Vokera compact HE boiler. The system was in workable order last thursday, I was away for the weekend till Monday. On my return there is no hot water or heating. The green light is flashing on every 0.5 second. My manual shows this 'a temporary fault - wait'. The pressure bar was showing at 0.4. I have re-pressured the system & bar now showing between 1 & 1.5. There is still no hot water etc... Should i give it 24 hours or is there something else I can do?