We may have found other answers which could help you.
Click here for Main Combi Water Pressure
How can my boiler be fixed i main Medway 55/54 ?
How can I reduce the pressure on my boiler?
My Main 30HE loses pressure over 24 hour period?
main combi 24he wont stay lit?
Main 24 Combie Boiler causing power trip of all power to home?
can I fit this myself or do I need to be gas safe engineer?