Well I need help with the wiring for my wet heating (UFH ground floor and radiators first floor) and combination boiler together.
Your UFH wiring centre should provide a switched live and/or voltage free contacts to call for the boiler to fire up. ...
Not sure if you can split out one zone and use this to control the rads upstairs (?).

My plumber said to use an S- plan wiring system. Can anyone enlighten me?
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