Hi everyone , first post so be patient, went on holidays for a few days, came back and the pilot light was out on the boiler (Baxi WM 281 RS model) tried to re-light it by holding the grey knob in on the right while pushing the igniter button on the left, pilot light comes on while holding in the grey button but when you release it the pilot light goes out. I was told it was a defective thermocouple so I just fitted one and it is still the same, keeps a light with the grey button in but goes out when I release it, any advice would be very much appreciated, all the best and kind regards.