And the answer was...the heating dial was turned down for the CH and this seemed to trigger the sensor on the pipe to cut out the gas. Yup the tenant was messing with the dials. Once they had been turned up to max the sensor didn't cut out the gas flow and all was well. I've now got a new gas boiler fixer man.
£30 for 1 1/2 hours work. Top bloke !!!!
