I have a Worcester/Bosch 240 combi boiler and it seems to be running all the time, when it does rest it is only for a short spell.
However it also trips out when we run the hot water so
i have to reset it.

Mr M Percival, December 2009

when you say running do you mean ignited? and are the controls,ie programmer and thermostat in the off position? if they are and the boiler is still firing then this shows either a fault in the controls or the PCB either way get a qualified engineer to call, the tripping out on hot water will be down to a dirty heat exchanger dirt comes from unclean heating systems

The plumber, December 2009