2 port valve

[suggy]

why is the grey live and the brown switched live at a zone valve?

 

[Deleted member 9648]

There is micro switch inside the valve which closes when the valve opens,(connected to grey and orange) and is used to switch on boiler and pump.....The brown is used to open the valve.....a separate permanant live is connected to the grey and the orange is connected to the pump/boiler.

 

[silva.foxx]

S-Plan - hot water zonal valve; brown switched from cyl. stat

S-Plan - central heating zonal valve; brown switched from room stat

I'm sure there's variations in everyone's field wiring and these diagrams are purely for info.

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