Jotul F500 V1 Oslo smoking issues after maintenance

[BruiserCT]

I moved into a house with a Jotul F500 V1 Oslo stove in June 2020. It was original to the house and started service around 2003. We have been burning wood (about 3 cords/yr) "fine" with annual chimney sweeps. All the stove behavior was expected and I was able to use it without issue. This year I decided to replace the air chamber, baffle, blanket, cracked side panel, and new/worn gaskets from upgrades. Getting into the season the stove has not been burning well at all. I have narrowed it down to starving for air. At one point experienced severe backpuffing. Interesting to watch. I first thought it was a back pressure issue. I have opened windows with no luck. You can tell the fire is banking and when I open the side door I get rolling smoke unless the fire is ripping. Even then seems unstable.

Before I have the chimney tech to come out again to see if there is some blockage, odd since it just was cleaned before season I would like to rule out other things. One item comes to mind is the previous baffle was so warped and split it did not do much. Maybe the other older gaskets were making up for the lack of intake airflow.

Wood I am burning is well seasoned and very dry.

Video of "hot burn" - https://photos.app.goo.gl/DGLNKqodiziwV5569

Any personal experience or ideas?

Thanks!

 

[Wisco Shepherd]

Before I have the chimney tech to come out again to see if there
Wood I am burning is well seasoned and very dry.

What's the moisture % reading on fresh split face of wood at room temperature?

It sounds like the repairs you made were definitely needed but if all of those gaskets and cracks were there it was likely letting in a fair amount of air into the firebox. You did the right thing sealing it up but now if the stove is burning marginal wood it does not have extra air to make up for it and keep burning clean.

There are other things to look at after ruling the first stuff out but when I hear hoofbeats I look for horses not zebras.

 

[kborndale]

Temps haven't been that cold yet so that is one factor, warm temps weaken your draft, add that with your new gaskets and you may have the problem. Are you burning at the same settings you were last winter? You may need to burn at a higher air setting.

 

[BruiserCT]

Temps haven't been that cold yet so that is one factor, warm temps weaken your draft, add that with your new gaskets and you may have the problem. Are you burning at the same settings you were last winter? You may need to burn at a higher air setting.

What's the moisture % reading on fresh split face of wood at room temperature?

It sounds like the repairs you made were definitely needed but if all of those gaskets and cracks were there it was likely letting in a fair amount of air into the firebox. You did the right thing sealing it up but now if the stove is burning marginal wood it does not have extra air to make up for it and keep burning clean.

There are other things to look at after ruling the first stuff out but when I hear hoofbeats I look for horses not zebras.

Right now I am burning the extra wood I had from last year. I just ordered a hydrometer from Amazon, I have been pretty good estimating. However, it is a good tool to have and will arrive tomorrow.

 

[BruiserCT]

Temps haven't been that cold yet so that is one factor, warm temps weaken your draft, add that with your new gaskets and you may have the problem. Are you burning at the same settings you were last winter? You may need to burn at a higher air setting.

One of my burns it was a bit warm out so I did take that into consideration. Last night we were down to 35 degrees and typically when I crack the side door to load the air rushing up the chimney, you hear it rushing. I am noticing I have the air intake open a lot more now and it does help.

 

[EbS-P]

Any modifications made to your house since last season?

I noticed a big difference in burn rate after fixing a small leak in the ash pan and and air sealing the big holes in my home.

 

[BruiserCT]

Any modifications made to your house since last season?

I noticed a big difference in burn rate after fixing a small leak in the ash pan and and air sealing the big holes in my home.

Nothing has changed in the home, it is newer and does hold temps so little to no drafts. Thanks.

 

[Ctwoodtick]

The moisture readings on a fresh split will be interesting to see. Looking for 20 or below. Let us know when the meter comes in. Split a log or 2 and then measure. Sounds like you will be warm this winter one way or other.

 

[BruiserCT]

The moisture readings on a fresh split will be interesting to see. Looking for 20 or below. Let us know when the meter comes in. Split a log or 2 and then measure. Sounds like you will be warm this winter one way or other.

I cleaned it out and again tonight no luck. Fire will start, then just low burn, open side door and smoke billowing out. 44 degrees outside.

Tested the wood and all the pieces were under 10% moisture.

 

[stoveliker]

Under 10% is not possible in CT. Best you can get is about 13-14%. Look for equilibrium moisture content tables in different climates.

You likely measured on the surface rather than resplitting a piece of wood to measure parallel to the grain on the inside of a split.

 

[BruiserCT]

Under 10% is not possible in CT. Best you can get is about 13-14%. Look for equilibrium moisture content tables in different climates.

You likely measured on the surface rather than resplitting a piece of wood to measure parallel to the grain on the inside of a split.

Note this beech wood was split last year and was sitting in the garage for winter/spring/summer. I did the readings from the end and corrected it and getting 10-11%. See photos.

 

[stoveliker]

1. Your pins are not at all far enough into the wood. Having them this way the contact resistance is far higher, making the reading artificially lower. The pins should be completely into the wood, not touching it as here.

2. Did you split these pieces right before you measured them, and then measured on the freshly exposed surface? I.e. what I see here was deep inside the split 5 minutes ago?

Measuring on the outside will get one results like this.

3. If the garage is unheated, it's more likely to be more humid than outside.
Here you can find equilibrium moisture content outdoors

https://www.fpl.fs.usda.gov/documnts/fplrn/fplrn268.pdf

If your garage is heated etc. then 10% is possible (see lumber moisture content in homes)

 

[stoveliker]

But the good news is that it is likely under 20%, so perfect for burning!

 

[EbS-P]

Let’s go back to basics F500 v1 (I can’t find the manual) didn’t have a cast iron baffle? Is that what you replaced? Did the blanket go back in the correct position? What is the air chamber?

Is this like my F400 where the side burn plates make the channel for the secondary air to the baffle. I think these need sealed with stove cement. (I could be wrong). Did you use stove cement?

 

[stovelark]

The original F500 had two cast iron baffles that fit together, with insulating blanket on top. Those sat on top of the secondary air channel (cast manifolds, stainless tubes for secondary burn). It was changed out to the ceramic baffle with blanket on top. This problem sounds like wood that is not dry enough, if all work was done correctly. Will stove burn at normal (400-600) stove top temps? At that point, the air control is typically 1/4 open. Having had an Oslo for years, my stove was totally different in ease to run below 30 degrees, as opposed to higher temps. Do not make it go by opening ashpan door! Let side door being cracked open (but on latch) if needed for extra air to get it up and running. 465 lbs of cast iron packs a heat wallop, but does take a while to get going. Good luck, stay warm, 31 degrees at my house this morning...

 

[xman23]

Is there a screen on your cap? It's the first thing to look at when the draft changes. Bottom up cleaning doesn't clean the screen.

 

[BruiserCT]

I moved into a house with a Jotul F500 V1 Oslo stove in June 2020. It was original to the house and started service around 2003. We have been burning wood (about 3 cords/yr) "fine" with annual chimney sweeps. All the stove behavior was expected and I was able to use it without issue. This year I decided to replace the air chamber, baffle, blanket, cracked side panel, and new/worn gaskets from upgrades. Getting into the season the stove has not been burning well at all. I have narrowed it down to starving for air. At one point experienced severe backpuffing. Interesting to watch. I first thought it was a back pressure issue. I have opened windows with no luck. You can tell the fire is banking and when I open the side door I get rolling smoke unless the fire is ripping. Even then seems unstable.

Before I have the chimney tech to come out again to see if there is some blockage, odd since it just was cleaned before season I would like to rule out other things. One item comes to mind is the previous baffle was so warped and split it did not do much. Maybe the other older gaskets were making up for the lack of intake airflow.

Wood I am burning is well seasoned and very dry.

Video of "hot burn" - https://photos.app.goo.gl/DGLNKqodiziwV5569

Any personal experience or ideas?

Thanks!

SOLVED:

First of all, thanks for everyone for their helpful comments. I still learned a couple of tips and tricks along the way.

I had the chimney tech come out again and he was concerned there was something with the cap. He installed it in 2009 so it should be in good shape, but he has seen obstructions mostly due to bee nests. Due to the slope of my roof and the height of the chimney itself he was not excited to get up on the roof at first. He was able to do a visual inspection from the ground and the cap looked ok. He came in and really gave it a good brushing knocking the cap to ensure it was all the way up. Expecting to have chunks of creosote raining down we had some powder and a wad of material that looked like a squirrel tail in shape and color. Once he got a 1/4 of a 5 gallon pail of ash down we had a nice draft at the elbow. We did some test burns with newspaper to confirm a good draft. That evening when it got down to 50 I started a proper fire and it ran as I would expect.

Hope my experience helps others when troubleshooting.

 

[stoveliker]

This is why a lot of folks sweep their flue before burning. To get rid of what collected during the summer.
With a soot eater or similar you can do that yourself from the inside up.

Still good to get a professional to sweep after burning season for a professional eye, insurance purposes, etc.

 

[BruiserCT]

This is why a lot of folks sweep their flue before burning. To get rid of what collected during the summer.
With a soot eater or similar you can do that yourself from the inside up.

Still good to get a professional to sweep after burning season for a professional eye, insurance purposes, etc.

I typically have him do the cleaning a month or two before burning season. Which he did this year. So I am not sure what happened, he only charged me $50 cash and came out on a Sunday since he was booked until January. Great guy and I give him credit for doing that.