whats wrong with my boiler?

[dannyandjack]

the pilot light on my boiler is on, but when the hot water or heating is switched on it doesn't fire up.
Does anyone know what could be wrong. The boiler is only a few years old.

[dothawkes]

well, my best guess would be that you should contact the installer and ask for a full refund.

[KARL]

There are more than one possible causes. The two I would rate as most likely is that a zone valve has developed a fault (i.e. is not switching the boiler on) or else that the thermostat within the boiler is faulty (i.e. does not close when the temperature of the circulating fluid drops). Unless you are fairly good at DIY you might find it awkward to establish the answer to the former (yes or no) and although the latter is laughably simple to deal with and does not compromise or even involve any gas lines or such, it is apparently illegal for non-CORGI registered personnel to attempt it. But here is what you do: locate the thin copper tube which at one end has a bulbous shape and is fed into a cavity within the boiler vessel (containing the circulating fluid) and at the other end is connected to the area where the knob is (adjusting the maximum temperature it will go to - usually numbers from 1-6 or even 9). Switch of the electrical power to the entire system. Dismantle to get the required access and replace the tube and knob assembly with a new "boilerstat" available from any plumbers' merchant, often for well under �10. If the boiler still doesn't work, you haven't identified the problem.

[RAYMAN]

Hi,go too www.diyfaq.org.uk might find an answer there.