I can not get C/Heating on VCW GB 242 EH Vaillant Combi Boiler ?
I have just renewed the Divertor valve on my combi I have hot water while switch is in Summer mode, but when I switch to winter mode I do not get heating nor H/water I have checked the wiring and noted I have not got power between 3-4 on terminal block.I know this should be live when demand is asks for would it be PCB or anyother fault.