What should I do if my Ruud Ultra Plug-in Heat Pump with HydroBoost (120V Shared Circuit) shows Alarm Code T009?

CAUTION: For your safety, DO NOT attempt repair of electrical wiring, controls, heating elements, or other safety devices. Refer repairs to qualified service personnel.

Possible Cause: Heating source defaults to elements due to compressor malfunction. What To Do:

1. Check connections of the wiring and sensors.
2. If you have a multimeter, get an Ohm reading on the thermistors. Refer to the Ohm chart for correct readings based on ambient temperature.
3. On the display, navigate to Service –> Sensors. If the sensor shows -40°F, this indicates the circuit is open. A reading of +250°F signals that the circuit has shorted. To confirm this reading, power down the unit and unplug the thermistor from the board, then check the Ohm reading again.

This answer is applicable for the following model: Ruud Ultra Plug-in Heat Pump with HydroBoost (120V Shared Circuit).