OT unable to locate starting capacitor

[parris]

The title pretty much says it all. my old furnace motor started acting up tonight and hums without starting.

I checked for a starting capacitor both on the motor and the fan housing. I for the life of me can't locate one. The furnace in question is quite old and pretty straight forward in layout.

The blower motor is 1/6 hp not direct drive. Did any of these ever come with internal capacitors? The replacement cost for the motor's not very high but I don't want to just assume that it's the motor that's packed it in.

Thanks for any help.

[AngryScientist]

can you get to the shaft to turn it by hand? if it's the start capacitor, you should be able to give it some torque by hand and get it going. that might be a good place to start?

[Louis]

At this time of year, with the weather we're getting these days, I wouldn't mess with fancy trouble-shooting. I'd replace the motor with new one, then play around with the old one at my leisure.

[AngryScientist]

Originally Posted by Louis

At this time of year, with the weather we're getting these days, I wouldn't mess with fancy trouble-shooting. I'd replace the motor with new one, then play around with the old one at my leisure.

absolutely. parris is in upstate NY too. it's cold up there.

[parris]

Angry I did that a few minutes ago just because like most of us I can't leave things alone. It does turn but very stiffly.

Louis you're right I'll try to find one in town tomorrow and get it installed tomorrow night once I'm home from work.

I just checked again and I've got a feeling that if there is a capacitor it's internal to the motor because there's just nowhere else for one to be. from what i can look at.

[Frankwurst]

Originally Posted by AngryScientist

can you get to the shaft to turn it by hand? if it's the start capacitor, you should be able to give it some torque by hand and get it going. that might be a good place to start?

I've done this on my parents old furnace a couple of years ago. Happened on a weekend made big machine go and set the fan on constant until their mechanic could get in on monday to check the starting capacitor which was bad. If it is a bad capacitor it doesn't take much to give it enough of a boost to make it go. On the other hand if there is no capacitor I've had the same technique work on older electric motors. Worth a try.

Never mind. To late

[Frankwurst]

Originally Posted by parris

Angry I did that a few minutes ago just because like most of us I can't leave things alone. It does turn but very stiffly.

Louis you're right I'll try to find one in town tomorrow and get it installed tomorrow night once I'm home from work.

I just checked again and I've got a feeling that if there is a capacitor it's internal to the motor because there's just nowhere else for one to be. from what i can look at.

Never mind my reply. Sounds like a bad bearing now.

[AngryScientist]

i dont like the sound of that parris. a fan motor combo should spin nice and freely. you may have a bad bearing somewhere. hopefully if you do, it's in the motor, not the fan.

obviously, once you pull the motor you can spin the fan and see how it feels.

tough time of year to have to work on this stuff under the pressure of frigid temps. stay warm tonight pal!

[AngryScientist]

ha, frank and i are on the same page here.

[parris]

Thanks for your replies and such. I'm lucky in that it's warming up over the next couple of days AND we have a decent back up heat source so the house won't get too cold.

I'm just a little surprised in how fast this happened. Maybe it's been going on for a while and we didn't notice but our house is a smallish ranch where we generally hear the others in the house change their mind!

[Frankwurst]

Originally Posted by AngryScientist

ha, frank and i are on the same page here.

Yeah shade tree furnace/electric motor mechanics. I had problems with our furnace this year as well. It was sub zero temperatures and involved the ignition and fire cycle. Thought I had it figured out but the next day it acted up again. I finally got it where I thought it was O.K but called someone that actually knows furnaces to come in and check it out just to make sure. I don't like being out in sub zero temps and I damn sure don't want them coming into our home.

[parris]

I've got the info off the motor plate, mounting bolts are loose, belt is removed, and will be calling around for a replacement today.

It is the motor the bearings are very stiff and tight. I'm surprised it ran as well and as long as it did in that condition. Thanks again for all the advice and help!

[Louis]

Fallback blower option if you can't find a replacement motor:

[Peter B]

Originally Posted by Frankwurst

<snip>
... and involved the ignition and fire cycle.

Originally Posted by Louis

Fallback blower option if you can't find a replacement motor:

Glad parris got his heat sorted.


I opt for a simpler, if more laborious, ignition and fire cycle.

[Louis]

Originally Posted by Peter B

I opt for a simpler, if more laborious, ignition and fire cycle.

Wood stoves are great, but labor-intensive. I have a propane Jøtul in my living room and really like it (except for a few niggling issues). The best part (other than not having to feed it manually) is that it has a remote thermostat that allows me to "set it and forget it."

The only real problem is getting the heat from the living room to the rest of the house, which is tough to do if you don't have power to run the forced-air system.

Same model as mine: