Boiler Breakdown Fault Codes
Where to find them, What are they for and their limitations.
Search your fault code type make and model of your boiler and add the fault code without spaces; E.g. Vaillant Ecotec f22 (rather than f 22)
Faults codes are not definitive, they are trigger by specific sensors or differences between sensors for example if the flow temperature sensor is overly divergent from a return temperature sensor this would trigger a fault code. Faults codes are they indication of fault are a guidline for example a certain fault code might indicate accroding to manufactureres instructions that a fan has failed as the boilers princted circuot borad does not recieve information (a complete circuit) from an air pressure switch installed as a safety device to monitor the fan. However if the safety device itself were to fail the same fault code would appear. A professional gas engineer would never chnage a part based on a fault code but would use ithe fault code to aid investigation of faults.