Boiler not switching on

[Cranky]

I have a Thorn M - gas fired boiler (20 years old?). When I tried to switch to heating this morning it did not work. The pilot light to the boiler is on, the pump is working and there is a 240V supply to the gas regulator (is this a solenoid?) block. I have metered out between live and neutral on the regulator plug and there is no continuity, I have also metered on the contacts that the plug leads to and again there is no continuity.

Have you any ideas please?

 

[chrishutt]

Sounds like the gas valve solenoid has failed. What is the resistance across the solenoid (regulator) terminals?

 

[Cranky]

The resistance across the regulator terminals is Mega Ohms i.e. open circuit! should it read a resistance?

 

[kevplumb]

methinks it's fell off it's perch this is a dead solenoid

 

[chrishutt]

Yes it should show some resistance - not sure of the figure off hand - the terminals connect to the ends of a coil, so there should be continuity. So the solenoid must be faulty.