Vaillant Boiler Error Codes & Problems

F.28 Vaillant Boiler F.28 means the boiler attempted ignition but failed during startup. The most … F.29 Vaillant Boiler F.29 means the burner lit but the flame was lost during operation. Common causes … F.75 Vaillant Boiler F.75 means low system pressure or water flow detected by the pump and pressure …