I've recently moved house and have a Randall 30 60 boiler programmer. We had no issues until we changed the timer for when the heating/ water should come on - we changed this by moving the little dials. The timer is working but it doesn't seem to be clicking into the timed slots for when we want the heating to come on, we have to manually click it over the dial. Can anyone advise? The boiler was serviced before we moved in. Thanks a lot