While you wait for answers, we may have found some information which could help you.
Click here for Radiators Home Heating Glowworm
I have a 30cx glowwarm that is showing F4 as fault.I have no hot water?
My radiators not heating up?
GS 24i junior boiler timer broken?
fitting thermostat?
How to fix glow worm 18 hxi ?
Glow worm flexicom 30cx auto air vent - how do I replace?