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

Hi all,

just wanted to report back what the problem was with this. The 3-port
motorised valve was sticking slightly after the summer off period and
seems to be fine now. Boiler is fine.

Jonathan