Black Soot on Glass and In Stove - Harmon XXV

[Dataman]

Got this stove in May and started using in Sep. Have gone thru at least 4 deep cleaning and except for noise problem we solved (screws impacting distribution fan housing) no problems.

I did deep cleaning the other day and since then I have had Black Soot in the Stove and on the glass. About 50% of the glass black. Before I never had black soot. Always light brown and not much of it.

What did I do? I cleaned the Combustion fan and other places recommended. The stove is putting out good heat (warm outside too).

I notice the flapper for the OAK (I have 3" outside air kit installed and it's working fine) is only open about 1". Swings freely.

I put magnet on the outside air port and it holds it open 100%. Seems to be burning hotter. Test will be when I come home. Any harm in keeping it open 100%?

Any suggestions? Same Pellets as before. Did not knock anything off as in plastic pipe or such. But glass soots up black in 6 hours. What did I change?

I plan on pulling off the Combustion Blower and doing cleaning again this afternoon.

This is some nasty stuff and I hope it burns off

Update: Went back an cleaned the Combustion Fan again and did the 3" Pipe. Not much ash in the pipe. Lots of black on the fan. I removed the magnet because I have to leave the house. Lowered feed rate to 2 from 3 or 4. See if that helps any. Burning North Idaho Compressed Log Pellets.

 

[Oregun]

How much pellets have you run through the stove that you needed 4 cleanings?
I would check the OAK piping in case there is a nest or obstruction in it.
Here is picture of soot on my XXV after about 2 bags of pellets.

 

[Dataman]

How much pellets have you run through the stove that you needed 4 cleanings?
I would check the OAK piping in case there is a nest or obstruction in it.
Here is picture of soot on my XXV after about 2 bags of pellets.

I have run about 3.5 tons thru it.

My glass looks about the same, but never had the black soot before until after cleaned it. I check for obstructions in OAK and Stove Pipe. Both good. Even ran brush thru.

Lowered the feed rate and same results. I guess it's "Black Face Time" for it?

I think it ran better with flap on OAK connection kept 100% open. Right now it's at most 1" the opening. Then closes when stove shuts down.

 

[Mt Bob]

Sure sounds like you have a partial restriction in the flue.But,after a certain amount of burning,ash builds up in the air wash tube,needs to be blown out with a air hose.Here is some more reading,also. https://www.hearth.com/talk/threads/xxv-airwash-reducer.82008/

 

[Dataman]

Where is the Air Wash Tube? I will hit that with air in March when done with stove and see if it helps. Stove seems fine for heat.

I am going to open up the flapper on the OAK Connector so it's not 1". I got magnet for that. More air for burning seemed to help.

 

[Mt Bob]

Well,the tube itself is inside the firebox,it feeds the slotted(normally) openings underneath the glass,but stove side.The opening in the back you usually cannot see,have to remove the OAK fitting off the back of the stove,and slightly to the left(on mine).You will need a gasket for the OAK fitting.

 

[Dataman]

It will wait until Spring then. Operation is fine except for black soot. Nasty. Running test with flapper on OAK wide open. How open is your flapper on that device in normal burn mode. Mine seems 1" at most. It closes when stove shuts down like it should to prevent smoke going back thru flex pipe.

 

[Mt Bob]

With you having to run with the flapper propped open kinda says you have other problems.

 

[Dataman]

Seems to stop the soot so far. Know in an hour. Runs fine with 1", but the black soot I did not have before deep clean. Frustrating.

 

[Mt Bob]

Idon't know your flue setup,but a partially plugged flue cap is easy to overlook.An ash pile in front of exhaust probe can stove to run strange.Bumping the probe can damage it.An incorrectly installed baffle can cause stove to burn poorly.

 

[Dataman]

I will brush out the cap tomorrow. Dark now. I did not bump the probe. These pellets have been outside under triple plastic. Dry so no wet ones. This could be normal. Just I never had the black soot before. I checked exhaust yesterday and white smoke out of chimney on startup. Then clear. Ran the brush up in the inside part today. Got some soot, but nothing to write home about really. Minor amount and no change in stove. Will figure it out. Don't like putting magnet on OAK flap really. In another hour will remove. Just not sit right with me. Gotta be something with cleaning I bet.

Thanks

Still black soot on glass after 30 min. So more air not the key here. I agree it might be exhaust. But what could I have done just cleaning combustion fan and such?

 

[Mt Bob]

I only can get softwoods,soot never looks black,until I blow it out on the snow,or get on my hands!LOL Always seems grey inside the stove.Good luck,stay warm.

 

[Dataman]

Thanks. Strange I never cared about Glass with Wood Stove. Always black soot. Just stove changed. I will run my brush and rods up the chimney. It's 8" and cap could have partial clog. Has happened before. I used to clean it monthly with Wood Stove.

Hey retired and goota find things to do!

 

[Dataman]

Sure sounds like you have a partial restriction in the flue.But,after a certain amount of burning,ash builds up in the air wash tube,needs to be blown out with a air hose.Here is some more reading,also. https://www.hearth.com/talk/threads/xxv-airwash-reducer.82008/

Did a chimney cleaning this AM. Last night more than 50% glass was sooty. It has run for 1 hour and Zero Soot. Was some buildup on top of the chimney and on the screen I have on the pipe going thru wall. That keeps little birds out and becoming SMOKE Finch Under Stainless. Really problem in spring. Like that is good place for nest.

I am going to say this soled it. Stove seems to work better too.

The screen was really coated with black soot. Nasty stuff!