320386-001 - AO Smith Water Heaters

STATUS LIGHT AND DIAGNOSTIC CODE TROUBLESHOOTING CHART (Continued)LED STATUS PROBLEM CORRECTIVE ACTION4 FLASHES The Gas Control Valve’stemperature sensor has detectedthat the water temperature wastoo high. Once this conditionoccurs, the Main Burner andthe Pilot Light will be shut off.Since the Pilot light will be off,should this condition occur, thisFlash Code will only be displayedimmediately after the Pilot hasbeen relit. Turn Gas Control Valve/Thermostat knob to OFF.5 FLASHES The temperature sensor(thermistor) is defective.Relight pilot and verify 4 flashes. If 4 flashes areobserved, turn Gas Control Valve/Thermostat knobto OFF. Turn Main Gas Supply OFF. Replace theGas Control Valve/Thermostat. See “Removing andReplacing the Gas Control Valve/Thermostat.”Turn Gas Control Valve/Thermostat knob to OFF.Replace the temperature sensor (thermistor).7 FLASHES Gas Control Valve failure. Turn Gas Control Valve/Thermostat knob to OFF. TurnMain Gas Supply OFF. Replace the Gas Control Valve/Thermostat. See “Removing and Replacing the GasControl Valve/Thermostat.”8 FLASHES This condition only appears if thegas control/temperature knob hasbeen turned off and the thermopilecontinued to produce electricpower. This condition can occurif the thermopile does not cooldown as quickly as expected whenthe unit is shut off. This conditioncan also occur if the gas control/temperature knob has been turnedoff and the pilot continues tooperate because the pilot valve isstuck in the open position.Make sure that the gas control valve/thermostat knob isset to OFF. Wait one minute. Remove the outer door.Look through the sight glass for a pilot flame. If a pilotflame is observed with the gas control valve/thermostatknob set to the OFF position, the pilot valve is stuck open.Turn the main gas supply OFF. Replace the gas controlvalve/thermostat. For instructions, see “Removing andReplacing the Gas Control Valve/Thermostat.”If the pilot flame is not observed when the gas controlvalve/thermostat knob is set to the OFF position, wait 10minutes for the thermopile to cool, then attempt to relightthe pilot by following the lighting instructions on the waterheater’s label. If this condition returns, replace the gascontrol valve/thermostat. See “Removing and Replacingthe Gas Control Valve/Thermostat” for instructions.34