I have a new heating system with 6 zones using motorised valves for: UFH, 4x rad zones and HW. But when only UFH in kitchen on, the heat still transfers thru rad circuit and goes straight up to top of house. Thought the MV's when closed would have stopped the water getting hot, beyond the closed valve. It's not even as if it's being recycled as pump obviously not flowing the water. Anything I can do about it???
