P43 high flame

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mcnajason

New Member
Jan 3, 2021
2
Ottawa, Canada
Hi folks, This is my second year burning with my Harman P43. I'm having a issue with a high flame, and after 5-6 hours of burning a black/ sooted up glass. I'm an automotive mechanic by trade, diagnosing and complicated disassembly/reassembly are a part of my everyday life, But I am new to pellet stoves and stumped here. I've had a "pro" take a look at my stove. He stated that it was my air inlet ( a 3 inch fresh air hose ). He stated that he's never seen one installed on a Canadian stove and its only code in the US. I've since completely disconnected the hose at the back of my P43 stove. Same issue. ( Thanks for the $200 bill). The flame looks very high, and does not seem strong to me. I believe I'm looking at a rich running stove. Here is some photos of the flame running on 4.
Pellet stove.jpg

Pellet stove #2.jpg


Here is what I have done so far:
- Clean out Exhaust pipe, exhaust pipe T and insured no blockages
- Cleaned outside air pipe and insured no blockages
- Cleaned out: Full stove, burn box, all holes in burn box, under burn box, ignitor area, exhaust fan and exhaust fan passage, Cleaned ESP probe, Cleaned out Pellet Metering Slide Plate ( I followed the harman P43 owners manual and have done the full yearly service)
- Inspected Seals on the hopper lid, Glass door and lower door. All look to be O.K. (no signs of a vacuum leak from these seals)
- Replaced the ESP with new OEM Harman sensor
- Ran stove on test mode, Inspected flap on inlet air. It moves freely. Both Fans run O.K. Still re-cleaned both fans and blades once again.
- Changed between 3 brands of pellets
- Ran stove with outside air off and on. No change.

I get no fault codes, But after about 5-6 hours of burning the glass is completely black. The flame is very high on every setting. Am I missing something obvious? Any help would be greatly appreciated.
 

SciGuy

Feeling the Heat
Aug 17, 2007
299
Constableville, NY
Did the problem start all of a sudden after cleaning the fines box that houses the slide plate? It's extremely easy to not get the cover back on correctly, and end up with a lazy flame like you have. I'vet.
done it at least twice in the past when I was certain I had it on correctly.

I'd first triple check that.

Hugh
 
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jackman

Minister of Fire
Jan 15, 2013
623
Oregon
It's hard to tell from a still image but that could be normal. Does it do the same in stove temp/constant burn or room temp mode? If you are running in room temp try moving the temperature sensor to another location. You should turn the feed rate down to 3 and burn for another day or 2.
 
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Washed-Up

Minister of Fire
Nov 5, 2011
664
Kananaskis,Alberta, Canada
Looks a little lazy, follow what Hugh and Jackman have suggested. As for the OAK(fresh air intake) leave that hooked up, it’s good to have. Have you switched pellets? Only other thing I can think of is the combustion motor, if it’s the original 2 fan blade model, make sure it’s clean and oiled at the bearings.
 
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Harman Lover 007

Minister of Fire
Make sure your fines box cover is securely attached and that the igniter cover on the burn pot isn’t installed upside down.
 

mcnajason

New Member
Jan 3, 2021
2
Ottawa, Canada
Thank you for the replies guys. I'm feeling a little silly. I found the issue. The grate located at the end of the exhaust was about 3/4 plugged. When I cleaned the exhaust port I slipped the end off and ran a brush through the exhaust. I did not pay much attention to the wire mesh and re-installed it. It was only on my second exhaust cleaning that a noticed the screen. I figured it was going to be something simple that I simply overlooked or missed. Oh well... Learned a lot about the stove. Much appreciate the help!