Worcester 240 rsf - pilot ignite but not main burner

[beesley121]

Hi guys,

got or a worcester 240 RSF not giving hw or heating on demand. When demand is put to boiler, pilot light ignites, spark electrode continues to spark even though the pilot is lit but the man burner will not ignite.
Put gauge on gas valve and Gas valve not opening.

Gas valve has has been replaced as British gas said gas valve had failed so customer ordered part and another engineer fitted it to no avail. I'm thinking pcb but I believe these boilers have a separate sequence pcb. Anyone had the same issue with this boiler? How would I know which pcb has failed?

Thanks in advance

 

[Deleted member 32524]

sequence board is the one on your left with 3 plugs running down left and 2 on bottom.

 

[Deleted member 32524]

Test the top blue, brown n grey wires on gv. i think.

 

[buckley plumb]

had one it was the board but check flame sensing probe and wires 1st

 

[arran197]

I'd check the electrode, leads and earth. Make sure the pilot burner is clean and the flame is the correct length. Worcester are usually quite good on these cause they're old and most of the faults have been experienced before.

 

[southcoastboile]

Had the same thing with a board on this boiler but as above could be flame rectification issue

 

[bigcheese]

I had one earlier today which wouldn't light ever since it was serviced. The flame sensing lead had been damaged. If not that and the electrode itself isn't damaged, then I would go for the ignition board.

 

[beesley121]

Sequence board was the problem, all working now