Trane blower question

HVAC dummy · 07-05-2010, 07:06 AM

I have a Trane TUC080B9V3A0 with the variable speed blower. The blower quit while using AC, and the lines to the outside compressor were iced up and the unit still running. Iced up because of no airflow past A coil in plenum?

Blower was removed from furnace. Motor appeared to spin freely, but 10A cartridge fuse in motor control on end of motor was blown. New fuse blew again when fan was set to on at thermostat. There is 115V to the motor controller when trying to run fan from the thermostat.

How do I determine if I should replace the motor, the controller, or both? Is this a DC motor? How do I just check to see if the motor is still OK? Thanks

**beenthere** · 07-05-2010, 09:19 AM

Ohm the leads from the motor.

HVAC dummy · 07-05-2010, 09:35 AM

Quote:

Originally Posted by beenthere

Ohm the leads from the motor.

I think there were 4 spade terminals in the connector from the controller to the motor. How are they pinned out? Thanks

**beenthere** · 07-05-2010, 12:43 PM

Should only be 3 wires from the motor to the module.

Black red green.

Check ohms between each.

HVAC dummy · 07-05-2010, 03:38 PM

Quote:

Originally Posted by beenthere

Should only be 3 wires from the motor to the module.

Black red green.

Check ohms between each.

There are 5 total in a connector from the module that plugs directly into the motor. 2 brown, and a red, a black, and a blue. There is 4 ohms between the red, black, and blue in any combination of terminals, and there is .5 ohms between the 2 brown. There is no continuity between either brown, and either the black, red, or blue.

Is this a DC motor? I haven't taken the motor out of the 3 legged bracket to try to read a tag on it.

Thanks for any help.

**beenthere** · 07-05-2010, 05:51 PM

Ok. You don't have a VS blower then. Thats not a DC motor.

Does the one brown wire have a white stripe.

HVAC dummy · 07-05-2010, 07:15 PM

Quote:

Originally Posted by beenthere

Ok. You don't have a VS blower then. Thats not a DC motor.

Does the one brown wire have a white stripe.

Neither brown wire has a tracer. The schematic on the inside of the blower compartment cover says: integral fan control, variable speed motor. I'm getting warmer, and need my air back! Thanks

**beenthere** · 07-05-2010, 07:20 PM

How old is your furnace?

HVAC dummy · 07-05-2010, 09:33 PM

Quote:

Originally Posted by beenthere

How old is your furnace?

I honestly don't know, and I couldn't find any date on the info tag inside the furnace. I don't want it to be time for a new one just yet.

**beenthere** · 07-05-2010, 09:36 PM

Post serial number.

Yours could be an early version VS. They generally came with a 5 year warranty.

HVAC dummy · 07-05-2010, 11:12 PM

Quote:

Originally Posted by beenthere

post serial number.

Yours could be an early version vs. They generally came with a 5 year warranty.

d49638140

**beenthere** · 07-06-2010, 12:03 AM

I think its a 96.

First generation VS. 2.0 version. If its older then that, it real expensive.

Can you post a pic of the motor.

HVAC dummy · 07-06-2010, 09:24 PM

Quote:

Originally Posted by beenthere

I think its a 96.

First generation VS. 2.0 version. If its older then that, it real expensive.

Can you post a pic of the motor.

I'm having trouble posting pictures, but here's the data from the tag on the motor:
GE ECM model 55ME39HG LX23 S programmable motor

1/2 hp 115V 8A 60hz rpm1100

equip mfrs# C143810P02

Hope this helps. Now that the motor is out of the housing, and the cage is off, the motor seems to be harder to turn. It doesn't spin freely. So it's probably no good? Thanks

**beenthere** · 07-07-2010, 07:13 AM

VS motor should spin freely. It uses permanent magnets. So it should feel like it has rough bearing when you spin the shaft by hand.

It is more likely that the controller is out.

Trane had a test diagram for that motor. But I don't have a copy of it. You might be able to find a copy floating around on the internet.

HVAC dummy · 07-07-2010, 07:34 AM

Quote:

Originally Posted by beenthere

VS motor should spin freely. It uses permanent magnets. So it should feel like it has rough bearing when you spin the shaft by hand.

It is more likely that the controller is out.

Trane had a test diagram for that motor. But I don't have a copy of it. You might be able to find a copy floating around on the internet.

Thanks for all of your help. From the info that I have been able to find, I've discovered that the parts are expensive. I think I'm much further ahead by just getting a new furnace this year while I can recoop 30% of the cost with an energy tax credit. I haven't been able to find much info on this furnace online, but if you happen across the test diagram, I'd be interested in seeing it. Thanks again for all of your help.