potterton boiler ignition

[clipper74]

All,

I have a potterton suprima 40 boiler that is starting to suffer problems igniting. I'm well aware of the PCB problems that these boilers have, but it has a new and working PCB fitted.

The ignition seems poor just now. There is a windows to see whats happening inside and the blue spark coming from the ignition electrode(?) seems very weak. I remember after it's last service how strong it looked but now it is hardly sparking and is almost too weak to see. The ignition electrode has been cleaned and on the advice of some potterton forums it has been bent ever so slightly towards the burner to reduce the gap.

I'm not sure what I need to replace though if I'm to fix the problem. Would it be the cable from the PCB or the electrode itself? It is a white cylinder with an L shaped metal arm and seems to act as a spark plug. Can these be replaced? How do you do it and what are they actually called? The bolier is 10 years old and has not had any parts replaced bar the PCB.

Many thanks.

Steve

[geoff]

In message , [e-mail] writes

Do you have a red HT lead ?

yes - the "cable" from the pcb to the electrode

are there 13 sparks, then it stops, sequences again twice and then goes into lockout ?

Red HT leads are prone to not flame sensing - it would be a good idea to change it anyway for the few quid it costs

[John Stumbles]

did you catch the recent thread in which geoff (aka raden) pointed out that there are suprimas with dodgy HT leads? Apparently if they're red they're carbon fibre rather than copper, and crap.

[geoff]

Which I have repeated in this thread

[clipper74]

Thanks a lot. A serch didnt show up your previous thread, but then I didn't really know the names of the components and didn't know what to search for.

Many thanks. I'll replace the HT lead. It is looking a bit frayed at the spark end, I was surprised it was not copper but some sort of fibre.

Cheers,

Steve

[clipper74]

I've phoned around my local suppliers and nobody seems to have anything in stock. Does anyone know of any online shops that sell HT leads suitable for the Suprima 40? Or even the part number that I might search google?

Thanks, Steve.

[geoff]

In message , [e-mail] writes

As long as it has a 1/4" spade receptacle on one end, a 1/8" on the other and is about 18" long that should be OK

Most CH merchants should sell such a beast

[clipper74]

for any ones info;

part number 8407753 electrode lead.

I ordered a new HT online and a new electrode just in case. Now if only I can get the electrode screw un-done!

Steve