Worcester 350 problem

[mikeyc]

Hi chaps, just been to a Worcester 350, fires up ok from first time central heating demand. Once the boiler gets up to temp and starts to cycle it just continues to cycle with pump running but does not go through the motions of going to ignition again - no overheat or anything and no lockout as such. The customer then has to turn off the boiler at the programmer and then back on and the boiler fires up on the button until it gets up to temp and cycles again.

Called technical and was told by an unconvincing techy that he thinks the sequence PCB is to blame.

Anyone else had this or have any other ideas? any help greatly appreciated

 

[Paulplumb]

I have had to replace to sequence board in them too when advised by their tech guys . The boiler would only fire for a second before flaming out. Maybe yours is on the way out? Make sure you buy a bag of standoff pegs for the board as they are likely to disintegrate when you take the old board out.

 

[gassafe]

I had a similar fault on old Worcester floor standing, it was the gas valve solenoid?

 

[bewsh]

Thermistors ok?