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A.O. Smith Service Manuals & Error Codes
14Service Manuals
37Error Codes
1Appliance Types
A.O. Smith Appliance Types
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Top Error Codes for A.O. Smith
CodeTypeDescription
031Water HeaterIncorrect dipswitch settings on the computer board.1Water HeaterCommunication error between the upper (electronic control display) and lower...10Water HeaterAir pressure switch contacts remain open longer than 5 seconds after the...101Water HeaterAbnormal combustion detected by the air-fuel ratio detection system.11Water HeaterFlammable Vapor Sensor is open.111Water HeaterIgnition failure — heater does not fire after three failed attempts at ignition.12Water HeaterFlammable Vapor Sensor is shorted.121Water HeaterFlame loss — flames disappear while the unit is still supposed to be in...13Water HeaterTemperature sensor (thermistor) inside the immersion probe is open.14Water HeaterTemperature sensor (thermistor) inside the immersion probe is shorted.15Water HeaterOne or both temperature adjustment buttons are stuck.16Water HeaterNo current to Power Anode (P-ANODE OPEN).17Water HeaterPower Anode circuit failure.2Water HeaterSelf-diagnostic tests have found a problem with an internal circuit.3Water HeaterIgnition/flame failure - water heater has reached maximum number of retries and...