That is exactly what it was, thank you Ian the handle turned around the valve instead of turning it off. Thanks to everyone who offered suggestions. Much appreciated but Ian gets the biscuit.
Sorry, I have a glowworm 30cx fitted 2 years ago serviced annually. I have central heating but no water from the hot tap, either hot or cold. No warning lights, I figure an automatic valve has shut off. I tried resetting it. Pressure is 1.4 bar.