While you wait for answers, we may have found some information which could help you.
Click here for Raven Heat BoilerFaulty Worscester 35 CDi loosing pressure?
ravenheat csi 85(t) 780 series red light flashing?
Central heating but no hot water?
minimal hot water ?
ravenheat csi 85 b (t) hot water no central heating?
What is wrong with my ravenheat white star combination boiler,?