Harman Accentra Insert - Room blower does not stop after stove cools down?

[Don2222]

Hello

This is a wierd problem because unlike most stoves there is no low limit snap disc controlling this function. The stove is approx 4 years old and works well otherwise. It is on a power strip but does not look like a surge protector. So is it a bad control board? What else can it be?

Couple of pages from the manual attached below. Click to enlarge.
(broken link removed to http://hearthnhome.com/downloads/installManuals/Accentra_Insert.pdf)

 

[Murph]

Does the blower start normally when the stove temp is high enough to trigger it? Is it only the shutting down that is the problem.

 

[Don2222]

Does the blower start normally when the stove temp is high enough to trigger it? Is it only the shutting down that is the problem.

The only way to shut it down is to unplug the unit. So yes I believe it starts normally when the unit is plugged back in.

 

[Bioburner]

Could be just a bad pot switch that seems to be common problem with our Harman stoves. There is someone that will check and replace for reasonable fee. I do not know where someone posted it,but is on eBay.

 

[Don2222]

Could be just a bad pot switch that seems to be common problem with our Harman stoves. There is someone that will check and replace for reasonable fee. I do not know where someone posted it,but is on eBay.

Pot Switch? Where is it and what does it look like?

 

[papa bears stove]

Don check the esp switch located on the exhaust, its held on by a single self taping screw. Its possible that its dirty. Also touch the potentiometer as sometimes they lose contact.

 

[rickwai]

Bad esp would be most likely. After stove has shutdown and should be cool about 1- 1 1/2 hr open door and check for heat in burn pot. I did have one that the ignitor circuit on the board stuck on and was keeeping ignitor on and not letting stove to cool enough to let fan turn off

 

[Bioburner]

I am sorry, the pot switch is the room temp-stove temp varible switch. They do get alot of work on the harman stoves. Mine currently if I set all the way to high room temp makes the stove do all kind of strange things. Will solder in new one in spring but for now I just do not crank all the way to the stop.

 

[Lousyweather]

throw a DDM on the cold stove and see what the ESP is reading.....if reading correctly (I dunno....70 degrees, etc?), its the board. Look for a reading of 572 degrees F on a cold stove (the magic "bad" ESP number)...spretty much ensures its a bad probe, as long as your dipswitch settings are correct.

 

[kinsmanstoves]

To work on a Harman having a DDM and draft meter are the best tools. Problem is only dealers can get a DDM. Look at the ESP (not a switch), dirty, damaged, or broke. That probe has to register 90 degree to shut off the blower. The last thing could be a board but unlikely.

Eric

 

[wil lanfear]

Pot Switch? Where is it and what does it look like?

https://www.hearth.com/talk/threads/harman-pellet-stove-control-board-repair.95092/

(broken link removed to http://www.ebay.com/itm/Harman-Pellet-Coal-Stove-Control-Potentiometer-50K-P38-/190655476430?_trksid=p2047675.m1985&_trkparms=aid%3D444000%26algo%3DSOI.CURRENT%26ao%3D1%26asc%3D13%26meid%3D4428152563161358409%26pid%3D100012%26prg%3D1014%26rk%3D1%26sd%3D190733182305%26)

 

[Bioburner]

Thanks wil

 

[Murph]

Another possibility is the ESP probe but to test this properly would require a diagnostic reading from a DDM. The ESP tells the stove to start the distribution fan at a certain temperature and to turn it off when it drops below a lower temp. If you clean the stove your self do you clean the probe off through the trap door on the comb housing?

 

[kinsmanstoves]

Another possibility is the ESP probe but to test this properly would require a diagnostic reading from a DDM. The ESP tells the stove to start the distribution fan at a certain temperature and to turn it off when it drops below a lower temp. If you clean the stove your self do you clean the probe off through the trap door on the comb housing?

The ESP does a lot more than work the distribution blower. The ESP wells the computer everything including igniter, combustion blower, distribution blower, and auger.

Eric