My boiler seems to have developed an intermittent start problem. It's been fine for 4 years with a new PCB fitted. All ok on DHW. When I switch on the CH and the room thermostat calls for heat there is no "click" in the boiler as there used to be and the boiler just sits doing nothing. What's happned to the "click" ?? Last night I eventually got it started and once it started it was fine and the thermostat works correctly but 95% of the time it won't start and the click is missing as the main "trigger". Help please.
Thanks very much.
Jonathan