Hi, I have a problem with my Worcester Bosch 240 Combi RSF - the pilot light is on, and there is demand for heating, but the main flame just doesn't start. Even if I turn the hot taps on, still no main flame. The red reset button hasn't popped up, and the pressure cold is at 1 (OK). And when there's demand, I can hear a sound (either the fan or the pump, don't know which) which goes off when the demand stops.

The strangest thing is that this morning, a couple of hours after the timer switched the heating on, it fired up - without me doing anything!

I'd appreciate any advice of things to try to see what the problem is!

Simon, February 2010

pilot light is lit but keeps sparking help?

paddy, December 2011

Had a similar fault. It turned out to dirt in the main gas valve. Workmen had renewed gas main in street and disturbed dirt which settled in gas valve, (Honewell) (Bottom right) When the boiler is off, the pilot should not be lit as it's electronic spark! With the pilot on, it tells the boiler not to light up! You can test this. If there is a tap on the Gas supply pipe. Turn if off till the pilot goes out. Then turn tap on and see if boiler lights up when calling for CH or HW. Hope it helps. I cured mine by turning off the gas. Remove plate on right side of valve, 6 screws, carefully remove to see one large rubber diaphram and one small rubber seal with spring. Remove and clean and give a good blow through were they sit. Re-assemble. If you are not confident and the earlier test worked, the get a qualified engineer to do the work! It will save pounds if you direct him to the fault.

John, April 2010

fan sticking? hard to say but thats a pretty common one with the older worcesters

z, February 2010