Hybrid Heater Codes

Rheem · ProTerra 120V plug-in

Rheem ProTerra 120V plug-in error code T131

Clean Filter Reminder

What it means

Air filter routine maintenance reminder

Source: Residential 120V plugin Heat Pump Water Heater (Dedicated Circuit) Use & Care Manual, AP21914 Rev 02, page 31

Also listed in: Residential 120V Plugin With HydroBoost Heat Pump Water Heater (Shared Circuit) Use & Care Manual, AP22654 Rev 01, page 31

What Rheem says to do

1. Set mode to Electric or OFF. 2. Remove air filters and clean by washing with a mild detergent. 3. Dry air filter and reinstall. 4. Set unit to desired mode.

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