Convection blower slow to come on and off - Quadrafire Classic Bay 1200 FS

[Burrn]

My stove (year 2000) calls for heat, ignites, drops pellets, and then lags to turn convection blower on (15+ minutes). Once it reaches temp, the convection blower lags to shut off... 30+ minutes after exhaust blower does. It's super noisy on startup too- grinding metallic noise, but that fades off after the fins spin for a while.. when it is blowing air, it pumps it out like crazy.

Could my control box be getting delayed temperature read from thermocouple somehow? The feed motor seems to come on timely.
The problem is my convection blower is late for the party, super loud at times, and then stays partying too long after the fire goes out
This was not an issue last season prior to a thorough cleaning and maintenance

Here is my thought pattern. Looking for some help from a seasoned quad vet:

Thermocouple- tested with voltmeter and is OK I believe, the end is a little frayed, but snap discs are opening and closing, which means control box is getting a read on temps correct??
Thermocouple cover- new- just replaced
Snap discs 1 and 2- these can't be the issue right? Feed motor and fans coming on and off...
Firepot gasket- new- just replaced
Ash pan- gasket seems OK, securely latched
Door Gasket - not perfect (rope is frayed in spots) but passes the dollar bill test

Heat exchanger tubes all thoroughly cleaned recently, exhaust path is clear and the stove purrs with vacuum, so I don't think any air flow issues. Any ideas?

 

[StockHR]

I had the same problem when my stove was new. It would startup, drop pellets and burn for about 15 minutes before the convection fan would come on and blow heat. I would get plenty of heat but than once the thermostat told the stove to shut off, the convection blower would run for upwards of 45 minutes before it would shut off. Actually cool sir was being blown in prior to it shutting off. my Snap discs 1 was a 110 - 20 meaning turn on at 110 degrees and off at 90 degrees. Not even close. The firebox was close to 150/160 before it turned on and about 70 degrees before I would hear the snap and it would turn off. I put in a new Snap discs 1 and it has worked as expected ever since. I'm now thinking of changing it to a 110 - 10 to have it shut down sooner yet. Anyway most snap discs are cheap, and might be an easy fix just to put in a new one.

 

[Burrn]

I guess I figured if the snap disc would open and close, then the issue would have to be something else telling it what temperature it was. In other words I thought a snap disc either works or doesn't work, but can't work poorly.

Which is why I was thinking maybe it could be something to do with my thermocouple or control box..

I saw on another thread a few people using this snap disc from Grainger:

Snap Disc Control, Adjustable Fan, Switch Closes @ (F) 90 to 130, Switch Opens @ (F) 70 to 110

Adjustable Fan Switch, 90-130

www.grainger.com

You can adjust the temps to what your preference is... I might give that one a try and see if it makes a difference

 

[StockHR]

Looks like a good switch. Can't hurt to try it. Let me know how it works out.

 

[Overfireinthehole]

The thermocouple has no effect on the convection blower. If the motor is noisy you might pull it and blow it out with an air compressor and oil the bearings with 3 in 1. If it’s really noisy, you might replace it. Snap switches can take longer to open and close with age, but you might double check that snap 1 is touching the side of the stove but not tight. If your convinced that there is something else going on, watch your snap and listen for it to close and open and see if the motor is kicking on with the switches changes. The snap switch is literally just completing the circuit that the room blower is on.

 

[Burrn]

The thermocouple has no effect on the convection blower. If the motor is noisy you might pull it and blow it out with an air compressor and oil the bearings with 3 in 1. If it’s really noisy, you might replace it. Snap switches can take longer to open and close with age, but you might double check that snap 1 is touching the side of the stove but not tight. If your convinced that there is something else going on, watch your snap and listen for it to close and open and see if the motor is kicking on with the switches changes. The snap switch is literally just completing the circuit that the room blower is on.

Thanks for the help. I replaced the snap disk and between that and the blades on convection blower being installed a little crooked after deep cleaning I found my issue. Now another problem with the initial feed on startup- thermostat calls for heat and the auger just keeps dumping pellets until its full. I reduced feed rate to almost nothing but no difference. Almost like the initial startup pellet dump doesnt know when to turn off. Any ideas?

 

[jzm2cc]

If the auger keeps feeding pellets non stop then it's the control box assuming you haven't made any wire changes. Auger driver chip can be obtained and easily replaced if desired.

 

[Burrn]

If the auger keeps feeding pellets non stop then it's the control box assuming you haven't made any wire changes. Auger driver chip can be obtained and easily replaced if desired.

No wire changes. Its only a problem at startup and I have been using my hand to block the pellets from dropping and overfilling the firepot. Also The weird thing is when I turn the heat to low after it runs for a while, it stops feeding until switched back to high, then it feeds again. I'm cleaning it all out for the cold season coming and will see how she runs after that. I have never blown air through vac hose that runs to auger so am going to do that but doubt thats my issue

 

[Former Farmer]

Turn the power off to the unit, then take and pull the control box out and reinstall. Make sure to reseat it evenly to make good contact. It is possible that it isn't fully seated or some of the pins maybe a bit dirty.

 

[jzm2cc]

Agree with Farmer, when module is repeated leave metal cover off so you can count blue blinks when plugged in, should see one blink per 10 seconds. Also initial feed seconds should be about 60 seconds, not infinity. When stove lights do you see green LED inside module after a minute or three of running? Eventually this turns to red indicating fire is up to temperature and normal feeding cycles begin for low, med, or high settings. Auger time will vary for each heat setting, hotter means more auger on time.

 

[Burrn]

Agree with Farmer, when module is repeated leave metal cover off so you can count blue blinks when plugged in, should see one blink per 10 seconds. Also initial feed seconds should be about 60 seconds, not infinity. When stove lights do you see green LED inside module after a minute or three of running? Eventually this turns to red indicating fire is up to temperature and normal feeding cycles begin for low, med, or high settings. Auger time will vary for each heat setting, hotter means more auger on time.

I have the 2000 model classic bay (20+ years old ) so no lights on control box right? I've never done more than just replaced a fuse in that area of the stove. But I'll try to unmount the box and remount and get a look in there. Thi s stove is old but so reliable and I'm determined to see her keep going

 

[Burrn]

If the auger keeps feeding pellets non stop then it's the control box assuming you haven't made any wire changes. Auger driver chip can be obtained and easily replaced if desired.

Any recommendations on where i could get auger driver chip and which chip that is in the bo

If the auger keeps feeding pellets non stop then it's the control box assuming you haven't made any wire changes. Auger driver chip can be obtained and easily replaced if desired.

I remounted the box and will give it another run tomorrow. If I need the chip after all, how would I go about finding one? Ive never seen (or had to look for) a diagram of the control box for the 2000 model CB 1200

 

[jzm2cc]

I can help you with auger chip, but let's confirm module is faulty first. If you have older gray control box it has green and LEDs on side of box, the newer translucent boxes have LED inside box that changes color from green to red, or yellow if thermocouple is bad.