Main Burner Glowworm Boiler

[rbentley]

My central heating uses a wall mounted Glowworm Fuelsaver 30B Mk2. It's given years of sterling service but a fault has appeared. When the boiler thermostat calls for heat, the gas valve solenoid clicks and the main burner lights perfectly with the correct-sized flames. But within 1 second, the flames die right back producing 'soft' flames which barely cover the burners.

I measured the solenoid volts as 22.3VAC

I tried tapping the gas valve and this seemed to fix the problem, but a day later the fault was back.

Any thoughts please ... Richard

 

[theoldboiler]

most likely fault is the solenoid on the gas valve is gone
will need replacing might need to replace gas valve depends on make of gas valve

 

[rbentley]

Thanks for that.

I have removed the gas-valve.
It's a ROBERTSHAW UNITROL 7000 BER-S7AL (PN 446-501-547). The solenoid looks as if it might be renewable.
I've put some photos at http://gallery.bigos.org/Glowworm-Boiler-gas-valve Does it look familiar?
I would appreciate guidance on where to buy replacement valve or solenoid

Thanks again

Richard

 

[bripl]

buy a new gas valve

 

[DP]

It would seem you are an end user. As such you are unlikely to have tools or expertise to check system tightness following work carried out on the gas train. You are strongly advised to engage services of a person registered and qualified in such matters.