While you wait for answers, we may have found some information which could help you.
Click here for Combi Help 30pressure dropping on openning the hot water in my ravenheat csi 85 aboiler?
ravenheat csi 85(t) 780 series red light flashing?
Faulty Worscester 35 CDi loosing pressure?
ravenheat csi 120 no hot water?
minimal hot water ?
how can i ignite the pilot light on a ravenheat boiler?