Pellet stove won't cool down

[jonnykegz]

So I have a Harman Accentra pellet stove insert (ACC52i) and my problem is, after I turn it off, the flame goes down and everything and it cools down for the most part, but the combustion blower won't stop running! It will run for hours, days even, until I turn off the circuit breaker and then turn it back on. Then it will stop. After I turn off the stove, hours later, the burn pot will still be warm , almost like the igniter is on slightly, but enough to keep the combustion blower running.

So this is the 4th year I've had it and it has worked flawlessly up until this year. I started getting it ready for the cold season this year, and now I have issues. So here is what I've done to it this year so far. So I tried running it for the first time and nothing, no LED's or anything. Checked the 6 amp fuse in the board and it was completely blown with black soot around it and everything. I replaced the fuse and got it to start trying to start up, but the burn pot wouldn't heat up. Checked the igniter and igniter was bad. I replaced the igniter and it came on with normal flame and blowing and everything, but then when I would turn it off, that's when I noticed the combustion blower would just keep on running and running and running. I pulled the stove apart, re-vacuumed everything, cleaned out the exhaust and even blew out the flu going up the chimney. I pulled out the ESP sensor and cleaned it off real good and put it back in. The sensor looked brand new after I cleaned it and wasn't that dirty to begin with. Put everything back together, and still, combustion blower won't shut off!

I was thinking about replacing the ESP next, but just have a bad feeling my board is damaged. And no, I did not have it on surge protection, but that will change soon. Any suggestions?

Thanks!

 

[DAKSY]

Replace the ESP. It's the cheaper part & if it's not the issue, you will have a spare.

 

[Overfireinthehole]

A vacuum switch not closing will run the combustion blower forever but if it burns correctly it’s possible esp is not reaching low enough temps. I will say as those Acentras get older they take longer to cool down. The newer board kicks the room blower on sooner and runs it longer and I believe it shuts the combustion blower off quicker, but I’m going off memory and not looking at the temp table.

 

[rickwai]

Try ESP first then if problem persist, replace board. I replace the ESP when I do a board regardless. That way you have all new controls.

 

[jonnykegz]

I replaced the ESP and problem persists. I guess I will try replacing the board next, but I am concerned. It's a $250 dollar part and this is only the 4th year we've had it. I will say I did not have it on surge protection, and the next board I will. Was it most likely a surge that took out the fuse and the board?

Thanks

 

[Montecarlossfan]

I replaced the ESP and problem persists. I guess I will try replacing the board next, but I am concerned. It's a $250 dollar part and this is only the 4th year we've had it. I will say I did not have it on surge protection, and the next board I will. Was it most likely a surge that took out the fuse and the board?

Thanks

Based on your findings of a bad igniter, that is what killed the fuse and probably took the board with it. I installed a (4A)fuse inline with my igniter when I replaced it just to prevent this.

 

[rich2500]

I agree with Monte and did the same thing with the inline fuse.

 

[jonnykegz]

Just wanted to follow up on this, after replacing the ESP, problem persisted so I replaced the board and problem solved!

I may try the inline fuse for the igniter, do you just pick any one of the two wires to the igniter to put the fuse in line with?

Thanks

 

[rich2500]

Put it in the yellow wire

 

[jonnykegz]

Ok, thanks!