Harman XXV auger not turning in test mode

[87fethers]

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?

 

[Washed-Up]

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

 

[87fethers]

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.

 

[gfreek]

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:

Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP

A pressure switch is often referred to as a vacuum switch. This sensor is looking for airflow within the stove to close the circuit to the feed system and the igniter. If your stove is feeding pellets, your pressure switch is ok. Replaces part numbers 3-20-9301 & 3-20-3433. Check out our huge...

pellet-stove-parts-4less.com

 

[87fethers]

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:

Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP

A pressure switch is often referred to as a vacuum switch. This sensor is looking for airflow within the stove to close the circuit to the feed system and the igniter. If your stove is feeding pellets, your pressure switch is ok. Replaces part numbers 3-20-9301 & 3-20-3433. Check out our huge...

pellet-stove-parts-4less.com

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.

 

[gfreek]

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...

Harman Hopper Lid Switch (48"): 3-20-232108

The function of the hopper lid switch is to cut the power to the feed system if the hopper lid is opened at any time during operation. ASTM safety requirement of installing a lid switch was introduced to pellet stoves made in 2008. XXV, P43, PC45, P61A, P68, Accentra- Cast, Accentra Insert...

pellet-stove-parts-4less.com

 

[87fethers]

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:

Harman Differential Pressure Sensor Vacuum Switch: 3-20-6866-AMP

A pressure switch is often referred to as a vacuum switch. This sensor is looking for airflow within the stove to close the circuit to the feed system and the igniter. If your stove is feeding pellets, your pressure switch is ok. Replaces part numbers 3-20-9301 & 3-20-3433. Check out our huge...

pellet-stove-parts-4less.com

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?

 

[johneh]

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

 

[gfreek]

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 ??

 

[87fethers]

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?

 

[87fethers]

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

 

[gfreek]

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.

Harman Muffler and Fitting for Hopper Mounted Pressure Switches: 1-00-18186618

This is the air pressure monitoring fitting which is mounted inside of the hopper on many Harman pellet stoves, inserts, and furnaces manufactured at various periods prior to 2008. All Harman products made after 2009 do not use this fitting. When the glue on this fitting fails, the pressure...

pellet-stove-parts-4less.com

Harman Hopper Lid Switch (48"): 3-20-232108

The function of the hopper lid switch is to cut the power to the feed system if the hopper lid is opened at any time during operation. ASTM safety requirement of installing a lid switch was introduced to pellet stoves made in 2008. XXV, P43, PC45, P61A, P68, Accentra- Cast, Accentra Insert...

pellet-stove-parts-4less.com

 

[87fethers]

The latest update:

I swapped out the exhaust motor for a new one, and so far so good. I'm testing out "automatic mode" now and it seems to be working. I'll monitor a bit and see how it goes.

Thank you everyone!

 

[carnini]

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.