Hi, I'm new to this site, found it while searching for answers to my boiler problem, I've got a Potterton Netaheat 16-22mk2F boiler. It stopped working about a month ago and is covered by a service contract with British gas. After inspection by several engineers they informed me that the PCB was u/s and as it was obsolete they couldnt help me, so they posted the usual notices and shut it down. I have now managed to replace the PCB and also the relay which was knackered (though nobody noticed) and I am still no further forward. When you turn the boiler on nothing at all happens, there is no clicking from the relay and certainly no fan running. I have now had another two gas fitters look at it and neither could decide what was wrong with it. I am convinced the fault lies with the thermostat on/off switch. Any help would be greatly appreciated.