While you wait for answers, we may have found some information which could help you.
Click here for Central System Maintenance
Worcester 30 Cadillac combi boiler won’t fire up and the EA?
Remove cover off gas boiler?
Oil fired boiler thermostat?
One radiator in a bedroom is always cold?
How to fix my fireplace?
Greenstar 24Ri boiler, fast flashing - can I reset?