Potterton Kingfisher MF PCB Problems?

[Markidows]

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




--
Markidows

[geoff]

In message <Markidow...@diybanter.com>, Markidows
<Markidow...@diybanter.com> writes

Get a man in who has a clue what he's doing, you obviously don't and you
might have left the gas valve in a dangerous state with your fiddling
about. Oh yes - diybanter, what did I expect

A common fault with the kingfisher is that the gas valve goes short
circuit and blows a resistor in the module. If you put another pcb in
without checking the gas valve circuit resistance, then you will almost
certainly have taken out the pcb

or, you might have bought the pcb from Allspares, in which case, who
knows if it is a working pcb or not


--
geoff