1. The glass is loose. I thought this was because we moved it and so I repositioned it and tightened the (three out of four) screws down, but when I went to clean it today, I realized that made no difference whatsoever. I can't tighten the screws anymore, and it just slides back and forth. Even when it is positioned correctly over the glass gaskets, I can press my thumbs against it and it pushes in and out, maybe 1/8". Is this normal? Should I replace the glass gaskets? It's hard to imagine that new gaskets would eliminate the gap I'm feeling there. I even wonder whether they replaced the glass with something skinner than it should be.
The glass is somewhat loose, but the gasket should be tight enough to prevent any leaks. The top of the glass is ungasketed to allow for non adjustable air wash down the glass. I extended the gasket a bit to give me a bit more control over primary flow.

1b. Like I said, there are only three out of the four screws holding the glass in (the bottom left is missing). And they are pretty stripped out. Is it possible to purchase replacements? Where?
Just standard metric screws. Use stainless.

2. Thermometer placement? I have it installed side venting straight through the wall. All the stove thermometers and guidance about them seems to be designed for placing the thermometer on a vertical single-wall stovepipe. I would like to be able to gauge creosote risk, etc., with a thermometer. So where should I put a thermometer on the actual stove, and what kinds of ideal temps am I looking for?
These burn hot. The cook plate can be 1-200' hotter than the rest of the stove. I use an ir thermometer, and the hottest part of the burn will be 900' on the cook plate and upper 700's at the rear corners. I've started turning down based on flame appearance rather than temps--this thing gets going so quickly that the temps lag behind. Iirc my pipe temps run about 500, but the pipe isn't easily accessible in my setup so I don't usually check it.

3. Burning at non-ideal temps? Last night it went down to 8F and my full load of hardwood at bedtime started with an interior temp of 78 . I set the air control to about 40% and six hours later the cabin temp was 52 (ideal for sleeping) and there was still a half a smoldering log and plenty of coals. This seems great, but should I be worried about creosote buildups, since it is clearly burning at very low temps?
Sounds like you have wet wood or poor draft. 40% open on mine would severely over fire. I'm usually open just a sliver. In 6 hours I'll have a few coals, that's it. I never have anything smoldering. When trying to maximize heat I will open the air up gradually as the flames lessen.

4. Following on from 3, is creosote really bad if you can easily clean your chimney? I have a very simple setup: Selkirk through the wall T with a bottom cleanout, and then 15 vertical feet of chimney. I known creosote is bad, but if I can easily clean it, does avoiding creosote build-up need to factor into the decisions I make about how to burn the stove?
If you're burning correctly/hot, it shouldn't be a concern. I get about 3-4c powder/year
5. Open-door burning? The manual says never to burn with open door because it can overheat the stove. But I'm sitting here right now with the door having been open for about an hour, the woodbox at about 1/3 capacity of wood, and the cast iron kettle half full of water on the cooking eye isn't anywhere close to boiling. Is this really a concern? If anything, I'm worried that the stove might never get hot enough to reliably boil water or cook a steak!
With the door fully open you'll have a fireplace. Inefficient, not doing much to warm. If the door is just cracked you'll over fire. You'll also get a much hotter fire with a full firebox.

In general, I'm really pleasantly surprised by how efficient this stove is; it is definitely not too much for this small, well insulated space. Also, providers of split firewood in this part of WV have no problem supplying 16" and under wood. And the hardwood is magnificent. I was splitting some of the cherry pieces for kindling, and they smell more deeply of cherry than cherries themselves! All under 20% humidity.

Thanks in advance for advice.
I'm heating a 2k sqft house with mine, uninsulated brick. 20's night/upper 30's day temps and I can keep the downstairs at 68 and the upstairs at 62 (with a bedroom door closed). 9 ft ceilings.
 
@nola mike has (had?) this model and had to triage air leaks including around the glass IIRC. His had seen much more use and he rebuilt it. If you search for threads in this forum on Jotul 602 posted by member nola mike you will find several postings. Here is one of the more recent ones where he did the partial rebuild.
Wow, that was 4 years ago. I chased glass leaks for a while, but I think that if you can't control the burn you more likely have a panel leak somewhere. When I rebuilt I found some questionable cementing, presumably from the factory. Last season had a leak on the side that I couldn't find, overfired pretty bad a couple of times and warped that manifold again. I'm going to see if it can be repaired or replaced after the season. Also the zircor panels have been a bust, they're too brittle. Likely going to have to get new cast panels for next season. The warped manifold is keeping me from getting a secondary burn (unless the air leaking around the sides is reburning, which is possible), which interestingly doesn't seem to be affecting much. Still no smoke except for the first few minutes of a cold start.