While you wait for answers, we may have found some information which could help you.
Click here for Overheat Ravenheat Boilerravenheat csi 85 b (t) hot water no central heating?
Central heating but no hot water?
Ravenheat CSI 85 Red Light?
What is wrong with my ravenheat white star combination boiler,?
Faulty Ravenheat condensing boiler?
Faulty Worscester 35 CDi loosing pressure?