Suprima 50 cut-out

[pmc666]

Hi,

this is probably dead easy, but I'm stumped. I've just replaced the PCB on my Suprima 50 (with a new 5111603) with the intermittent failure problem (as reported on this board ad-infinitum). I now get this behaviour:

Lights come on - green/orange flashing
Igniter clicks the boiler into life (definitely flames)
about 1 second later the thing cuts out.

Repeat another 4 times and then I get the red led flashing once per second (lockout). Resetting just repeats this behaviour.

Any ideas?

thanks

 

[meldrew's_mate]

Have you replaced the overheat cut-out? Its much cheaper than the PCB.
Check the Air pressure switch and impulse lines too.

 

[ollski]

Also worth checking the pump is wired into the boiler correctly although it would normally take more than a second to fault.

 

[mmalone]

Hi,

this is probably dead easy, but I'm stumped. I've just replaced the PCB on my Suprima 50 (with a new 5111603) with the intermittent failure problem (as reported on this board ad-infinitum). I now get this behaviour:

Lights come on - green/orange flashing
Igniter clicks the boiler into life (definitely flames)
about 1 second later the thing cuts out.

Repeat another 4 times and then I get the red led flashing once per second (lockout). Resetting just repeats this behaviour.

Any ideas?

thanks

zone valves operating ok ?? pump operating ok ?? thermister ?? overheat stat ?? check all these and there aint much left

 

[ollski]

There's some sort of diagnostic mode on this pcb aswell, check the manual and I think there is a sticker on the side of the new board aswell.

 

[pmc666]

There's some sort of diagnostic mode on this pcb aswell, check the manual and I think there is a sticker on the side of the new board aswell.

I solved it. Took the whole think apart put the old board back on - everything worked (except that I knew it was going to stop working after a while). So packed the other board away and waited to see if any sage advice came from the board, and tested all the components with a multimeter (everything seemed sane - switches switched, and other things showed resistance as you'd expect). This morning I was just about to pack it up and send it back saying "I think your board's faulty mate - please send me a new one" when I noticed that the igniter cable was not attached properly. D'oh!

There is a little gap above the connector on the PCB (between it and the plastic case) that the wire connector fits into really snuggly, just like it was really attached. Oddly, even when not attached, it still manages to light the flame, but obviously it can't detect the flame like this.

Thanks to allski, mmalone, and meldrew's mate for the wise words.

Cheers

Paul