Harman P43 Distribution Motor High Only

NurseBill

New Member
Feb 2, 2019
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Had a distribution motor seize up. Took the fuse out as well. I bought a replacement blower from a Harman dealer but it only seems to run on high only. Any suggestions?
 

bogieb

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Oct 31, 2014
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Maybe it is an aftermarket blower that does not run at two different speeds?

If it is an OEM replacement then I would be talking to the dealer and see if you can return it.
 

bob bare

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Oct 31, 2013
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Harman convection and combustion blower motors speeds are variable,and speeds are changed by changing the voltage.The exhaust probe is the key to the convection blower,if your fan setting is on high,the blower will ramp up in stages to max.Sounds like the voltage spike from your problem took out the triac,on the control board.
 

NurseBill

New Member
Feb 2, 2019
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Pennsylvania
Harman convection and combustion blower motors speeds are variable,and speeds are changed by changing the voltage.The exhaust probe is the key to the convection blower,if your fan setting is on high,the blower will ramp up in stages to max.Sounds like the voltage spike from your problem took out the triac,on the control board.
Yeah, that's kind of what I was thinking happened. It still works just the fan is on high constantly. Thanks!
 
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greg13

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I was thinking a bad potentiometer on the control board, Try it in both stove & room temp, mode. Mine went out last week have to run in stove mode until new pots get here.
 
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NurseBill

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Feb 2, 2019
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I was thinking a bad potentiometer on the control board, Try it in both stove & room temp, mode. Mine went out last week have to run in stove mode until new pots get here.
Yep same in stove and room temp. It works and does what it is supposed to do just the distribution fan is on high constant. No off either.

I bought this stove when the P43's first came out. The distribution blower went out within a week of delivery and they replaced it. Other than 1 combustion blower.... that's it. I have no idea what year I bought it but I'm thinking 09.
 

gfreek

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You could probably install a rotary ceiling fan speed controller to vary the blower speed..depending on amp rating.. I did that on my Harman coal stove that had a one speed blower..
 
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NurseBill

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Feb 2, 2019
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Pennsylvania
I ended up buying a new board. It had some other issues with it not turning off as well. It's all good now. I asked if they had a record of when I bought the thing September 2008.
 
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bob bare

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I ended up buying a new board. It had some other issues with it not turning off as well. It's all good now. I asked if they had a record of when I bought the thing September 2008.
There is a 99% chance you could cheaply repair your old board,and keep for emergencies.However,I think you will find the new board has better programming,and your stove will run better and cleaner.
 
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NurseBill

New Member
Feb 2, 2019
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There is a 99% chance you could cheaply repair your old board,and keep for emergencies.However,I think you will find the new board has better programming,and your stove will run better and cleaner.
It does seem to run better than it did before. I think the board was going bad either way being it wouldn't turn off unless you left the hopper door open.