Harman Accentra issue with pressure switch/air flow

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New Member
Mar 15, 2021
Lemon Grove, CA
My Harman Accentra pellet stove stopped working a few weeks ago. Using the manual and doing some diagnostics I discovered a possible issue with the control board, which I replaced. I set the dip setting the same as old board and settings seemed to agree with sheet that came with new board. Now I get the status light which blinks twice. That trouble code was not in in the manual (had the rest of trouble codes in manual), but found online which indicates an air flow/pressure switch issue. To be on the safe side I went ahead and replaced the switch. Since then I have tried activating the switch manually (sucking/blowing on tubing to switch) and even bypassed switch. I still get trouble code on the status light of two blinks. I'm kinda at a loss of where to process from here.
2 Blinks: Indicates an open feed circuit, typically from pressure switch or hopper switch.
Blink status automatically clears when feed circuit is complete.
Does not blink if door/ hopper is opened when stove is off.

How's the hopper switch & hopper door gasket?

Not sure what year your stove was manufactured, so I can't tell you for sure.
My P61A has it on the corner of the hopper where the closed door actuates it.
Compare the wiring diagram I posted with the one on your stove.
I don't know exactly where yours might be. My P61A has it on the inside of the rear shroud.
Your diagram is the same as mine except for the Room Sensor wires. There is no door switch, only the Low Pressure Switch. I have tried to bypass the Low Pressure Switch as well with no success. The low pressure switch is the only thing between the control board and the feed motor. Also the Low Pressure Switch controls the Ignitor Element.
At least now with your assistance, I know I need to test for power between the white (low pressure switch) and black lead (feeder motor) to see if I have power there. Only thing I can think of is a bad wire in the circuit, which may be the issue.