Harman XXV auger not turning in test mode

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87fethers

New Member
Apr 17, 2022
10
New Hampshire
Hi All,

I bought a 2 familly house with a Harman XXV pellet stove that was installed in 2008. I'm new to pellet stoves, and this one doesn't want to start. I noticed the auger wasn't turning, so I thought it might be jammed. I emptied the hopper, and using YouTube videos as a guide, I slide out the auger halfway out to try to clear any jams. I reassembled and it still will not turn in test mode. Also, the light doesn't turn on. Any thoughts on what my next steps to triage and fix should be? harman_XXV.jpg
 
Make sure the door the fire box door is closing properly, you might have to open and close it a few times while it’s in test mode, try the hopper lid the same way separately
 
Make sure the door the fire box door is closing properly, you might have to open and close it a few times while it’s in test mode, try the hopper lid the same way separately
Thank you for replying. After you posted, all the latches look to be sealing tightly, and I tried opening and closing multiple times.
 
I see in the picture that the lights are on for the combustion and distribution blower, do they actually work ? If so, I would unplug the stove, there is a pressure switch with a hose and two wires connected to it.., remove the two wires and connect them together, thus bypassing the pressure switch.. and try the test mode again.. looking from the rear it would be to the right of the auger motor.. This is for testing Only..& not to run the stove..Report back.. similar to this switch:
1650307637938.png
 
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I see in the picture that the lights are on for the combustion and distribution blower, do they actually work ? If so, I would unplug the stove, there is a pressure switch with a hose and two wires connected to it.., remove the two wires and connect them together, thus bypassing the pressure switch.. and try the test mode again.. looking from the rear it would be to the right of the auger motor.. This is for testing Only..& not to run the stove..Report back.. similar to this switch:
I saw the pressure switch when I was working on it on Sunday. I was curious what it does, and I was able to trace it back to a yellow connector where you dump the pellets in. It seems like an odd place to have hooked up to, and I am curious about the design.

I will try bypassing it tonight and see if I get the auger to move in test mode.
 
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OK, so it was installed in 08, that stove version would likely have a hopper lid switch, which stops feeding pellets when the lid is open, which also could be a cause...
 
I see in the picture that the lights are on for the combustion and distribution blower, do they actually work ? If so, I would unplug the stove, there is a pressure switch with a hose and two wires connected to it.., remove the two wires and connect them together, thus bypassing the pressure switch.. and try the test mode again.. looking from the rear it would be to the right of the auger motor.. This is for testing Only..& not to run the stove..Report back.. similar to this switch:

I made a jumper for the the pressure switch to test. The auger turns and light for the feed motor turns on. Does this mean the pressure switch is bad, or there is an obstruction I need to look for?
 
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Pull the hose off the back of the sensor and blow through it towards the firebox
air should move through it. If it does most likely the sensor is not working and
needs replacement. There could be other causes door gasket major leak pellet
lid, combustion fan not working
 
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I made a jumper for the the pressure switch to test. The auger turns and light for the feed motor turns on. Does this mean the pressure switch is bad, or there is an obstruction I need to look for?
The pressure switch senses pressure in the stove...check the hose from the pressure switch to the stove for cracks or breaks, check hose for blockage blow thru it and where it's connected to the stove for blockage, bad door or ash door gasket do a "dollar bill test" search "pellet stove dollar bill test", fines door not installed properly, bad gasket for combustion blower..Do you have the owners manual ??
 
An update. I removed the pressure switch and tested it with a multi meter. It's working correctly, under vacuum the the circuit completes. I tested all the seals with the dollar bill test and they seem fine. Don't see any issues with the vacuum line.

I don't understand why the pressure switch is connected to the hopper though. Is there supposed to be a vacuum in the hopper?
 
Another update. I disconnected the stove by removing the 3 3/8th size bolts and turned the stove. When I run it in test mode, the fan blades are not turning. I think this is the exhaust blower
 
Another update. I disconnected the stove by removing the 3 3/8th size bolts and turned the stove. When I run it in test mode, the fan blades are not turning. I think this is the exhaust blower
So the exhaust fan is needed to create vacuum, should come on immediately at start or test mode..if not working there is no vacuum for the pressure switch. Depending on the age of your stove, it will either have a hopper switch which is wired in line (series) with the auger motor ( lid open auger will not turn) or a "muffler" hopper mounted pressure fitting connected via hose to the vacuum switch.
 
Similar issue on my stove not feeding or starting. Had it cleaned today and suddenly it would not start up again. The exhaust motor would start but not the ignitor or the feed motor. On test mode the exhaust and distribution motor would start but not the ignitor or the feed motor.

I checked the back of the stove ( I have one of the exahust that make it look like a wood stove pipe), and due to cleaning a lot of ash had got down into the lower pipe. I cleaned the part out and still would not start (not it was working the day before).

I checked the pressure switch and the tube looked good and there was nothing I could see leak wise.

I ended up disconnecting the pressure switch and placing a wire between the two to check if that was the issue. Once I bypassed the pressure switch the stove started right up. My assumption is bad timing and the pressure switch just died.

Ordered a new one and well see if that fixes it when replaced.