Warm radiators when hot water on!

OK checked valve wiring and all seems fine.

Its opening the valve (vertical) when hot water is turned on an horizontal when the heating is turned on, is this correct?

The water comes in from the pump into the `t` with the top pipe goin into the hot water tank and the bottom pipe going to the radiators.

But obviously both ends are getting hot when the hot water is turned o hence the radiators getting warm

-- rosso warrior

Is this a new problem, or has it always done it? If the latter, the return pipework could be connected incorrectly, permitting reverse circulation round part of the heating circuit.