Jotul F55 v2 fire control question thanks

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

daoledaole

New Member
Jan 22, 2025
48
NY
the air shutter all the left but the fire still strong as the picture, is it normal? Thanks. temp is 500
 

Attachments

  • [Hearth.com] Jotul F55 v2 fire control question thanks
    IMG_2983.webp
    166.5 KB · Views: 21
500 stove top temp? It’ll take some trial and error learning a new stove. I prefer to watch the flue temps when dialing in a burn they react faster than stove top temps.
 
How long do you wait before turning it down? I have found with good wood I need to be aggressive in cutting air or it gets away from me.
It's kiln dried wood but I didn't make the air shutter "all the way left" once added, because I worried the creosote built if close air shutter soon
 
It's kiln dried wood but I didn't make the air shutter "all the way left" once added, because I worried the creosote built if close air shutter soon
If you have good dry wood I would look into a flue thermometer, you may find it gets plenty hot quick and you can turn down in stages without creosote. Stove top is always slow to catch up.
 

Great tips in this thread!
 
  • Like
Reactions: daoledaole

Great tips in this thread!
Reading……
 
It's kiln dried wood but I didn't make the air shutter "all the way left" once added, because I worried the creosote built if close air shutter soon
It looks pretty normal. Closing the air sooner will tame it a bit. If the wood is dry, creosote concerns will be less unless the flue system presents too much cooling. A flue thermometer will help in guidance, with a digital probe being the best option.
 
It looks pretty normal. Closing the air sooner will tame it a bit. If the wood is dry, creosote concerns will be less unless the flue system presents too much cooling. A flue thermometer will help in guidance, with a digital probe being the best option.
Received.
If the wood is kiln-dried but still produces smoke at the beginning of the burn, does that smoke create creosote or soot?
A thin, dust-like layer—would that be considered soot? Is soot as dangerous as creosote?
Thank you
 
There will be smoke in any stove until the firebox, and/or cat, gets up to temperature. There will definitely be some soot and ash buildup over time. That's non volatile and quite different from creosote buildup.

The flue system design can affect creosote buildup. Describe the flue system on the stove. Is it interior, straight-up, and through the roof? Or does it connect to an exterior (brick or metal) chimney? How tall is it in total?
 
There will be smoke in any stove until the firebox, and/or cat, gets up to temperature. There will definitely be some soot and ash buildup over time. That's non volatile and quite different from creosote buildup.

The flue system design can affect creosote buildup. Describe the flue system on the stove. Is it interior, straight-up, and through the roof? Or does it connect to an exterior (brick or metal) chimney? How tall is it in total?
As shown in the picture: the chimney runs inside a chase enclosure, with approximately 27 feet of ICC-Excel chimney pipe. The wood stove’s double-wall black pipe first rises vertically for about 4 feet, then goes into the wall and connects to the chimney, which runs vertically inside the chase.

Additionally, I have two questions:
  1. The first video was taken at 6:25 PM. At that time, there was already a layer of coals, and the stove top thermometer showed a temperature of 300°F. Four logs were added at that point. The second video was taken at 7:15 PM, when the stove top thermometer reached 500°F, and the temperature began to gradually drop afterward. In both videos, would the visible flames be considered secondary combustion?
  2. When there are only 3 or 4 logs in the firebox, even if there’s no visible smoke through the glass, the stove top thermometer still shows below 400°F—within the “creosote” zone. Is that because there’s simply not enough wood, so the total heat output is too low to reach a higher temperature, and therefore this situation doesn’t actually produce creosote? If that’s the case, then how can I correctly use the thermometer’s needle position to determine whether I’m burning cleanly enough to avoid creosote?
 

Attachments

  • [Hearth.com] Jotul F55 v2 fire control question thanks
    IMG_2992.webp
    117.2 KB · Views: 13
  • [Hearth.com] Jotul F55 v2 fire control question thanks
    IMG_2942.webp
    257.2 KB · Views: 12
  • IMG_2988.MOV
    4.3 MB
  • IMG_2991.MOV
    5.9 MB
Stove top thermometers aren't all that helpful. The mass of the stove body can take a while to heat up. What is important is the combustion temperatuere in the firebox which you can't easily read. It has to be above 1000º for secondary combustion to take place. For this reason, I rarely look at the stove top temperature, it's often too far behind what is happening with the fire - a lagging indicator. The best option for knowing how the fire is burning is visual and by the flue gas temperature. Visually, your fires look great. The second fire is hotter as indicated by the clearer, blue flames.

With 27ft of flue, the draft will be strong when it's cold outside. The chase will help keep the flue gases a bit warmer which in turn will help keep creosote buildup down. Creosote starts forming as a result of condensing smoke when the flue gas temp drops below about 225º. Dry wood burns hotter and will help prevent too cool flue gases. Again, a good flue thermometer will help track what is going on with the fire and the flue. A digital thermometer will provide real-time feedback.

This thread illustrates the stages of the fire. Note how far the stove top temp lags behind the flue temp.
 
Last edited:
Stove top thermometers aren't all that helpful. The mass of the stove body can take a while to heat up. What is important is the combustion temperatuere in the firebox which you can't easily read. It has to be above 1000º for secondary combustion to take place. For this reason, I rarely look at the stove top temperature, it's often too far behind what is happening with the fire - a lagging indicator. The best option for knowing how the fire is burning is visual and by the flue gas temperature. Visually, your fires look great. The second fire is hotter as indicated by the clearer, blue flames.
By the way, I have one more question: this brand new stove was installed last week, and I live in Orange County, New York. Next week, the daytime average temperature will rise to 50°F, so I might only burn occasionally in the mornings and evenings. In that case, do I still need to do a chimney cleaning this year, or can I wait until next spring?
 
It will likely be ok to wait but this will depend entirely on the wood burned next fall/winter. A load of poorly seasoned wood can gum up a chimney in a couple of weeks' burning. It's a good idea to clean after each cord burned while getting familiar with a new stove and wood supply.
 
It will likely be ok to wait but this will depend entirely on the wood burned next fall/winter. A load of poorly seasoned wood can gum up a chimney in a couple of weeks' burning. It's a good idea to clean after each cord burned while getting familiar with a new stove and wood supply.
Thank you so much for your advice! I’ll keep it in mind!