Pilot light keeps going out with heating on...any ideas?

[gingman]

We have a Glow-worm Swift Flow 75/80 boiler. The pilot light ignites and stays on - heats the water fine...but when we flick it onto the heating it will stay on for a while (30 minutes last night) and then the pilot light goes out. It re-ignites ok but just won't stay on whilst the heating is running.

When we flick it onto heating all the radiators heat up etc but the pilot light just won't stay on.

We've recently had a service and all ok, and we've replaced the thermocouple as our gas man thought it could be that but still the same problem!!

Also, we've noticed that when the heating is flicked on the pressure very slowly increases. Last night for example it started at 1.3 and ended up getting to 2 in 30 minutes and then the pilot light went out.

Does anyone have any ideas as to what the problem could be?

 

[Agile]

Matters relating to the pilot light are gas and safety aspects and need a competent CORGI.

There seem to be several problems with your boiler.

The expansion vessel seems to need checking and its probable that the pilot goes out because its overheating.

Tony