Harman PC45 won’t shut off!!!!

[Riderout55]

Hello all! I’m new to this so please bare with me!

I just recently bought a used Harmon pc45! Not the best condition but it does run! The only problem I’m having is it won’t shutoff! Even when In the off position and stove has not been running. As soon as you plug in the blowers start! Exhaust and main blower. I have replaced the esp probe! Cleaned the stove out. I’m kinda at a lost.. FYI I do have new pots ordered in case that could be the issue! I’m just not sure where else to go. Our harman dealer in town is not much help since I didn’t buy a stove from him. Thanks in advance! I’d just hate to always unplug the stove a few hrs after shutting down

 

[Mt Bob]

The pots will probably fix your problem,a very common problem with older Harmans.However,Check the part number on your control board,generally the newer the board,the better the stove reacts and burns.You may want to upgrade your board,and keep your repaired board for a backup.

 

[Riderout55]

Wow thanks so much for the quick reply! I have already ordered the new pots, I’m going to give that a shot first! Hopefully that does fix it! If not I’ll buy a new board and do as you say, I found a new board for around $250. I didn’t think that was to bad. Could you think of any other part that may be bad allowing it continue to run? I’m trying narrow it down

 

[Mt Bob]

Wow thanks so much for the quick reply! I have already ordered the new pots, I’m going to give that a shot first! Hopefully that does fix it! If not I’ll buy a new board and do as you say, I found a new board for around $250. I didn’t think that was to bad. Could you think of any other part that may be bad allowing it continue to run? I’m trying narrow it down

The only part that could possibly create your problems is the exhaust sensor probe.

 

[rickwai]

Pc45 is finicky. The newer boards come with sheet to set it for pellets only . If you are burning pellets only it takes it out of ignition quicker and shut down time is quicker. Acts similar to a P61 ect. They also used to make a conversion kit to convert it to a P61 I think? burn pot igniter, circuit board ect?