HVAC/Electric motor Question?

cruiseroutfit

Cruizah!
Moderator
Vendor
Location
Sandy, Ut
We have a 50+ year old home, and the furnace has to at least be from the 70's mabey older. That said it has worked great since moving in a couple years ago. Tonight I smelt a little "burning" smell throughout the house. Almost smelt electrical... but almost a "dusty" smell like when you turn on your furnace for the first time each season. I looked around and found the culprit was in deed the furnace. I opened up the service access, everything looked OK. I felt the blower motor and it was insanely hot, too hot to touch and the smell was coming from it. It was not spinning at all, but I could spin the fan by hand, so the bearings were not seized. No brainer, shut it off and pull the motor for replacement or repair right?

I let it cool down before working on it. Just to troubleshoot a little more I hooked up my multimeter to the blower fan motor feed lines and verified it was getting power at the times it was supposed to. Just like it should the power kicked on a short time after the burners turned on, however this time the fan popped right on and worked just fine, no excess heat, no noise, just worked fine?

What should I do? I'm thinking I should pull it and have it looked at. Any recommended motor shops?
 

jet_aj

Just loosing my mind
Location
UT
I've seen many older furnace motors that are filled with dust/lint, animal hair or whatever else floats through the average house. I'd say if it is working it might be a good idea to just pull it out and clean it out. I usually just use a paint brush and even compressed air to clean it out. while you have it out clean the blower fins... dirt will tend to build up on the fins and will significantly affect the cfm the blower will push. If the fins are too dirty it can really affect your heating bill because the furnace will have to run much longer than needed to heat your house. If your really concerned about the motor shutting down on you again it can be worth just replacing it. If you pull it out and take it into pretty much any HVAC company they should have a replacement. Depending on the motor and furnace brand your probably only talking around 50-75 bucks for a new motor.
 

cruiseroutfit

Cruizah!
Moderator
Vendor
Location
Sandy, Ut
Thanks for the reply Jeremy.

It heated up really bad again yesterday, so this morning I pulled it and swapped it for a new motor. It was a bit pricier than I hoped (this one is old & rare) but it working great again.
 

SAMI

Formerly Beardy McGee
Location
SLC, UT
Glad you found one locally. You probably ended up paying close to what we could next day air one in for you.

... Bring me a real motor next time ;)
 
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gijohn40

too poor to wheel... :(
Location
Layton, Utah
there is a little shop on west temple and about 3200 south called stephens that does excellent work on electric motors.. they even can rewind one for you if you wanted to...

My company (electricians) use it all the time for electrical motors that are having a hard time...

I have even taken drills and rotozip motors in and they fixed them...
 
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