While you wait for answers, we may have found some information which could help you.
Click here for Flow Return Boilerunable to light pilot on thorn m44/54b boiler?
apollo boiler banging noises ?
can I fix my internal flue hood on Thorn Olympic 15/60?
thorn back boiler housewarmer s?
Location of pilot light Thorn Housewarmer Super back boiler?
How do I light it?