Pilot lights, but not main burner

[AnonymousImport]

I have an intermittent problem where the pilot lights correctly but the main burner does not.

If I stop the demand for heat and water by advancing the programming unit to off for 1/2 hour or so it usually works properly

Could it be a malfunctioning multi-function controller ? (gas input controller)

It is a glow worm model combi.

Andy

 

[AnonymousImport]

Sounds a though you have a problem with the thermocouple that detectes the presence of the flame of the main burner. If no flame is detected then the main burner valve is shut down to prevent unburned gas accummulating. You can buy universal thermocouples or the specific one for the boiler BUT... as this is a safety device you should have a gas engineer install it (if you are UK based a CORGI installer). If an accident occurs due to incorrect fitting you can be held criminally responsible.

 

[AnonymousImport]

Firstly thanx for the reply

Listening to the various noises coming from the startup sequence I don't think the valve for the main burner is opening - the pilot light consistently lights everytime - looking at the valve (in-situ of course) it looks like its a 2 stage one.

Would too low a pressure / dirt in the gas supply exhibit a similar scenario ? (we recently had works done on the main road by Transco)

Naturally a CORGI engineer would fix a gas related problem - but I want to make sure thats the case first (or be reasonably sure it is) before calling one out