That's what i thought Nige,
Weird tho as last night started it again it coughed for a sec or two then ran fine. left it running for 25mins while do other jobs it was fine. then it swicthed itself off didnt cough/spullter just as if some one flicked the key back. i walked round flicked it back on and it started/ran spot on for a further 10-15mins till i switched it off. now i know its out to wind me up!!