First suspect is secondary hex boiler side. Boiler going into lockout could also mean scaled up primary hex or a number of other faults.
BG is about the last one you want to get in as prices are sky high and skill depends entirely on who they send; could be top bloke or total numpty (more of the latter), but price is the same.
Best way of finding proper chap is to ask local friends, colleagues and neighbours until you find one who has had the same engineer repairing their boiler several times. Unfortunately, repairs are the only way to separate the men from the boys.
Promises, decades of experience (can't check that anyway) or being "a nice chap" mean less than nothing, and dito for installing or servicing.
BG is about the last one you want to get in as prices are sky high and skill depends entirely on who they send; could be top bloke or total numpty (more of the latter), but price is the same.
Best way of finding proper chap is to ask local friends, colleagues and neighbours until you find one who has had the same engineer repairing their boiler several times. Unfortunately, repairs are the only way to separate the men from the boys.
Promises, decades of experience (can't check that anyway) or being "a nice chap" mean less than nothing, and dito for installing or servicing.