Jotul Oslo F500 ash pan door forming creosote as well as behind ash pan on back wall and inside firebox

[Jriley09]

Attached are a few pictures showing the creosote. In February I replaced ash pan door gasket when I noticed similar creosote forming. Hasn’t really fixed the problem with new gasket. Stove was purchased in December of 2019 new. I have since scraped with a screwdriver and scrubbed with wire brush. I’m wondering if anyone else has experienced this and should I be concerned or just keep scraping away at it. I’ve also begun to notice some forming around left side door near the heat plate as well as back left and right corners of stove. And even behind firebrick you can see the shine in last picture. I replaced side door gasket yesterday and scraped creosote as well it’s already reappearing. Is there something I’m missing? TIA

 

[bholler]

Attached are a few pictures showing the creosote. In February I replaced ash pan door gasket when I noticed similar creosote forming. Hasn’t really fixed the problem with new gasket. Stove was purchased in December of 2019 new. I have since scraped with a screwdriver and scrubbed with wire brush. I’m wondering if anyone else has experienced this and should I be concerned or just keep scraping away at it. I’ve also begun to notice some forming around left side door near the heat plate as well as back left and right corners of stove. And even behind firebrick you can see the shine in last picture. I replaced side door gasket yesterday and scraped creosote as well it’s already reappearing. Is there something I’m missing? TIA

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I have never seen that. Can you describe your chimney system. Moisture content of your wood and procedure for running the stove?

 

[CentralVAWoodHeat]

I had an F400 and an F600. I observed similar buildup in my ash pan area. Not sure if you should be concerned or not but I no longer own either stove.

 

[Jriley09]

I have never seen that. Can you describe your chimney system. Moisture content of your wood and procedure for running the stove?

Neither have I. Which is cause for concern in my opinion. We have a flexible 6” liner through raised fireplace covered with a steel plate covering fireplace and up through chimney with liner that is 12-15’ max. Have been using oak seasoned over a year and a half at about 12-18% moisture. Haven’t changed anything I’ve been doing with wood or fire building in past three years. Usually start small fire leaving side door cracked till about 6-700 on the flu,shut door then wait 10 mins or so before shutting primary air about 1/3- 1/2 way and then another 10-20 mins close primary till about 2/3-3/4 closed. If door isn’t cracked for beginning we have trouble getting up to temp of 6-700 if we don’t have a bed of hot coals present.

 

[Jriley09]

Is it possible to have a creosote fire(chimney fire per se) within the firebox it self?

 

[bholler]

Neither have I. Which is cause for concern in my opinion. We have a flexible 6” liner through raised fireplace covered with a steel plate covering fireplace and up through chimney with liner that is 12-15’ max. Have been using oak seasoned over a year and a half at about 12-18% moisture. Haven’t changed anything I’ve been doing with wood or fire building in past three years. Usually start small fire leaving side door cracked till about 6-700 on the flu,shut door then wait 10 mins or so before shutting primary air about 1/3- 1/2 way and then another 10-20 mins close primary till about 2/3-3/4 closed. If door isn’t cracked for beginning we have trouble getting up to temp of 6-700 if we don’t have a bed of hot coals present.

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Your chimney is on the short side especially with the horizontal run and 90. So your draft is probably a bit weak which is why the door needs cracked as well. I would check all the gaskets just to make sure they are still ok

 

[bholler]

Is it possible to have a creosote fire(chimney fire per se) within the firebox it self?

Possible yes but it's not a problem

 

[Jriley09]

Your chimney is on the short side especially with the horizontal run and 90. So your draft is probably a bit weak which is why the door needs cracked as well. I would check all the gaskets just to make sure they are still ok

Thank you. When you say check all gaskets meaning even the top griddle and stove top as well? My vermiculite baffle has a slight crack in it for the past year but I can’t imagine that has any effect on it.

 

[Jriley09]

Thank you. When you say check all gaskets meaning even the top griddle and stove top as well? My vermiculite baffle has a slight crack in it for the past year but I can’t imagine that has any effect on it.

I have done the dollar bill test on front door, ash pan door, and side door. All snug couldn’t pull dollar out except for side door I could a little, basically in the bottom right corner. 1/4 of the right side bottom and 1/4 of the bottom right side. I have seen some say it’s ok to be able to pull dollar out so long as there is resistance.

 

[bholler]

I have done the dollar bill test on front door, ash pan door, and side door. All snug couldn’t pull dollar out except for side door I could a little, basically in the bottom right corner. 1/4 of the right side bottom and 1/4 of the bottom right side. I have seen some say it’s ok to be able to pull dollar out so long as there is resistance.

Sounds good. It definitely isn't anything alarming just not typical of what I see

 

[begreen]

The ashpan door gasket can be tricky. This thread shows a similar issue.

Jotul ash pan gasket (the one not on the door) question?

Hi Everyone, I was cleaning the stove and trying to find an air leak. I think I found a it. The 3 “ pieceof gasket that is attached to the pan and not the door was falling off. Can anyone tell me how is supposed to be cemented on, or share a pic. I’ve taped it in place and stuck a flashlight in...

www.hearth.com

 

[Jriley09]

Sounds good. It definitely isn't anything alarming just not typical of what I see

Thank you for your time and advice as well.

 

[Jriley09]

The ashpan door gasket can be tricky. This thread shows a similar issue.

Jotul ash pan gasket (the one not on the door) question?

Hi Everyone, I was cleaning the stove and trying to find an air leak. I think I found a it. The 3 “ pieceof gasket that is attached to the pan and not the door was falling off. Can anyone tell me how is supposed to be cemented on, or share a pic. I’ve taped it in place and stuck a flashlight in...

www.hearth.com

Thank you. I’ll check ash pan for those gasket whips along top of ash pan mount gasket

 

[xman23]

It's a little hard to see any issues in the pictures. Yes I get the same creosote on the ash door and behind the fire bricks. It doesn't get washed by any flames. I assume you cleaned the stove down well enough to find any base cracks.

I had to go up one gasket size on the ash pan door. On the hinge side it was to loose. Hinges probably worn. So I think it was 1/4 and I went to 3/16.

Gaskets can be a little tricky. I tend to push it together a bit, as I lay it into the RTV. Just don't stretch them out. Be consistent.

 

[Jriley09]

It's a little hard to see any issues in the pictures. Yes I get the same creosote on the ash door and behind the fire bricks. It doesn't get washed by any flames. I assume you cleaned the stove down well enough to find any base cracks.

I had to go up one gasket size on the ash pan door. On the hinge side it was to loose. Hinges probably worn. So I think it was 1/4 and I went to 3/16.

Gaskets can be a little tricky. I tend to push it together a bit, as I lay it into the RTV. Just don't stretch them out. Be consistent.

I haven’t checked the bottom interior for base cracks. I forgot to mention when I was replacing gasket on left side door I took it off to do it and there was one washer on the bottom hinge pin but none on the top hinge pin. I haven’t taken food off before so I wasn’t sure if one is missing and that could help with the alignment of door? Thanks for all the help!

 

[EbS-P]

I can get creosote running down into the ashpan on a cold start with wet wood in an empty pan. Some on the door too. Usually a good hot fire with dry wood and an empty pan is all it take to clean it all back up.

 

[bladeofanduril]

Interesting thread. I was about to post a similar one. I've noticed this creosote formation on the ashpan door and some on the walls as well. This is the first season with my stove. So far, (though I may stop) I'm still using the ashpan. I'm burning majority ash, with some spruce, hickory and maple mixed it. All of it below 20% in random testing. I have an 8" flux liner running up the chimney (about 25' tall), stove is connected with a t-fitting (rear exit). I typically run the stove hot in the morning (full air, thought surface temp usually doesn't get higher than 550F), then turn it down med/med-low most of the afternoon and evening. Overnight I load it up, get it going, and then turn the air control full left or just a hair short of full left. In the morning, there are usually enough embers left to get fire going once more.

 

[Jriley09]

Thank you. When you say check all gaskets meaning even the top griddle and stove top as well? My vermiculite baffle has a slight crack in it for the past year but I can’t imagine that has any effect on it.

Another question regarding chimney height. Would I be better adding height to existing liner, or just eliminate chimney and pipe straight up from stove through roof with a double wall lined pipe and eliminate the elbows from stove into fireplace and up the chimney?

 

[Jriley09]

I can get creosote running down into the ashpan on a cold start with wet wood in an empty pan. Some on the door too. Usually a good hot fire with dry wood and an empty pan is all it take to clean it all back up.

I’ve also struggled to figure out if I like having the pan full of ash and shoveling out ash from firebox vs using the tray. I feel like I prefer leaving ash pan full but I’m wondering if that has anything to do with buildup?

 

[bladeofanduril]

I’ve also struggled to figure out if I like having the pan full of ash and shoveling out ash from firebox vs using the tray. I feel like I prefer leaving ash pan full but I’m wondering if that has anything to do with buildup?

My hypothesis is that the creosote deposits are the result of embers falling through the grate into the ashpan and smouldering there. If that's accurate, letting the ashpan fill up would sort of seal off the ash compartment with ash, and maybe reduce the likelihood of creosote forming there.

 

[Jriley09]

Interesting thread. I was about to post a similar one. I've noticed this creosote formation on the ashpan door and some on the walls as well. This is the first season with my stove. So far, (though I may stop) I'm still using the ashpan. I'm burning majority ash, with some spruce, hickory and maple mixed it. All of it below 20% in random testing. I have an 8" flux liner running up the chimney (about 25' tall), stove is connected with a t-fitting (rear exit). I typically run the stove hot in the morning (full air, thought surface temp usually doesn't get higher than 550F), then turn it down med/med-low most of the afternoon and evening. Overnight I load it up, get it going, and then turn the air control full left or just a hair short of full left. In the morning, there are usually enough embers left to get fire going once more.i

Interesting thread. I was about to post a similar one. I've noticed this creosote formation on the ashpan door and some on the walls as well. This is the first season with my stove. So far, (though I may stop) I'm still using the ashpan. I'm burning majority ash, with some spruce, hickory and maple mixed it. All of it below 20% in random testing. I have an 8" flux liner running up the chimney (about 25' tall), stove is connected with a t-fitting (rear exit). I typically run the stove hot in the morning (full air, thought surface temp usually doesn't get higher than 550F), then turn it down med/med-low most of the afternoon and evening. Overnight I load it up, get it going, and then turn the air control full left or just a hair short of full left. In the morning, there are usually enough embers left to get fire going once more.

I wondered if not using the ashpan has contributed to my “problem” but I don’t think it has with what your finding in your stove. For a while we used it but I find it more of a PIA to use and messy. Plus I feel like having the ashram full helps keep the coal bed a touch hotter/longer lasting

 

[Jriley09]

My hypothesis is that the creosote deposits are the result of embers falling through the grate into the ashpan and smouldering there. If that's accurate, letting the ashpan fill up would sort of seal off the ash compartment with ash, and maybe reduce the likelihood of creosote forming there.

Thank you. I feel that may be the case, hopefully.

 

[bladeofanduril]

I wondered if not using the ashpan has contributed to my “problem” but I don’t think it has with what your finding in your stove. For a while we used it but I find it more of a PIA to use and messy. Plus I feel like having the ashram full helps keep the coal bed a touch hotter/longer lasting

I think I will experiment with this. I'll report back...

 

[bladeofanduril]

Update: I let the ash pan fill up. I cleaned the creosote off of the ash door, and have burned the stove for about a week since. There has been no new creosote on the door. So I think this mostly proves my theory. To confirm, I'd have to empty the ash pan and burn for a bit to see if the creosote returns, but I'm fairly sure it would.

Some other observations of interest... with the pan full, it essentially seals off that whole compartment as well as the two "boost" air holes in the sides of the ash compartment. This has resulted in two noticeable changes: 1. the stove burns longer with the air control turned to low - more glowing embers left in the morning. 2. I notice more charcoal, which indicates to me a slightly less complete burn. With the boost air in play, most of what was left in the morning was light grey powdery ash.

Downside, the stove is hotter when I want to remove ash, resulting in more hot embers going into the ash bucket.

 

[begreen]

I stopped using the ashpan on the F400 halfway through the first season and let it fill up. It ran so much better that I never went back to using the ashpan.