Hybrid Heater Codes

Rheem · ProTerra 120V plug-in

Rheem ProTerra 120V plug-in error code A009

Compressor wiring may be faulty

What it means

Heating source default to elements due to compressor malfunction

Source: Residential 120V plugin Heat Pump Water Heater (Dedicated Circuit) Use & Care Manual, AP21914 Rev 02, page 30

Also listed in: Residential 120V Plugin With HydroBoost Heat Pump Water Heater (Shared Circuit) Use & Care Manual, AP22654 Rev 01, page 30

What Rheem says to do

These steps involve electrical testing or parts replacement. Rheem's manuals tell owners to leave that work to a qualified service technician.

1. Check connections of the wiring and sensors. 2. Get an Ohm reading on the thermistors (if multimeter is available) (See Ohm chart for correct readings based on ambient temperature). 3. Check on display by selecting Service-->Sensors-->If sensor shows - 40°F, the circuit is open. +250°F indicates the circuit has shorted. Note: To confirm reading, power down the unit and unplug the thermistor from the board. Check Ohm reading. (See ohms chart)

Last checked 2026-10-03.

Safety first

From the manufacturer's manual for this series.

The same code on other models

Codes mean different things on different heaters. Match the series to the model number on your rating label.

Other ProTerra 120V plug-in codes