TEV - Flashing Code 5/LT2 Fault - Heating

ClimateMaster Heat Pump: Heating

Re: Code 5 / FP2 Fault

Code 5 = Low Air Coil Temperature (FP2)

► There should be no normal reason for an FP2 Fault in the Heating mode. LT2 should only get cold in the Cooling mode.

• The FP2 thermistor temperature must be below the selected low temperature limit setting (30 deg. unclipped) for 30 continuous seconds during a compressor run cycle to be recognized as a FP2 fault.
• The FP2 input is bypassed for the initial 120 seconds of a compressor run cycle.
• FP2 is set at the factory for one try. Therefore, the control will go into lockout mode once the FP2 fault has occurred.

CHECKOUT:

1. Check Operating Conditions

• If available, connect a Climatemaster communicating thermostat to the unit.
• Go into Service Mode by holding the Up & Down arrows for 5 seconds.
• Select Diagnostic Mode.
• Start the unit in heating mode.
• Monitor the following temperatures:
  • LT1
  • LT2
  • Leaving Air Temperature
    • LT2 Temperature Starts & Stays Low = Bad FP2 Sensor
    • ​​​​​​​​​​​​​​​​​​​​​Leaving Air Temperature Drops + LT2 Temperature Drops = Reversing Valve in Cooling Position
    • Leaving Air Temperature Increases + LT2 Temperature Drops ⇒ Check for Reversed Sensor Wiring ⇒ Check Actual Sensor Wiring Compared to Diagram