While you wait for answers, we may have found some information which could help you.
Success
Message
Vaillant F22 fault?
Fan tries to run every 15 seconds then stops immediately?
Worcester boiler dripping water?
Siemens RDJ10RF thermostat problem?
Boiler cycle?
Worcester Bosch 532/i Combi Boiler?
Remove boiler cover?
How to fix my fireplace?
Remove cover off gas boiler?
Vaillant ecotec 831 plus?
British Gas 532/i Gas Combi Boiler?
How do I work my Storad storage heater?