Yes it is an S system two valves
I can say that I have checked with a volt metre and can see the HW demand go off and the valve wind back, the pump also stops
No but can do now
Power is constant and valve just closed
Am I correct in assuming the orang wires are switch returns?
Andrew thank you, ***** ***** the motor a year ago, looks like it has gone intermittent again its a honeywell
thank you for your time Andrew cheers