Ash in hot air output with Harman Accentra

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Matt927

New Member
Dec 29, 2017
3
new hampshire
I recently installed a 2008 Harman Accentra insert. I followed the manufacturer's instruction, installing a chimney liner, and sealing the damper with sheet metal and rock insulation. I wrapped the bottom portion of the flex tubing with ceramic insulation. The pellet stove seems to work well, except after some time I get some irritation in my throat. I suspect there's ash/exhaust getting into the hot air output. It's a very small leak since I can't smell smoke(except during for a couple seconds during startup). My CO monitor doesn't register any CO on it's digital display. I noticed the decorative grate on the door where the air comes out had a light layer of ash. The hot air exhaust also had some light streaks of ash. The door gasket seemed a bit mashed up, so I replaced it. Now the door seems to push more firmly against the gasket when I latch it closed. Nevertheless I continue to develop irritation in my throat about 2 hours after the stove has started. My wife claims she doesn't notice anything. I cleaned all the ash streaks in the decorative grate. I ran the stove for a couple more hours and reexamined the door. I found a couple specs of ash. Again, I think a small amount of ash is getting into the hot air stream. I have no idea how to fix this issue. I'm worried the heat exchanger may have a small crack in it. I removed the compass plate, and the two other plates next to the burn pot to inspect, but have trouble seeing much. I honestly haven't cleaned the stove, but I'm not sure if a good cleaning would help this problem.

Any thoughts?
 
First thing that comes to mind is the dry air the stove produces. The humidity in my house is between 20 and 30. Best I could ever do with a dehumidifier running 27/7 is 50% . You may be more sensitive to dry air than the wife

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The room blower may be sucking in ash that is leaking from behind the stove.
 
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I think heat seeker has the right idea. A very small leak in the exhaust piping would be sucked up and blown through the heat exchanger. I would look for a leak in your exhaust especially if you're smelling a little smoke at start up.
Ron
 
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I'll second zrock and say it's a reaction to the dry air. I know it's a problem for me.
 
How do you explain the streaks of ash?
 
I'm not convinced its the dry air. I use force hot air propane otherwise and don't get the same reaction.

I pulled the stove out again this morning. I used high temp and regular metal tape to seal up the sheetmetal against the flue opening and it seems to be holding up. I've been ignoring the gasket on the exhaust outlet(pictured below). There are a couple flip latches which pull the stove up against the stationary frame which holds the stainless exhaust pipe. This gasket provides the seal between the stove exhaust and that stationary frame. The gasket looks a bit worn, but I don't know if it's past useful life. These gaskets cost almost $50 online so I rather not change it unless its necessary.

20171230_072846.jpg
 
I'm not convinced its the dry air. I use force hot air propane otherwise and don't get the same reaction.

I pulled the stove out again this morning. I used high temp and regular metal tape to seal up the sheetmetal against the flue opening and it seems to be holding up. I've been ignoring the gasket on the exhaust outlet(pictured below). There are a couple flip latches which pull the stove up against the stationary frame which holds the stainless exhaust pipe. This gasket provides the seal between the stove exhaust and that stationary frame. The gasket looks a bit worn, but I don't know if it's past useful life. These gaskets cost almost $50 online so I rather not change it unless its necessary.

View attachment 219166

I would say that gasket is shot, it’s almost flat at the bottom. Did you run the liner all the way to the top of your chimney?


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I would run a bead of RTV silicone on the mating surface & see if it'll seal better
for ya when it's reassembled...
Can't hurt & if the symptoms stop, you'll know that the gasket was the issue.
 
Looks to me the gasket being dark on the one side would mean its leaking.. I would seal it like mentioned above..
 
Thanks for all the suggestions. I replaced the gasket today($30 at my local stove shop). Stove has been running for the last 6 hours and no symptoms. I think it's solved. I was worried at startup, still smelled smoke. The smell went away quickly and never developed the irritation in my throat. Yeah, the house is very dry now. I'll have to invest in a good humidifier.

Thanks again.
 
Glad you got it fixed! Thanks for the feedback!
 
thanks for the update hope it's solved.