glowworm 30ci has no hot water

[Mr Chibs]

Wonder if you bright sparks could help me please.

I've a old glowworm 30ci, which has been fault free. Today there is no hot water.
The boiler fires-up for heating, but won't fire-up when water is needed.

Not being lazy, I've read a few links so far and I'm a bit stumped.

Flow sensor (which I suspected), was clean and impeller spins easily (could this still be faulty?)
Water inlet filter clean.
PCB connections appear tight and no overheating marks on board.

There are no fault codes on display.

What would be next to look at?


TIA

 

[ianmcd]

has any plumbing work been carried out in your house recently ?

 

[Mr Chibs]

No nothing.

I read diverter valve then possibly heat exchanger are next in line, but these are a bigger undertaking, for me anyway.

 

[GuessMan]

If it’s a grey flow sensor i’d Place my money on that.

 

[AGAS]

If it’s a grey flow sensor i’d Place my money on that.

+1 change it for the new black one and also change the pink pressure sensor while you doing it as it would save a load of future problems

 

[Mr Chibs]

Cheers guys, its currently the grey one, will get a new black one ordered and report back.

 

[Mr Chibs]

Thanks all.

It was the grey flow sensor, it had a hairline crack inside, and had shorted out the chip on the tiny PCB.
Replaced with the black version, all is working correctly now.