HARMAN NOT SENSING TEMPERATURE

[mpoland33]

I have a Harman ACC52i pellet stove with dial controls on the side for control the temp. The dial is no longer working. It moves and all but does not turn on or off the stove. The manual 'on' dial works fine so I'm assuming its a thermostat or sensor. CAn't find a single thing online about it...any ideas??? I like to do things on my own when I can

 

[Washed-Up]

Unplug it….Contact cleaner, pull the knob off, spray it and turn it back and forth, also has the ESP been cleaned recently

 

[Tonyray]

Take the knob off and see if u can turn the knob shaft with needle nose plyers or similar. If it works then knob inards are rounded out.

 

[mpoland33]

Take the knob off and see if u can turn the knob shaft with needle nose plyers or similar. If it works then knob inards are rounded out.

So the knob does turn I believe. off is to the left. If I turn up, it controls it by temperature (which is what isn't activating). If I turn it down, its the manual on which works fine

 

[mpoland33]

Unplug it….Contact cleaner, pull the knob off, spray it and turn it back and forth, also has the ESP been cleaned recently

Where is the ESP typically located? I saw a video that showed one ( i think) on the back inside maybe the fan cylinder?...but to answer your question the companies we deal with say they clean the stove (done in August this year) but I don't recall them doing anything on the back side of it, i.e. clean the ESP

 

[Washed-Up]

It’s inside the stub(tail pipe) at the back of the stove where the exhaust pipe attaches, it can also be accessed by removing the exhaust fan (which can be difficult and ruin the fan if it doesn’t come off easily).

 

[mpoland33]

Million dollar question. I have a roller but its one my in laws gave me- of course it doesnt fit. Any ideas on how to not scratch my hearth area?

 

[Washed-Up]

Can you put some thin plywood or Masonite down n front of it?

 

[mpoland33]

THanks for the help. so I was able to pull it out some but this thing is not easily rollable. I have to yank left to right just for a centimeter. I did pull it out some and saw this....any way to see what kind of wire this is? Just hanging out in there. I'm thinking I'll call someone in at this point. Im hoping/thinking it just needs the ESP cleaned. Now that I know where it is, I guarantee none of the cleaners have touched this in years past.

 

[Washed-Up]

That’s the room temperature sensor…not sure it’s in the beat spot….was it underneath?

 

[bogieb]

The room temp sensor wire as @Washed-Up said. I don't think it should be back there, but I don't have an insert so not the best person to talk about placement.

 

[rickwai]

extend that wire out onto your hearth. It is about 4 ft long. That is what is sensing the room temp. If it is back in the cool fire place the stove will run forever.

 

[gfreek]

I would just replace the ESP as long it is out, clean the old one as a backup..or clean it and keep a replacement on hand....

 

[rickwai]

The room sensing probe hooks up on the left side of stove and typically the wire comes out from behind the left side surround. route it back over to the left side and get the pinched end away from the stove so it can sense the room temp and adjust accordingly.

 

[Tonyray]

Ours is taped to back of hopper but just read u have an insert.

 

[chadhumm]

I have 2 harmans they are both junk . constant repairs . weekly. I have 3 other brands of stoves and work on stoves. The harmans are the only ones that are problematic and when they are running far less effeceint than the other stoves. double the exhaust temp so double the heat lost out the exhaust. 3 esp probes a season on average. Currently both dont work on auto. it like the switch for auto /manual doesnt work so they keep running and overheat the room. The last board did the same thing the new board worked as normal but for only 2 weeks and now I have the same problem again,. maybe something with my electrical service is damaging boards but I dont have issues with anything else or other corn stoves/ I had to modify the pot with a grinder because it didnt fit from the factory. alwys repalcing esp probes. always needs cleaned the stirrer rod forces ash in the pot holes. I prefer top feed and no stirrer. never an issue. These harmans are very poorly designed and not effecient stoves. 30 percent more fuel usage than my st croix, bixby, comfortbilt and my ldj furnace. anyone have an idea why it wont shut off and on when the temp is met. It a garage heater. set on 65 but its 90 out there now. running on minumum feed but wont cycle as it should . its on room temp. the other stove does the same thing. all new parts and esp probes.

 

[Tonyray]

geez,,, don;t have anything to offer.. my harman P61A has been running 24/7 most winters for 9 yrs. couple ignitors and
replaced the blower motor as it was gettin noisy. other than that it's been running problem free for years..

 

[bogieb]

I would check where your room sensor probe is. It sounds like it is too near the floor, wall, or in a draft that tells it is cold. If the placement is correct, check that it is tightly plugged into the socket in back. My P61a had exhibited those symptoms (never shutting fully down - acting like it was on manual instead of auto), and it turns out I (or a cat) had somehow dislodged it slightly from the back connector. It looked fine, but when I touched it, I could feel just a bit of wiggle. Once I got it seated properly, the stove acted as it should.

I've never replaced an ESP on either stove (KOW). Heck, I've never even taken one out to clean them - although I do brush them off a couple of times during burning season when cleaning the exhaust during a good cleaning . I've only replaced an exhaust motor for the P43, but I haven't had to do anything with the P61a (besides some door gaskets). I replaced a St Croix with a used P43 - not because the Hastings was "bad" but because it did not work well for me in my circumstances (and the P61a had spoiled me as far as ease of cleaning/maintenance and not messing with the draft when changing pellet types).