Intermittent clicking noise and occasional sparking. Having seen the solder joints clearly with a magnifying glass the cracks were obvious on the sparking connector. Turned power off and resoldered then checked with circuit tester to ensure joints were sound.
When I reconnected all leads and powered on, only the pump could be heard at switch on. Tried the reset button just in case, but still no action.
you have not connected fan to pcb the two red wires are short and if you pull pcb down fully will not reach look oround pcb area and at top you will see the two red wire lead plug,plug in and hopefully......
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix home heating systems.