FPX44 or other flue exhaust soot issues

[ironmanco]

We have an FPX44 and have been noticing that we get pieces of soot (film-like) that come out of the flue and blow around. They not solid enough to pick up but when you try the pretty much just disintegrate in your hand. the flue is properly capped and screened. Not sure what this is from. We burn a mix between pine and local hardwoods and typically burn in the 800f range with sometimes bumping up to the 1000f range. I do also damper it down for slower burns.

Any ideas?

 

[ironmanco]

We have an FPX44 and have been noticing that we get pieces of soot (film-like) that come out of the flue and blow around. They not solid enough to pick up but when you try the pretty much just disintegrate in your hand. the flue is properly capped and screened. Not sure what this is from. We burn a mix between pine and local hardwoods and typically burn in the 800f range with sometimes bumping up to the 1000f range. I do also damper it down for slower burns.

Any ideas?

Reviving this thread. I'm still having this issue. Here are a few images of what I'm seeing. It's pretty widespread. Note that this is more like a film and there are hundreds of these all over. Some are rather large maybe 1-2" across while most are smaller "flakes". I'm burning all seasoned hardwood so not quite sure what's going on.

 

[kborndale]

How do you determine that your wood is "seasoned"? Those temps are also rather high, where are you taking them?

 

[ironmanco]

How do you determine that your wood is "seasoned"? Those temps are also rather high, where are you taking them?

Moisture meter mostly measuring <12%. Those temps are when I'm running it wide open from the cat thermometer integrated in the unit. I would say it runs typically in the 500-700 range most of the time depending on the amount of wood in the box.

 

[mpaul]

Is the Apex 44 a cat or tube stove? If a cat stove I’d say those temps are too low. You should be running closer to 1,000 - 1300 degrees.
If you’re running at 500-700 temps with the stove wide open I’d say your wood is still wet.

 

[ironmanco]

Is the Apex 44 a cat or tube stove? If a cat stove I’d say those temps are too low. You should be running closer to 1,000 - 1300 degrees.
If you’re running at 500-700 temps with the stove wide open I’d say your wood is still wet.

I actually spoke to one of the tech's at Travis and they said the same. Tho I can't get that to run regularly at 1000-1300 more like 700-900. My wood is definitely not wet - in fact it's super dry (split and confirmed). Running it wide open seems to reduce this but there are still times when it runs below or around the 700 mark and that is with a fully loaded firebox. I've confirmed that the "soot" that I'm seeing is creosote flakes blowing off the cap/pipe.

So, I guess I'll continue to burn it at hot as possible, which does seem to reduce the incidence of this issue but even then, I sometimes see this issue.

 

[mpaul]

I know I had to run it wide open to get 700-800 temps until I got my wood supply to the three year seasoned mark. Now I cruise at 1200 with the stove throttled down to 5% - 10% air and get much longer burn times.
If your wood is three years old then the next thing to consider is your draft. How tall is your chimney?

 

[ironmanco]

Ok - another update. Talked to the Travis folks again and found out that there is a gasket that surrounds the combustor that typically needs to be replaced at least every 4-5 years (maybe more often depending on use). Looking at mine there are at least 1/4" gaps between the combustor and the frame. I ordered a new set of gaskets/seals and will redo it this weekend and have another fire. I'm also planning on cleaning the firebox to kind of start with a clean slate so to speak.

We believe that when in the bypass position (cat engaged) uncombusted material is making it's way past the cat and causing this.

On a side note - I have been running it with the air damper wide open (full air) and still only get temps in the 700-800. I'm interested to see if the above changes this.

 

[mpaul]

Should be interesting to see if this resolves your issue. You need a good seal around the cat to force the smoke through. Let us know the outcome.