My Trane Gaspack fan won’t run. All I am getting is a slight humming sound in the return duct. There was also a faint burning smell in the house that led me to the problem. I was glad to figure it out before bedtime last night, but now it’s 50 degrees in here.
Am I due for a new motor, or will I get lucky and just need a new capacitor or other minor component? System is about 15 years old. Is it time for a major upgrade?
Need to get this resolved pretty quickly. Forecast is for 17 degrees tomorrow night.
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Been there, done that. Yes, you'll need a new blower motor. Fifteen years is a decent lifespan for a blower motor, especially if it's used for central AC also. When mine died, I was able to [CAREFULLY] spin the blower cage by hand to help it start, which gave some heat until it cycled off. I'd get on the phone ASAP and get someone in to replace it. The motor and installation for my Carrier system cost $350.00 in 01/2004.
That is a simpton of a bad starting system.Which might be just a bad cap. But if could be burnted out starting winding, or centrifigal switch.If you try and fix it yourself clean the contacts on the centrifical switch.If you can work on it yourself it is certainly worth trying that as a fix.But if you have to all out a serice tech then, at that age, replace is probably the way to go.
So my two 29-year-old blower motors died 14 years ago?
That's right, Dan, you'd better get on it right away.
Had the same hum from my furnace motor. Left it off till it cooled down then it restarted. I was able to oil the bearings on my motor, took the plugs out of either end and added some light oil. This solved the problem until it got warmer and I changed the motor out.
As I suspected...
Actually, the motor was failing to start with the normal cycling of the thermostat a few weeks ago. If I left the fan running continuously, it would work.
When it finally stopped on Saturday, I was actually tipped off by a faint burning smell inside of the house. A little investigation revealed no airflow in the HVAC, and then I discovered the humming fan motor.
I shut the system down at the thermostat (Heat OFF, Fan on AUTO). No more humming. No more burning smell. I don't have time to deal with this right now, so I'm in a chilly holding pattern.
I just walked by the unit outside, and I had some heat coming from the chimney on the unit. I don't understand this, as the T'stat is turned OFF. Shouldn't the burner be OFF?
There was not a lot of heat, but more than I want to pay for when I'm not getting heat inside.
First get in there and see if the motor turns freely. Probably not. Unless it's something (eg, a dead mouse) blocking the motion of the squirrelcage, it's probably a bad bearing.
Sometimes you can briefly revive a bad bearing by force-feeding it light oil. (Works better if the bearing is a bit warm when you do this.) But once the bearing has failed like this it's not long for this world -- either rebuild or buy a new motor.
The other types of failures you can see are bad windings, bad start switches, and blown start capacitors. If you can spin the motor and then apply power (with it spinning) and the motor starts OK then it's one of these types of failures. The bad start capacitor fairly likely, and replacing it is fairly straight-forward. A bad start switch requires disassembling the motor slightly and at least filing the contacts (though that's not a permanent fix). If a winding is blown then it's time for a new motor.
I assume this is direct-drive (vs belt driven). If belt driven, and the unit doesn't turn freely, remove the belt and find out which piece is stiff. Replacing the shaft bearings in a belt-driven unit is a PITA but quite practical.