Evening all. I have a query I'm hoping someone can help me with. I have just had an extension built and have wet underfloor heating and radiators in rest of house . There is only one pump live from the boiler . Problem I have is whichever source of Heating is selected both pumps come on . Anyone any idea how to wire this up So I can have either under floor heating or radiator pump on individually ?? I have 3 x 2 port zone valves . For underfloor , radiators and cylinder .