Manufacturer error-code directory
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24 matching results
F.0Vaillant · Gas boiler · United KingdomFlow temperature sensor interruptedThe electrical signal from the flow temperature sensor is interrupted. Vaillant uses F.0 as a diagnostic fault code…F.1Vaillant · Gas boiler · United KingdomReturn temperature sensor interruptedThe electrical signal from the return temperature sensor is interrupted. Vaillant uses F.1 as a diagnostic fault code…F.10Vaillant · Gas boiler · United KingdomFlow temperature sensor short circuitThe flow temperature sensor circuit has short-circuited. Vaillant uses F.10 as a diagnostic fault code across applicable boiler…F.11Vaillant · Gas boiler · United KingdomReturn temperature sensor short circuitThe return temperature sensor circuit has short-circuited. Vaillant uses F.11 as a diagnostic fault code across applicable boiler…F.12Vaillant · Gas boiler · United KingdomHot-water temperature sensor short circuitThe domestic hot-water connection temperature sensor circuit has short-circuited. Vaillant uses F.12 as a diagnostic fault code across…F.13Vaillant · Gas boiler · United KingdomCylinder temperature sensor short circuitThe cylinder temperature sensor circuit has short-circuited. Vaillant uses F.13 as a diagnostic fault code across applicable boiler…F.20Vaillant · Gas boiler · United KingdomSafety thermal cut-out operatedThe safety thermal cut-out has operated and shut the boiler down. Vaillant uses F.20 as a diagnostic fault…F.22Vaillant · Gas boiler · United KingdomLow system water pressureThe boiler has detected low water pressure in the heating system. Vaillant uses F.22 as a diagnostic fault…F.23Vaillant · Gas boiler · United KingdomFlow and return temperature spread too greatThe temperature difference between the heating flow and return is too great. Vaillant uses F.23 as a diagnostic…F.24Vaillant · Gas boiler · United KingdomTemperature increasing too quicklyThe boiler temperature is increasing more quickly than expected. Vaillant uses F.24 as a diagnostic fault code across…F.25Vaillant · Gas boiler · United KingdomFlue-gas temperature too highThe monitored flue-gas temperature is too high. Vaillant uses F.25 as a diagnostic fault code across applicable boiler…F.27Vaillant · Gas boiler · United KingdomFlame signal detected while burner is offA flame signal has been detected even though the burner should be off. Vaillant uses F.27 as a…F.28Vaillant · Gas boiler · United KingdomNo flame signal during ignitionNo flame signal was detected during the ignition phase. Vaillant uses F.28 as a diagnostic fault code across…F.29Vaillant · Gas boiler · United KingdomFlame extinguished during operationThe boiler could not reignite after the flame was lost during operation. Vaillant uses F.29 as a diagnostic…F.32Vaillant · Gas boiler · United KingdomFan faultThe boiler has detected a fan fault. Vaillant uses F.32 as a diagnostic fault code across applicable boiler…F.35Vaillant · Gas boiler · United KingdomAir or flue pipe blockedThe boiler has detected a blocked air or flue route. Vaillant uses F.35 as a diagnostic fault code…F.52Vaillant · Gas boiler · United KingdomMass-flow sensor faultThe boiler has detected a fault with the mass-flow sensor or Venturi. Vaillant uses F.52 as a diagnostic…F.53Vaillant · Gas boiler · United KingdomCombustion regulation faultThe combustion-regulation system has detected a fault. Vaillant uses F.53 as a diagnostic fault code across applicable boiler…F.54Vaillant · Gas boiler · United KingdomGas supply faultThe boiler has detected insufficient gas supply, typically alongside F.28 or F.29. Vaillant uses F.54 as a diagnostic…F.57Vaillant · Gas boiler · United KingdomIncorrect combustion in comfort modeThe boiler is not burning correctly while operating in comfort mode. Vaillant uses F.57 as a diagnostic fault…F.62Vaillant · Gas boiler · United KingdomDelayed flame switch-offThe flame switch-off was detected after an abnormal delay. Vaillant uses F.62 as a diagnostic fault code across…F.70Vaillant · Gas boiler · United KingdomDevice Specific Number incorrect or missingThe Device Specific Number is missing, incorrect or does not match the coding resistor. Vaillant uses F.70 as…F.72Vaillant · Gas boiler · United KingdomInvalid flow and return sensor spreadThe relationship between the flow and return temperature-sensor readings is invalid. Vaillant uses F.72 as a diagnostic fault…F.75Vaillant · Gas boiler · United KingdomPressure change too low at pump startThe expected pressure change was too low when the heating pump started. Vaillant uses F.75 as a diagnostic…