PC 45 Feeder Issues

[slutzko]

I have a PC 45 Corn stove that recently stopped feeding fuel.
I took the feeder motor off, bench tested and it did not work. Purchased a new one and installed but still not working.
The combustion/exhaust fan turns and all the lights in the control board light. I tested the wires coming to the feeder motor and I am getting power at the white wire, nothing on the black. I also checked the Low pressure switch for power which I am getting on one side (the side that has two wires coming in) nothing on the single wire side. I put the stove into test mode and everything works but the feed motor. I also cleaned the whole unit as well as the T trap outside. Not sure where to go from here or what/how to test further. Any help would be greatly appreciated we certainly can not afford to have a service tech out. Thanks Shawn Lutzko

 

[bags]

Can you trace said wires and see if there is any damage?

 

[slutzko]

Can you trace said wires and see if there is any damage?

The wires appear fine with no damage and everything seems connected. My question is would there be power at both sides of the low pressure switch? I am only getting power on one side.

 

[jzm2cc]

Assuming the exhaust motor is running and you have vacuum inside the burn area, the vacuum switch contacts should close and no voltage should be read across it. Some switches have 3 contacts instead of two or two different vacuum portd so the operation could be reversed with regard to NO or NC with vacuum applied. Suggest taking a picture of vac switch for reference, then try jumping across wires to see if auger now runs when it should. Or if u r handy with a multi meter, with vac switch wires unplugged, measure resistance across vac switch terminals when you put a vacuum to switch. It should go from infinite resistance to near zero.

 

[Lake Girl]

Page 29 of the manual for wiring schematics. I would try jumpering out the vacuum switch to see if that allows the auger to function. The pump that works in conjunction with the igniter could also be failing and it is connected to the vac switch.
http://downloads.hearthnhome.com/installManuals/PC45.pdf

Last time door/ash pan/hopper gaskets (as appropriate) where checked with the dollar bill test?

 

[johneh]

Did you test the new motor ?
I know a dumb question
White wire should have power black wire is a ground
I think you got a bum motor Just a guess

 

[rona]

There is a box that is in back or close to the control board. You have to take some shields off to see it . This box has a wing nut holding the cover. Remove it and clean it out then before you put the cover back on take a careful look at the mechanism that opens and closes the slide on the bottom of the hopper. You can get it wrong and the auger motor won't turn. This happened to me a while ago and I had a tough time before I realized what I did.. Human error was my problem and once I seen how it worked it was clear something went together wrong. Been working fine for several years now.

 

[slutzko]

Assuming the exhaust motor is running and you have vacuum inside the burn area, the vacuum switch contacts should close and no voltage should be read across it. Some switches have 3 contacts instead of two or two different vacuum portd so the operation could be reversed with regard to NO or NC with vacuum applied. Suggest taking a picture of vac switch for reference, then try jumping across wires to see if auger now runs when it should. Or if u r handy with a multi meter, with vac switch wires unplugged, measure resistance across vac switch terminals when you put a vacuum to switch. It should go from infinite resistance to near zero.

I go zero when the stove is turned on - all of the lights work in the board and everything works in test mode except the feed motor.
I am getting power to the white wire going to the feed motor and when testing white to black resistance it is .09 - Could it be possible we got a bad motor?

 

[jzm2cc]

Power motor directly, it will either try to turn or not. Not sure what scale your meter is on, but 0.09 ohms is a short in the windings, but it could be 9 or 90 ohms too.

I still suspect vacuum switch. Does air pump come on when u r trying to start stove? If vac switch is faulty it won't

 

[slutzko]

Power motor directly, it will either try to turn or not. Not sure what scale your meter is on, but 0.09 ohms is a short in the windings, but it could be 9 or 90 ohms too.

I still suspect vacuum switch. Does air pump come on when u r trying to start stove? If vac switch is faulty it won't

The combustion motor comes on I believe that is what you mean by air pump. I am attaching a few photos, one of the low pressure switch, one of the combustion motor and the other of the new feed motor we bought.

 

[Lake Girl]

You tried by-passing the vacuum switch? Cleaned out the fines box and ensured the cover is replaced appropriately?

Edit: Picture of the air pump that rona and I referred to. A re-build kit is the cheaper option.
https://www.stove-parts-unlimited.com/Harman-Ignition-Air-Pump-p/3-20-02679.htm
https://www.stove-parts-unlimited.com/Harman-Air-Pump-Rebuild-Kit-p/1-00-724135.htm

 

[slutzko]

You tried by-passing the vacuum switch? Cleaned out the fines box and ensured the cover is replaced appropriately?

I cleaned out the fines box and made sure the cover is on right. how would i go about by passing that switch?

 

[Lake Girl]

A wire that can be put into each of the spade connectors on the vacuum switch just make sure there is no potential to short against the stove. Some folks get appropriate sized male spade connectors for each end of the wire so it cleanly connects. Remember to unplug while working in the cabinet so you don't short the board.

 

[slutzko]

A wire that can be put into each of the spade connectors on the vacuum switch just make sure there is no potential to short against the stove. Some folks get appropriate sized male spade connectors for each end of the wire so it cleanly connects. Remember to unplug while working in the cabinet so you don't short the board.

The motor worked! Can I run it like this until we get the replacement low pressure switch?

 

[Lake Girl]

May not be the pressure switch itself ... could be air infiltration around door/ash pan/hopper gaskets, could be a leak on the air line attached to vac switch.

Edit: To test gaskets, dollar bill or similar closed in door. If it can be removed easily, time to change out gaskets. Local hardware should have appropriate gaskets. Some members prefer the grey gasket as they are impregnated with graphite and appear to hold up better. Air line must be high temp but should be able to source at local auto parts store.

It is not advisable to run the stove with the vac switch jumped out as the by-pass is only for troubleshooting. If you have a local Harman dealer, they may have the vac switch in stock.

Keep us posted...

 

[salt & battery]

May not be the pressure switch itself ... could be air infiltration around door/ash pan/hopper gaskets, could be a leak on the air line attached to vac switch.

Edit: To test gaskets, dollar bill or similar closed in door. If it can be removed easily, time to change out gaskets. Local hardware should have appropriate gaskets. Some members prefer the grey gasket as they are impregnated with graphite and appear to hold up better. Air line must be high temp but should be able to source at local auto parts store.

It is not advisable to run the stove with the vac switch jumped out as the by-pass is only for troubleshooting. If you have a local Harman dealer, they may have the vac switch in stock.

Keep us posted...

if there is a tiny leak the pressure switch will shut the stove down so it would be working right that is what it is supposed to do. I have jumped mine and run it that way. I think the vacuum pressure switch is to sensitive

 

[MtDew]

Is the clear vac. hose attached to your vac switch. It's hard to tell from the picture but looks like you have an open port on the vac switch.

 

[Lake Girl]

if there is a tiny leak the pressure switch will shut the stove down so it would be working right that is what it is supposed to do. I have jumped mine and run it that way. I think the vacuum pressure switch is to sensitive

As it is part of the OEM for the stove, don't agree that it should be run that way. It is also a risk if there are stove problems as your homeowners insurance will not honor any claims due to modification of the stove

Is the clear vac. hose attached to your vac switch. It's hard to tell from the picture but looks like you have an open port on the vac switch.

There are two ports on the vacuum switch ... there is a hose there in the background. As long as it is the right port .. normally open.

 

[slutzko]

I replaced the low pressure switch, still no feeder motor working. We tried running it for a while bypassing the switch and lots of smoke but would not fire. The combustion motor is running - igniter works - blower motor runs in test mode. I am going to try replacing the gasket but I really cant see that is the problem. Could the combustion motor be the problem?

 

[Tails1]

I replaced the low pressure switch, still no feeder motor working. We tried running it for a while bypassing the switch and lots of smoke but would not fire. The combustion motor is running - igniter works - blower motor runs in test mode. I am going to try replacing the gasket but I really cant see that is the problem. Could the combustion motor be the problem?

If you replaced the switch, either the new one is faulty, it's not connected correctly or you still have a low vacuum issue within the firebox.
I would think that you are having a low vacuum issue due to the difficulty of getting the fire to light. A faulty combustion motor, plugged exhaust (or OAK) or a leaky gasket is what I think you need to look for now.

 

[Lake Girl]

Exhaust venting and internal exhaust passages clean? ESP clean? Fines box cover on securely? New hose on the pressure switch?

Install new door/hopper/ash pan gaskets (as appropriate) as they are likely due. Could be the air pump that is required for igniting as rona and I mentioned above...

 

[rona]

Exhaust venting and internal exhaust passages clean? ESP clean? Fines box cover on securely? New hose on the pressure switch?

Install new door/hopper/ash pan gaskets (as appropriate) as they are likely due. Could be the air pump that is required for igniting as rona and I mentioned above...

I could repeat the idea that you might have mistakenly moved the mechanism that opens and closes the slide on the hopper. With the hopper empty and power off remove that wing nut and door to so you can see the slide open and close. Then you should be able to turn the auger by hand . Maybe loosen the connection between motor and auger then turn the auger watching how the slide opens and closes as the auger turns. It is easy to get this part on wrong when replacing the auger motor.