Vokera Compact 28 - No Central Heating

[Probs]

Hi All,

I was hoping someone could help. We are having problems with a Vokera Compact 28 boiler where it refuses to heat up the central heating. Hot water warms up perfectly however no amount of convincing on our part makes it warm the heating which is handy this time of year.

I've noticed that if the DHW/CH switch is DHW the green light flashes every couple of seconds as normal. However when you switch it across to CH the light flashes constantly indicated a "Temporary fault"

We have checked the pressure, rest the system and checked all connection etc but to no avail. Does anyone have anything else I can try before I order a new PCB?

My logic behind the PCB side of things is that for the DHW to fire up and run I am assuming a majority of the mechanical components are working. Hence me thinking its the PCB.

Any help you guys might be able to offer would be great.

Thanks guys,

-Jamie