glowworm ultimate 70ff ignition problem

[Chris H]

After 15 years of new build installations, fault finding is is not something I delve into much if I can help it.
Looked at a Glowworm Ultimate 70ff with an ignition problem. Upon going to the property was told the boiler was coming on but no heating or hot water, so immediately thought of the pump. Pump working ok but noticed with use of magnet the cold feed was blocked possibly only partially who knows. So over to the boiler and to realise that it wasn't actually lighting, fan running - electrode sparking - but no lighting. Inlet on gas valve has gas 21mb solenoid energises but no gas to outlet. Before I fork out for a new gas valve, does anyone know of anything else it could be. I have read similar threads which have stated after a new gas valve there was still an ignition problem.
I'm not normally to far off with finding faults but it's just the thought of paying out for parts and it still not working. I'm too soft and will end up out of pocket.
Cheers, Chris.

 

[gasmarc]

If the voltage is going to the solenoid and its correct it cannot be anything else I am aware off. I suppose you could put your u gauge on it and isolate on the valve and see if it drops ,sorry stating the obvious, personally I never stop learning

 

[Chris H]

cheers Gasmarc, helpful as always.

 

[Billy Bob Bob]

i would agree with marc if your getting the right voltage at the valve its failed,i have had a similar fault on a micron that was a blocked injector but thats very,very rare

 

[gasmarc]

depending on which gas valve ,if you have two similar solenoids you can do a resistance test which will hopefully prove the pilot one is faulty and maybe can be replaced with out the expense of a whole new valve 😛arty:

 

[aggis]

Common problem with these boilers is the pilot not igniting. Take injector out & clean [3amp fuse wire is good, but go carefull if you use a pin] The injector has 2 holes in it. Better still replace it. Make sure ignition lead isn't damaged & fit into the soft grey seal that sandwiches & the pilot tube, between front cover & case. Note case has to be fitted to operate boiler.

 

[evogt]

Common problem with these boilers is the pilot not igniting. Take injector out & clean [3amp fuse wire is good, but go carefull if you use a pin] The injector has 2 holes in it. Better still replace it. Make sure ignition lead isn't damaged & fit into the soft grey seal that sandwiches & the pilot tube, between front cover & case. Note case has to be fitted to operate boiler.

There is ya answer, very common fault on these.