Classic Bay 1200i combustion blower

[brs32]

Greetings,
Been a long time user of the forums - am pretty comfortable with all aspects of pellet stoves - have rebuilt a number of quads and Harmons. Was prepping my CB1200i this year with cleaning etc. - and noticed what looks like some burn marks on the side of the motor for the combustion blower. I may well end up ordering a replacement out of due diligence. However the blower runs normally - no sounds or abnormal issues - just these marks. It looks like it could also be just dust/debris hitting the body as the fan is spinning. Haven't really had any issues with burnt up motors- usually just bearings. So does this look like a problem? What would the tell tale signs of a motor failing or about to fail look like? Would a resistance check help to determine the health of this fan? I have two quads - so like to keep an inventory of viable parts on hand. Thanks.

 

[Whitenuckler]

Greetings,
Been a long time user of the forums - am pretty comfortable with all aspects of pellet stoves - have rebuilt a number of quads and Harmons. Was prepping my CB1200i this year with cleaning etc. - and noticed what looks like some burn marks on the side of the motor for the combustion blower. I may well end up ordering a replacement out of due diligence. However the blower runs normally - no sounds or abnormal issues - just these marks. It looks like it could also be just dust/debris hitting the body as the fan is spinning. Haven't really had any issues with burnt up motors- usually just bearings. So does this look like a problem? What would the tell tale signs of a motor failing or about to fail look like? Would a resistance check help to determine the health of this fan? I have two quads - so like to keep an inventory of viable parts on hand. Thanks.

If you can get a look at the windings themselves with a different camera angle, or visual with a light, that might show something. I'd replace it and look at it on the bench. If the winding overheated the coating on the copper winding will change color. The resistance could still check OK, but the insulation could be damaged. Better to change it in case it decides to overheat leading to other faults.

 

[brs32]

If you can get a look at the windings themselves with a different camera angle, or visual with a light, that might show something. I'd replace it and look at it on the bench. If the winding overheated the coating on the copper winding will change color. The resistance could still check OK, but the insulation could be damaged. Better to change it in case it decides to overheat leading to other faults.

Thanks for the input- when the new one arrives I'll put the old one the bench for dissection and report back in.

 

[Whitenuckler]

Thanks for the input- when the new one arrives I'll put the old one the bench for dissection and report back in.

Yes please do. I don't know your setup, but on mine you take the blower wheel off from inside the stove first in order to remove the combustion motor. On my recent cleaning I tried to get the set screw out and it didn't budge with a normal hex key. I gave up and now have a 1/4" socket hex set and will try again on another cleaning. I wanted to put my spare wheel on with some anti-seeze on the set screw.
If I can't get the wheel off I would need to cut the shaft off the motor. I guess I waited too long or wrong tool.

Another check on your winding is to ground. You might not see the heating as the heat builds up inside more than the outside. You can run your blower in a test setup and measure the amps. I think with those small motors they can stall or be overloaded and not blow the main fuse. In that case it will overheat. I have a separate fuses for all of my circuits now. That motor I fused at 2 amps.