Harman P61A Problem

[richg]

Gang,

An issue has come up that has me a bit frustrated. Another poster had a similar problem, but that thread did not lead to a solution. Setup:

-P61A
-Vented with 4ft rise of straight 3-inch pellet pipe, 45 elbow, 2 ft straight 3 inch piece, and then an adapter takes it to stainless 4 inch flex liner up another 12 feet
-Outside air kit
-Stove is kept cleaner than Felix Unger would. I actually do a Harman "once a year" cleaning once a month.

Problem is that 75% of the time, the flame flickers/flutters heavily, and the stove resonates like a washing machine that is out of balance. Problem is completely aleviated by opening the hopper lid, as the resonating stops and the flame goes from lazy yellow flickering to blue/purple blowtorch. I took the thing completley apart yesterday, including removing the outside air kit, removing the air intake port and sweeping the intake, cleaning the ESP probe, sweeping the vent system, removing fines from the collection site, cleaning the vaccum hose with a pipe cleaner, cleaning out under the burn pot, cleaning motor fins, etc etc etc. No obstructions in the outside air line or internal air intake path were found. Dang thing just seems like it's choking, and my dealer (who is completely clueless) does not know why. He said he called Harman, and they said my issue was completely normal. Not trusting this, I called another dealer who talked to Harman, and the Harman tech said there is definately something wrong with the stove, probably an obstruction in the air intake line. I adjusted the draft screw, nothing, checked to make sure the burn pot air holes were clean, and nothing is found. I know this stove operates on a negative pressure to prevent a hopper fire, but this seems way out of balance. Any ideas would be greatly appreciated, thanks.

 

[richg]

Forgot to mention, I check all gaskets with a dollar bill, and also have video clips of the stove with the hopper closed and the hopper open. Can email the clips if you want, thanks.

 

[Chuck Pearson]

My fire was choking because the louvers that let in the outside air were closed. Are the louvers on the outside of your house open?

 

[GeorgeD]

When my Harman Accentra was installed, I found that it would burn much better with the hopper door open. Another symptom was that the glass would get covered with soot in a few days. Eventually, my dealer found that a flapper valve in the air-in line was not opening all the way. After clearing a silicone sealant obstruction, the flapper was able to open fully. This pretty much cleared the problem.

 

[HarryBack]

When my Harman Accentra was installed, I found that it would burn much better with the hopper door open. Another symptom was that the glass would get covered with soot in a few days. Eventually, my dealer found that a flapper valve in the air-in line was not opening all the way. After clearing a silicone sealant obstruction, the flapper was able to open fully. This pretty much cleared the problem.

Hmmmmmm......NEVER, NEVER burn the stove with the hopper door left open! It introduces an air source to the auger/fuel area, possibly allowing burnback into the hopper....DO NOT DO THIS.
Heres an idea, just to try.......crazy as it sounds, try pulling the outside air pipe away from the intake damper....yep....just pull it back, so its no longer connected, and sitting back away from the intake maybe 2" or so. Did that make a difference? If so, the stove seems to be having trouble getting enough air for combustion. Another thing to check, and this is gonna sound cryptic, buuut....let the hopper get REALLY low, to where theres almost no pellets.....look in the hopper, to the rectangular area where you can see the slide plate.....around this rectangular indent, do you see and yellow/brown/black discoloration? Is there any tarry residue on the auger OR the slide plate (a little hard carbon is normal)?If so, let your dealer know. This would be the first p61a ive seen this with, but I guess its possible.

 

[GeorgeD]

Harry,

I should have been more clear but I only open my hopper door for filling or maintenance.