I am having trouble with my gloworm65-80, The pilotl ight has gone out.So i have been lighting,then once it is lite,i press down the ff pilot button to release i hold it for 30 seconds or more,at this stage everything looks fine ,but once i release it it goes out .Can any1 tell me what the problem is, i am now awaiting british gas,i am in their homecare plan ,but my gloworm 65-80 is 25 years old ,i keep getting told that their cant get parts, i just dont want them to conn me into a new sytem. i need advise asap