Sometimes when the CH or HW calls for heat the fan comes on and just as the boiler fires it goes to lock-out.
Replaced circuit board, ingnitors, temp sensor and presure diff sensor.
One thing that also happens now and again is that there is a bang as if a valve is sticking. (Have replaced the 3-port but not the CH 2-port valve)
Could it be that if the CH valve is not operating correctly the boiler could go to lock-out
Regards
Apologies
Boiler: Saunier Duval SB30 - 10 years old
Replaced circuit board, ingnitors, temp sensor and presure diff sensor.
One thing that also happens now and again is that there is a bang as if a valve is sticking. (Have replaced the 3-port but not the CH 2-port valve)
Could it be that if the CH valve is not operating correctly the boiler could go to lock-out
Regards
Apologies
Boiler: Saunier Duval SB30 - 10 years old