Problems related to residential installations.
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I have a Carrier 58UHV060-12 Natural Gas furnace. The ICM blower module failed and was replaced. My first question is, if you apply power (120 VAC) to the terminals and leave the control plug ( communications ) REMOVED from the motor what should the motor do? Run at full speed or not run at all. Every where I have researched I have not found anywhere that it should run until you hook up common 24 VAC and G ( fan), but a local HVAC contractor tells me it should run. This answer will determine where I proceed from here.
I assume you have a 120 volt motor. First you need to be very careful what wires you use. Most motors have different wires (red, black etc) for the various speeds the motor will run at. There should also be a common, usually white. Also there may be a run capacitor in the circuit. If you connect the 120 volts between the common (usually white) and one of the other speed wires, the motor will run. All the 24 volt control circuit does is determine what speed the motor will run at by connecting the 120 volts via a relay to the appropriate motor wires. Your furnace should have a wiring diagram showing you exactly what wire controls what motor speed.
yes the motor is 120 Volt. This is a ICM ( or ECM , variable speed motor )not a PSC ( Permanent-split-capacitor) motor that I believe you are referring to. The ICM has a 5 pin connector for 120 / 240 volt operation by jumper on connector and a 16 pin plug for speed control. all relays are on the control board. and yes the furnace has a diagram as well as what I have downloaded along troubleshooting information. No where does it state what the motor will do if only power is applied.