What steps are recommended if my Ruud Ultra Plug-in Heat Pump with HydroBoost (120V Shared Circuit) presents Alarm Code A106?

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 heat pump temperature malfunction. What To Do:

1. Conduct a thorough inspection of the wiring and sensors connections, ensuring they are secure.
2. If a multimeter is accessible, obtain the Ohm reading on the thermistors. Be sure to cross-reference with the Ohm chart to understand readings in the context of the current ambient temperature.
3. On the device’s interface, proceed to Service –> Sensors. A reading of -40°F indicates an open circuit, whereas a +250°F reading denotes a shorted circuit. For confirmation, switch off the unit, disconnect the thermistor from its board, and recheck the Ohm value.

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