Classic Bay 1200 Insert Major Troubleshooting

[mike64b]

Hey all - could use some help here before I stupidly waste any more money.

I've got a quadrafire classic bay 1200 insert paired with a Nest thermostat that has worked great until now. Overnight it was running and stopped heating, I figured it was the usual issue where pellets get a little stuck in the hopper and fail to drop, turns out not. Tried multiple resets, tried moving around pellets around the chute and digging em all out of the hopper but still couldn't get it to drop even though heat was being called for (red light and everything else looked/sounded normal.

Well I started doing more diagnosing and checking snap discs, of course being in a rush I made a horibly stupid mistake and shorted snap disc #1 (purple wires, for the convection blower) while it was live and accidentally touched the metal case. Big shock and now there was zero indication of life on the control box (no lights, no fan noises, no nothing). I pulled the control box out and found a blown relay IC and probably more damage that was not visible on it. I confirmed power was still present at the control box so I definitely had a bad control box now.

I ensured power was off now this time and used a DMM to correctly test all 3 snap discs this time, they all checked out fine and I also confirmed snap disc #3 was not in need of being reset. I then checked the fuse and verified it was still good. It was looking like just the control box was bad - ended up getting a new one and popping it in. Upon power up, we had lights back, and all was looking promising until I turned up the thermostat - this time the call light came on and quickly after a small pop sound was heard in the control box. Again it sounded/smelled like something got fried in the control box.. Lights were still on but no activity on the stove, IIRC no fan and no pellets dropping.

So - obviously, huge waste of money & stupidity aside - my conclusions are that there is obviously a residual problem I need to find and fix before buying YET another controlbox and wasting it. I don't know if it is related to the original problem of pellets failing to feed or if all from the shock breaking more things. In any case - does anyone have suggestions on next steps or guesses as to what might be the problem - if nothing else I was going to start trying to manually test the blower, convection fan, pellet motor, etc individually? Making matters worse is that this stove is hours away from me in a cabin right now and I need to drive up to it with parts, so not sure what I'm going to do, ideally I could pair down to a subset of parts that are the most likely issue and I can buy and take those up with me...

 

[johneh]

Maybe a stupid Question: Do you have a manual?
Did you do the Diganoises as per the manual?
If everything runs (fans) my first impression would be Vac Switch
or something preventing vacuum, eg, a dirty stove .
Your short can not comment . Just test everything, including wiring

 

[Whitenuckler]

Hey all - could use some help here before I stupidly waste any more money.

I've got a quadrafire classic bay 1200 insert paired with a Nest thermostat that has worked great until now. Overnight it was running and stopped heating, I figured it was the usual issue where pellets get a little stuck in the hopper and fail to drop, turns out not. Tried multiple resets, tried moving around pellets around the chute and digging em all out of the hopper but still couldn't get it to drop even though heat was being called for (red light and everything else looked/sounded normal.

Well I started doing more diagnosing and checking snap discs, of course being in a rush I made a horibly stupid mistake and shorted snap disc #1 (purple wires, for the convection blower) while it was live and accidentally touched the metal case. Big shock and now there was zero indication of life on the control box (no lights, no fan noises, no nothing). I pulled the control box out and found a blown relay IC and probably more damage that was not visible on it. I confirmed power was still present at the control box so I definitely had a bad control box now.

I ensured power was off now this time and used a DMM to correctly test all 3 snap discs this time, they all checked out fine and I also confirmed snap disc #3 was not in need of being reset. I then checked the fuse and verified it was still good. It was looking like just the control box was bad - ended up getting a new one and popping it in. Upon power up, we had lights back, and all was looking promising until I turned up the thermostat - this time the call light came on and quickly after a small pop sound was heard in the control box. Again it sounded/smelled like something got fried in the control box.. Lights were still on but no activity on the stove, IIRC no fan and no pellets dropping.

So - obviously, huge waste of money & stupidity aside - my conclusions are that there is obviously a residual problem I need to find and fix before buying YET another controlbox and wasting it. I don't know if it is related to the original problem of pellets failing to feed or if all from the shock breaking more things. In any case - does anyone have suggestions on next steps or guesses as to what might be the problem - if nothing else I was going to start trying to manually test the blower, convection fan, pellet motor, etc individually? Making matters worse is that this stove is hours away from me in a cabin right now and I need to drive up to it with parts, so not sure what I'm going to do, ideally I could pair down to a subset of parts that are the most likely issue and I can buy and take those up with me...

Here is the manual

https://downloads.hearthnhome.com/installmanuals/CLASSIC_BAY_1200_C_PELLET_INSERT_OWNERS_7027_805.PDF

Per Johneh you are going to need to check everything. You may have damaged some insulation on a wire too. No sense in buying parts yet.

 

[AllenQFCB1200]

Just speaking to the short, but whatever wire you grounded would be the first wire I would look at. I mean when a wire is grounded it can get hot and possibly melt the insulation somewhere it it was already weak. Regardless I'd look everywhere that the wiring runs through the housing ect. It's also possible, though a pain to do so, but to test the continuity or each wire and even see if it is grounded do that and find which wire is causing the problem.

But if it were me I'd look real close at the wire you grounded out and where it leads too.

 

[mike64b]

Hi all

I spent all day today testing literally every component - every snap disc, vac switch, igniter, both blowers, auger motor, and thermostat. Also checked all wires for shorts but those all seemed fine.

Turns out I had a couple issues:
1) Vac switch hose was definitely clogged a bit, cleaned it out and resolved that

2) The auger motor / tube was definitely jammed, I manually gave it 120vac power but it would only hum and not turn, even after cleaning out all the pellets fromm the hopper I couldn't get it to turn. Finally disconnected the set screw on the motor shaft and pulled the auger out a bit to clean the tube better - I had a LOT of saw dust stuck in there which I am guessing made a complete jam and prevented it from turning at all.

3) The control board was definitely bad. The microfuse had blew and there was visible damage to the 8pin IC AQH2223 (a solid state relay). Looking at the board I figured out that it goes pin 10 -> microfuse -> AQH2223 relay, and then looking at the wiring diagram we see pin 10 is the switched power for the auger.

Given this, I have a guess as to what happened here:

Initially, when it stoped working at night, it was due to the saw dust build up blocking the auger from turning - I believe this build up caused a large surge in current draw from the motor, enough to kill the AWG2223 chip relay on the control box. (The accidental short I caused when testing the snap discs only further killed the control box to a point where it had no life/leds at all).

When I subsequently tried the second control box, I had not remedied the stuck auger issue, and thus once again as soon as I turned it on it blew the same micro fuse and relay IC (interestingly this occured almost immediately upon calling for heat).

Finally the problem was fixed when I resolved the stuck auger issue and replaced the control box (for a 3rd damn time).


Now - I am very curious if my guess is correct here, because for one, this seems like a terrible design to have the control board be vulnerable to destruction in the case of a stuck auger (which I imagine is a common-ish occurrence). I also am somewhat skeptical of this because the AQH2223 has an RMS load current of 0.9A and 9A peak. The auger motor is 60mA typical - so it would need sustain an over 15x current load increase when in the stuck position. This seems like a lot but googling around is potentially within the realm seen with locked rotor amperage. As I understand it, the capacitor on the motor is intended to allow the motor to reverse direction when under severe load to free up jams, so I suppose in my case, the motor had to have been stuck in both directions and could not move at all.

 

[Whitenuckler]

Hi all

I spent all day today testing literally every component - every snap disc, vac switch, igniter, both blowers, auger motor, and thermostat. Also checked all wires for shorts but those all seemed fine.

Turns out I had a couple issues:
1) Vac switch hose was definitely clogged a bit, cleaned it out and resolved that

2) The auger motor / tube was definitely jammed, I manually gave it 120vac power but it would only hum and not turn, even after cleaning out all the pellets fromm the hopper I couldn't get it to turn. Finally disconnected the set screw on the motor shaft and pulled the auger out a bit to clean the tube better - I had a LOT of saw dust stuck in there which I am guessing made a complete jam and prevented it from turning at all.

3) The control board was definitely bad. The microfuse had blew and there was visible damage to the 8pin IC AQH2223 (a solid state relay). Looking at the board I figured out that it goes pin 10 -> microfuse -> AQH2223 relay, and then looking at the wiring diagram we see pin 10 is the switched power for the auger.

Given this, I have a guess as to what happened here:

Initially, when it stoped working at night, it was due to the saw dust build up blocking the auger from turning - I believe this build up caused a large surge in current draw from the motor, enough to kill the AWG2223 chip relay on the control box. (The accidental short I caused when testing the snap discs only further killed the control box to a point where it had no life/leds at all).

When I subsequently tried the second control box, I had not remedied the stuck auger issue, and thus once again as soon as I turned it on it blew the same micro fuse and relay IC (interestingly this occured almost immediately upon calling for heat).

Finally the problem was fixed when I resolved the stuck auger issue and replaced the control box (for a 3rd damn time).


Now - I am very curious if my guess is correct here, because for one, this seems like a terrible design to have the control board be vulnerable to destruction in the case of a stuck auger (which I imagine is a common-ish occurrence). I also am somewhat skeptical of this because the AQH2223 has an RMS load current of 0.9A and 9A peak. The auger motor is 60mA typical - so it would need sustain an over 15x current load increase when in the stuck position. This seems like a lot but googling around is potentially within the realm seen with locked rotor amperage. As I understand it, the capacitor on the motor is intended to allow the motor to reverse direction when under severe load to free up jams, so I suppose in my case, the motor had to have been stuck in both directions and could not move at all.

Good job troubleshooting - sorry about the control cards. Perhaps you can change the chips if you can. The auger motors are so small you would think they would have to almost catch on fire before they could draw that much current. I added a fuse panel:

Thread 'Harman P43 Fuse Panel'

Oct 5, 2025

I just finished getting things a bit more presentable. I finally broke down on bought a label machine. First time using automotive type wire tape.
I have been running it for quite a long time and the fuse size is good. I already used the switches when I did my cleaning. I had only the AC and Combustion blower switches on in test mode. I only had to add one extra set of disconnects other than what was already there. I didn't want to dig in the back to find them. I did all the work through the circuit card opening. I have some other pictures and if anyone wants more info let me know.

• Whitenuckler
• Replies: 2
• Forum: The Pellet Mill - Pellet and Multifuel Stoves

• 

 

[ARC]

I added a fuse panel:

When OP said he blew another board I thought about your thread. I would be adding a fuse to that line if it blew two boards.

 

[Whitenuckler]

When OP said he blew another board I thought about your thread. I would be adding a fuse to that line if it blew two boards.

Could simplify the trouble shooting for sure. Those auger motors should be fused for sure.

 

[mike64b]

Good job troubleshooting - sorry about the control cards. Perhaps you can change the chips if you can. The auger motors are so small you would think they would have to almost catch on fire before they could draw that much current. I added a fuse panel:

Thread 'Harman P43 Fuse Panel'

Oct 5, 2025

I just finished getting things a bit more presentable. I finally broke down on bought a label machine. First time using automotive type wire tape.
I have been running it for quite a long time and the fuse size is good. I already used the switches when I did my cleaning. I had only the AC and Combustion blower switches on in test mode. I only had to add one extra set of disconnects other than what was already there. I didn't want to dig in the back to find them. I did all the work through the circuit card opening. I have some other pictures and if anyone wants more info let me know.

• Whitenuckler
• Replies: 2
• Forum: The Pellet Mill - Pellet and Multifuel Stoves

• 

great idea on the individual fuses, I will have to set something up like that for my stove (is a shame that's not already built into the design!) And yeah I plan to getting a new solid state relay chip and replacing it on the board so I've got a backup - luckily its only like a $1 for the part.