Carrier 58STA110 Inducer Motor won't shut off

Zonks

During last winter I lost the control board (Moisture from the previous cooling period) for this unit built in 2004. It was still under warranty so I had it replaced. All worked good until we recently switched over to using the air conditioner. In the cool mode, the Inducer motor runs continuously. The air conditioner functions properly like this, but it's probably not good for the motor. I also found out that now I can only get the air conditioner to kick on if I have the fan in the on position instead of the auto position. I'm suspecting something on the control board is either bad or miss-wired. Anybody have a clue where to start.

Thanks!

beenthere

Look where the stat wires are connected. And post that info.

Zonks

Here's how the thermostat wires come into the board:
Green wire connected to G Terminal
Blue wire connected to Com 24V
White wire connected to W
Yellow wire connected to Y
Red wire connected to R

The wires out to the Air Conditioner outside are the following:
White wire connected to com 24V
Red wire connected to Y Terminal

beenthere

Disconnect the white wire from the W terminal on the board. And see if the A/C works without the inducer then. If so, its your stat.

Zonks

With the white wire removed, the airconditioner operates normally (Even when the fan is in the Auto Position) but it has no affect on the Inducer motor. Even with the white wire removed the motor basically runs whenever the door switch is pushed in. I even did the component check described in the manual and the Inducer motor ran thru the entire check when it was supposed to shut off after the test.

Do you think we are looking at another bad board?

beenthere

Its possible the board has a stuck relay for the inducer.

Did the inducer run continuous all winter after the board was replaced? If not. Its also possible, the high limit has tripped and did not reset.

Does the heat still work if you set the thermostat to heat and turn it up. If not, the high limit is tripped. Which could have been caused by a dirty air filter.

If the limit isn't tripped. Then the board is probably bad.