Baxi 552 back boiler - pilot light goes out after B.G, servi

Hello!
My yearly service was last Wed 19th. A young man & his assessor did the job ( over 2 Hrs )
I hadn't had any problem with pilot light at all, up until then. The pilot light went out 1 1/2 day later. I called B.G. & they came out 2 days later, despite having no heat or hot water. He re-light pilot light & stayed a while to make sure it was o.k. The next time the pilot light went out was Thurs & now ( Sat ). I can't help thinking it's something B.G. has cause while servicing, as it worked perfectly o.k. prior to the service.
Shortly after the last service, we had to call B.G. back out for a noise while the boiler was in its cycle. The pressure had been set to high from the service. Could this pilot light fault, also have been caused by the servicing by B.G.?
Regards SD

There are only 2 things that can cause this problem, the first is the thermocoupling which should have been replaced when doing the service, and the second is the gas valve solenoid in which case you might as well replace the complete valve.

These item can go at any time

Faults occur and services are carried out. It is inevitable that somewhere these events will occur at roughly the same time, ie a coincidence.

Are you on the "all in the cost plan"? If so, they have no excuse. The obvious solution is to replace the thermocouple and injector, as it is a minimal cost. It could also be a dodgy gas valve, but it is more rare.

There may have been a loose connection on the tc to gas valve junction that has now been disturbed. He could have adjusted the gas rate to the pilot burner, so it is too small.

Is the flame burning nice, strong and bule or floppy and yellow?

I'd be suprised if he'd done anything wrong with his assesopr there too.