My Worcester 28si keeps locking out shortly after firing.
I have ruled out primary sensor, dhw sensor, fan air pressure switch, pump, gas valve, burner and blocked heat exchanger.
The flue is fine and so is the pressure vessel.
I'm thinking either overheat stat or flame sensor fault now.
Any experience of this anyone?
Cheers.
Steve.

Steve, May 2008

kleen the probes on the burner these sense the flame has ignited and hold the gas valve open

ryan, May 2008

flame rec is good possability

iain, May 2008