Heat Pump: YZH
Re: Outdoor Fan not Operating
YZH heat pumps are equipped with a YorkGuard VI module which monitors and controls unit operation and defrost.
The factory-installed outdoor fan motor is an ECM motor with a remote motor module controlled by a direct 24VAC signal.
- The motor module receives constant 230VAC power.
- 24V + (Blue) comes off of the compressor contactor to the motor module.
- 24V Com (Yellow) comes off of "C" to "L1" and out "ODF" (all on the Yorkguard) to the motor module.
| Qty |
Possible Causes: |
|
Bad Motor/Module |
|
Bad Yorkguard VI |
|
Defrost Mode |
| 1 |
Stuck Contactor |
CHECKOUT:
1. Check Outdoor Unit
- Make sure the thermostat is set correctly and calling for either Heating or Cooling.
- Remove the access panel of the outdoor unit.
- Compressor and Outdoor Fan Operating Correctly → Step 3. Check Compressor Contactor
- Compressor Operating with No Outdoor Fan ⇒ Continue
- Check for 24VAC across the Compressor Contactor coil.
- No Power + Compressor Operating = Stuck Compressor Contactor
- Power Present + No Outdoor Fan → Step 2. Check Fan Motor
2. Check Fan Motor
- On theYorkguard VI module, check for 24VAC between "M" (Gray) and "L1" (Yellow).
- No Power = Bad Wire/Wiring ⇒ Make sure Yellow wire is connected between "C" and "L1".
- Power Present ⇒ Check for 24VAC between "M" (Gray) and "ODF" (Yellow).
- No Power = Bad Yorkguard VI or Defrost Mode
- Power Present + No Outdoor Fan Operation = Bad Motor/Module
3. Check Compressor Contactor
- Check for 24VAC across the Compressor Contactor coil.
- No Power + Compressor Operating = Stuck Compressor Contactor