(NOW FIXED) Potterton Promax 15/24 HE - ignition lock out

[424BB]

Hi,

Anyway, it appears I have ignition lock out.

Boiler tries to ignite, fan starts, sounds of relays clicking away (sometimes a clunk), fan slows and stops....boiler attempts to ignite again as previously... fan starts, clicking and sometimes clunking...slows and stops.

This happens about six times before it gives up trying and I have to switch it on and off again for the whole process to re-start.

Occasionally it will ignite, this last for several seconds before the flames go out and the above process restarts.

It actually managed to force itself to stay ignited for around half an hour today before going and then not be able to start again.

Sometimes the clcking and clunking continues and doesn't stop until I switch it off and start again?!?

I am not a boiler engineer (I'm sure you guessed that), but I am an experienced engineer in other fields and am happy to try any suggested fixes to do with the electronics (not the gas obviously).

I have the cover and the air box door panel off and am hoping someone can offer some advice on things to check.

I also have the service manual in front of me.

Any help appreciated.

 

[424BB]

FIXED!

Opened it all up and saw there was sparking coming from the back of the ignition board.
Took it out and noticed the neutral point where the connector plugged in had a dry joint (as did a couple of others).
Re-flowed and working perfectly...nice to have some warmth back.