heating is on but no hot water?
 
                A LITTLE MORE DETAIL - SORRY !!
i have ravenheat RSF 84 E  - HEATING OPERATES FINE  ! WHEN HEATING IS ON AND I TURN HOT WATER TAPS ON I BRIEFLY GET HOT WATER THEN MAIN BURNER CUTS-OUT ,  WATER IS LUKE WARM  FOR 2 MINS ( APPROX ),THEN MAIN BURNER FIRES UP AGAIN THEN SHUTS OFF AGAIN.  WHEN HEATING IS TURNED OFF,  I OPEN HOT WATER TAPS , I RECEIVE HOT WATER ( TEMPORARILY) THEN BURNER CUTS -OUT AGAIN !  
P.S I HAVE NO INTENTION OF TRYING TO FIX THE FAULT PERSONALLY - I JUST WANT AN UNDERSTANDING OF THE PROBLEM  SO AS WHEN AN ENGINEER ARRIVES WITH SLEDGEHAMMER AND STARTS SPEAKING SPANISH ,QUOTES ME £200 THEN PROCEEDS TO HIKE THE BILL UP TO £350 (LIKE THE LAST GUY)  ... JUST DONT LIKE GETTING HABITUALLY  SPANKED BY A SWEATY-PLUMBER WITH A SLIPPERY SMILE- NOTHING PERSONAL, IM JUST A HUMBLE JOINER WANTING A FAIR SERVICE :)     THANKS
            
             rob
            
 April 2008