Rheem Electric Water Heaters Error Codes


Commercial Electric Water Heaters 9kW – 900kW Input Models

There are seven error messages that can be displayed in response to software or hardware problems with the boiler’s internal electronic temperature control. The error codes that may be seen flashing on the display are:

SF – Sensor Failure
The display flashing SF indicates an out-of-range or defective sensor. Make sure sensors are properly installed, wired and  connected to the control. Correct sensor installation or replace sensor.

EF- EEPROM Failure
The values read form the EEPROM are not the same as the values written into the EEPROM. This error cannot be field repaired. Replace the water heater’s electronic temperature control.

CF – Calibration Failure
The calibration resistor reading was not within the range of the Analog to Digital converter. This error cannot be field repaired. Replace the water heater’s electronic temperature control.

OF – Stray Interrupt Failure
An unused interrupt occurred. This error cannot be field repaired. Replace the water heater’s electronic temperature control.

CE – Configuration Error
The device hardware was configured to a nonexistent device. This error cannot be field repaired. Replace the water heater’s electronic  temperature control.

OE – ROM Error
The internal ROM of the microprocessor in the boiler’s electronic temperature control is defective. This error cannot be field repaired. Replace the water heater’s electronic temperature control.




AE – RAM Error
The internal RAM of the microprocessor in the boiler’s electronic temperature control is defective. This error cannot be field repaired.  Replace the water heater’s electronic temperature control.

 LargeVolume Use and Care Manual PDF

Commercial Point of Use Electric Water Heater Trouble Shooting Guide

Commercial Point of Use Electric Water Heater Trouble Shooting Guide

Commercial Point of Use Electric Water Heater Trouble Shooting Guide

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