Heating Issues - Combi (ufh and rads)

[Burkle]

Just a brief update on things again - since sunday and stripping the parts down again and putting everything back (old diverter and pins, new washers; old pump; new/refurbished heat exchanger) hot water has been fine still, no noise from boiler, and heating has worked perfect morning and evening every day except tuesday evening and wednesday morning (when the ufh had warmed up but not to the same extent, and radiators warmed for first few minutes only then nothing with boiler still on and water at temp). As above points, probably points to electrical / PCB issue, possibly still flow issue (although i cant see it being a blockage moving about unless its in the boiler as it would effect flow on both)... still no pattern to it! Waiting for boiler quotes.

I just dont like not knowing why something just doesnt work properly anymore!