The Efficient Home Forum

So I have newish evohome with valves in most room. All works fine. We also have heat recovery and I need to be able to 'open' the valve to the water battery when heat is needed so as to lift the air supply temp. What do I need to buy and how do I set it up (assuming it can be done) so that the valve opens to allow water to circulate into the water battery when heating is needed. I assume I need a MT4-230-NC but beyond that, I don't know how to control that unit and how I add that control to the system.

Thanks in advance

Something that will control a Motorised Zone Valve would be preferable.

I don't quite understand what you are trying to do? Maybe give me a call tomorrow?