Intermittent hot water problem on a Glowworm Hotwater Express 100

[Rick]

Hi, I have a Glowworm Hotwater Express 100 combi boiler which according to the label stuck to it was probably installed in 1993. The boiler has developed a problem where the boiler doesn't fire up when the hot water taps are opened. Occasionally, the boiler will work but now it seems that the problem has got worse. The boiler emits a series of clicking noises when the hot water tap is open and the boiler hasn't fired. My wife noticed that she can get the boiler to fire by hitting it! Obviously, this is not a long term solution and once that I fear may even damage the boiler further. I had a plumber in and his initial thoughts were that the diverter valve was sticking. Later, he said that after discussing it with colleagues, he's not so sure and he's not keen in replacing it only to find out that the problem is still present. Does anyone have and ideas what could be the problem with the boiler? Thanks. Rick

[Darran Ames]

I had a similar problem with my Glowworm combi (which must be 15+ yrs old) recently. There were a few dry joints on the pcb that I resoldered. It's behaved perfectly since (excluding the thermocouple that I had to replace today...)

[geoff]

In message , Rick writes

Either the diverter valve or the PCB

If the CH fitter isn't sufficiently competent to work out which it is, get someone in who can

Not sure offhand what the clicks are though, I'll probably realise later