Hi,
I have a Potterton Kingfisher Mf boiler that supplies my gas CH and found that when I attempted to start, the main burner would not ignite.
Fan comes on, set delay takes place then ignition sparking commences, pilot ignites, then nothing from burner. Unit ran for 2 hours without burner ignition.
After gentle taps and wire wiggling, my plumber friend and I have stripped gas valve and pilot light assembly, replaced HT/Sensor lead and performed continuity checks for earth, both internally and to ground. No success.
Following the installation manual fault finder, the voltage O/P from PCB is approx 5Vdc - not accurate but certainly not 175 Vdc minimum recommended in manual. The same is measured at the valve, and body is slightly magnetic. 200 Vdc were measured at pilot valve terminals, and strong mag field in valve body. Manual suggests PCB is problem.
Plumber also diagnosed PCB with 95% confidence and I ordered a refurbished item. After fitting, problem remains. Am unable to get a reply from supplier yet.........
Can two PCB's be duff, or are we missing something? Would appreciate any advice, divorce imminent if not fixed soon!!!!!
Thanks
Mark