protherm f1 fault

[panny300]

i had a problem with pressure dropping to zero,and was grateful for the advice on here that the expansion vessel had failed,which it had done so was replaced.
hot water works okay,but when heating has been on, F1 appears on the control panel.the manual says it is either.overheating or no flame detected.
on the front is a reset switch.
if i press this the boiler restarts and heating startsup.so i assume it is a overheat problem
any ideas on what the problem is,and how to check.
also the pressure still drops 1/2 a bar when cold.

 

[Agile]

To overheat it needs to be on for 20-30 sec minimum.

Much more likely to be a flame failure. Either gas valve sticking or min/max or ignition settings incorrect. That needs a competent CORGI.

Tony

 

[panny300]

thanks tony,i have not been home to reply,
the f1 fault is intermittent,the central heating can be on for a couple of hours and go off with the timer and no problems, the next time it comes on with the timer for a couple of hours the f1 fault shows.it seems to happen at the end of the timer period?

 

[Agile]

Even more likely to be gas valve min/max settings.

Needs a competent CORGi to test and reset.

Could also be PCB although less likely now you have added that bit of info.

Tony