Boiler not starting

[FrederickDeLarge]

Due to the house radiators coming on when hot water only is required, I have just installed a new diverter valve. On firing up afterwards, the boiler then only operated for a few minutes (on hot water setting) before cutting out and dying. Nothing I can do will bring it back. There is a faulty PCB in place, as discussed on another thread, but this has always worked so far albeit requiring the fan to cycle many times before igniting. Has this PCB now totally failed? The boiler is a Potterton Netaheat Profile 60e. Honeywell controls.

 

[gasafengineer]

More likely air in system & boiler stat reached temp , does boiler stat 'click'?

 

[Jordon]

Did you drain the system to fit the new valve? Maybe air or it's not circulating around the system! Does when it comes on get hot then shut the stat done on the boiler? If not the above do not work on the unit get a rgi in as these boilers can kill if messed with by a diyer

 

[Jordon]

Beat me to it lol

 

[FrederickDeLarge]

Thank you for your prompt help - it does seem coincidental that this trouble has started only after a system drain down. Although the boiler fired up at first, I don't believe enough hot water reached the cylinder to activate the thermostat before it shut down. The cylinder remained cold throughout. Yes, it is likely that air could be in the system - would this cause the shutdown? What can I do about that? And regarding PCB replacement, I have no intention of tampering with the boiler myself! But I would be glad to return to the previous imperfect state of fan cycling many times to start up. At least it started up!

 

[picasso]

you may have tripped the overheat stat, the reset button is on the bottom of the boiler.

 

[FrederickDeLarge]

That's exactly what happened. Found the reset switch and all started up again. Clearly the boiler has overheated through air being in the system so removing this air must be the next move. Many thanks guys.