A.O. Smith All models error codes
Codes
- 1Error codeThermopile voltage too low - thermocouple or thermopile lead needs replacement, or gas valve connection is dirty
- 2Error codeIgnition failure - check for gas supply, pilot orifice blockage, or faulty igniter
- 3Error codeTemperature sensor fault - check thermistor resistance
- 4Error codeHigh-temperature lockout - unit reached 170°F (77°C).
- 5LED codeFlame sense issue - similar to 2 blinks but flame detected without a call for heat (ghost flame).
- 7Error codeGas valve electrical fault - internal solenoid or control board communication failure
- 12Error codeFlame failure
- 15Error codeThermistor fault
- 29Error codeNeutralizer fault
- 71Error codeGas solenoid fault
- 90Error codeCombustion abnormal
- C1Error codeCombustion blower fault
- C02Error codeIncorrect reference voltage from the AD converter
- C2Error codePressure switch fault
- C3Error codeIgnition failure
- C4Error codeFlame sensor fault
- E01Error codeHot/cold sensor fault
- E1Error codeWater temperature exceeds safe limits
- E2Error codeThermostat is malfunctioning or not communicating
- E03Error codeEvaporator sensor fault
- E3Error codeFlame sensor issue; inadequate flame detected
- E04Error codeCompressor over-temperature
- E4Error codeHigh-temperature limit switch activated
- E05Error code
- E5Error codeWater heater fails to ignite; gas supply issue
- E6Error codeOverheating; requires immediate attention
- E07Error codeDefective pump
- F01Error codeUpper/lower element fault
- F02Error codeDirty or blocked fan
- F03Error codeThermostat fault
- F04Error codeNo burner pressure
- F07Error codeDefective gas valves
- F08Error codeFlame detection before the gas valve opened
- F09Error codeTemperature T1, T2 or T3 is greater than 99oC
- F10Error codePressure switch not closing
- F11Error codeDefective gas valves
- F16Error codeBlocked vane switch
- G2Error codeDiamètre évacuation en air Hauteur évacuation des gazmètre de l’appareil
- H1Error codeGas proportional valve
- H2Error codeFlow sensor
- han18Error code• If the SW1 #6 dip switch is configured for LWCO present when the optional control is not installed on the boiler. This will return a “Low Water” error message.
- han90Error code• Perform Power Supply Test Procedure (page 40) - correct any problems indicated by test.
- HPT-60Error codeResidential Hybrid Electric Heat Pump Water Heater
- J11ParameterThis circuit can be used to enable/disable boiler with a supervisory control for: night setback, occupied/unoccupied, freeze protection, lead/ lag of multiple boilers. This circuit can also be used with a standard aquastat.
- J23Error code
- J24Error codeSee pages 13 and 34. • Close visual inspection of J24 plug/socket con- nection on MCB Daughter Board. See page 34.
- Low24Error codePerform this test with the wiring harness plugged into the J1 Socket. • Secure power to boiler; temporarily disconnect load wiring from secondary coil on transformer.
- off120Error code(standard Cat 5 net- work cable). Plug UIM comm cable into other “internal” comm port on the MCB (page 32). • Closely inspect communication ports on MCB and UIM for damage or wear (page 32). Hot wire to terminal 8, neu- tral wire to terminal 9 (page 36). If not present check wiring from PDB J1 socket. Perform this test with the wiring harness plugged into the J1 Socket.
- S01Error codeSensor is not (correctly) connected
- S02Error codeSENSOR ERROR