how to tell if motorised valve needs replacing?

If you have 2 two port valves turn the stat to full, park yourself by the valve that is for the heating then get someone to turn on heating after a short while you might hear a click and the boiler should fire up.depending on type of valve you may be able to see it operating then get the other person to turn stat down to zero, valve should close immediately.If its a 3 port valve you would need to access the connection box and disconnect the orange wire

toptrish
December 2013