Blower motor stopped, there is a medium-loud ''electric buzz'' sound every minute or so as if trying to start the blower motor. Could be relay switch. Last week, I extracted the entire motor and fan assembly (the one in the bottom of the furnace that drives the air through the house duct system). The motor was pretty filthy, so I took the entire thing apart an blew out all the dust, cleaned up the motor, Zoom oiled the bearing assemblies at each end, put it all back together. Started up and ran great for 2 days, then quit again - so I don't think it's the motor. Could be an electric part. Any ideas? I'm unfamiliar with furnaces, but good with my hands
Heating & Cooling - Bryant
Answers & Comments
You have a bad "starting capacitor" .. the capacitor is used to get the motor to start in the correct direction .. when its bad the motor doesnt know which way to turn so it just sits there buzzing until it gets hot .. that trips a thermal breaker in the motor and shuts it off ... when it cools it tries again .. dont let it do that for a long time since you could damage the moter eventually ... the starting cap is a round cyclinder probably mounted close to or on the motor (wires come from it to the motor) .. they are not expensive .. you can take the old one with you to a motor parts place so they can match it up with a new one ..
while the motor is buzzing .. if you spin the blower it will start in whatever direction you spin it ... it will run until its shut off but then wont start on its own again ... changing the starting cap will fix that ..