Rheem 305, 505, 705 Error Codes

11 codes from pages 10–12 of the manual

This is the list of fault, error codes the Rheem manual gives for the 305, 505, 705 tankless water heater. Find your code below and open it for what the manual says about its causes and what to do.

Fault codes from p. 10

CodeWhat it meansPage
14 Thermal Fuse p. 10
16 Over Temperature Warning p. 10
32 Outgoing Water Temperature Sensor Fault p. 10
33 Heat Exchanger Outgoing Temperature Sensor Fault p. 10
34 Combustion Air Temperature Sensor Fault p. 10
52 Modulating Solenoid Valve Signal Abnormal p. 10
61 Combustion Fan Failure p. 10
71 SV0, SV1, SV2, and SV3 Solenoid Valve Circuit Fault p. 10
72 Flame Sensing Device Fault p. 10
LC Scale Build-up in Heat Exchanger (when checking maintenance code history, "00" is substituted for "LC") p. 10

Error codes from p. 12

CodeWhat it meansPage
00 An "LC" or "00" error code indicates the unit is beginning to lime up and must be flushed. p. 12

Codes and descriptions are taken from the manufacturer’s manual; page numbers link to the PDF. ManualLib is not affiliated with Rheem. Found a mistake? Report an error.