Yeah your right, I only got a service a few months ago through a friend of mine that said he was experienced but he didn't do much, he was only there a half an hour, which i know couldnt have been a proper service, when I cleaned the burner i turned off all power to the house and there wasn't a problem, I went and got the solenoid coil and oil nozzle this morning, and it's still the same sound. The fan comes on for about 10-15 secs then makes a small gurgling sound for 3 secs then goes to lock out and then red button stays lit, I pulled out the photoresistance and tried to start it but this time the fan stayed on with no gurgling sound so I reckon it's just a faulty photoresistance that's preventing it from starting up. My friend is away for the next 2 weeks and I was going to wait for him to come back, to get in contact with that other service guy that previously done the boiler, I know your saying it could cost much more buying parts for it when I can get a serviceman in, but I just wanted to try sort it myself if I could ye know, do you have any ideas, cheers. . .