Harman Accentra Insert - Auger won't feed

Hi, new to the forum and impressed by all the advice I see here!

I have an 8yo Accentra insert. It worked fine until this year, and I clean it annually (use about 1ton/year). Now the auger won't turn when I try to start it up, but all the motors (including the auger) work fine when I go into test mode. I tried bypassing the pressure sensor, with no luck. I read that another cause of this would be the hopper lid switch, but for the life of me I can't find such a device on the stove.

Any suggestions for how to debug this?

If the auger works during test mode,... good chance there a sensor needing replacement,...sit tight and one the more experienced Accentra owners will chime in.

You say when you're trying to start it. Seeing you're a veteran with this stove, have you tried lighting the pellets and tricking the stove into feeding by putting it back in test mode after they get going a bit? Could just be an ESP issue (dirty, not hot enough).

High Heat Sensor Tripped?

That will disengage the auger from operating.
The switch is a N.C. style (allowing transfer of power ) If overheated it opens up the contacts not allowing power to flow.
It can be check w/continuity meter or the following:

Just reset it that should fix it.

Or bypass (safely)it if your not sure it`s defective. Result? (if bypassing works ) >
Then buy a new one
Good luck.

any chance someone accidentally flipped the auto/manual switch to manual?

I'm fairly certain that Harmans do not have high heat sensor switches that can be reset.

Thanks for the suggestions - I poked around again with bypassing the sensor and the auger started moving, so i plugged it back together and fiddled with the wires and it's working now. Not sure if the sensor is actually dirty/bad or just had a connection problem, but at least I know what to attack if it's not really fixed.

nice!,... you have it narrowed down.

Cool

I would check to see if your door and ash pan seals are tight. I had the same issue a few years ago and it was because my ash pan door wasn't shutting tight. The boiler's vacuum switch was doing its job. Once I fixed the seal the stove worked perfectly.

If your Harman ever starts to produce creosote it is most likely due to an air leak.

Are you sure the flue, combustion fan chamber and tubes in the bottom that meet in the back right corner are clean. If you are getting anything other than light grey or light tan colored ash or build up in stove you have a blockage. If this stove is run on restricted exhaust it will creosote and gum up and it is a bear to clean out. also if you see a color difference on your cast iron panels inside, left black and right more grey or tan you are getting clogged in the rear tube. In 6 yrs of stove service I have only had to replace 1 vac switch. 99% of the time switch was doing its job and shutting auger down do to improper air flow.

Thanks Andrew and Rick - I'll check those things tonight.