We may have found other answers which could help you.
Click here for Tap Main MedwayMain Combo Eco Boiler Error Code E133?
My Main 30HE loses pressure over 24 hour period?
Why does my boiler keep switching on and off?
Fault on fan or flue?
Can I get the instructions to add more water to boiler pressure is just bel?
How can I fix my Main Combi 30HE boiler?