"I would advise to remove the VR40 and wire the single system pump as shown in the example diagram below with a permanent 230V supply to the grey wires and use the oranges from all zone valves wired to the pump live."
That is the normal S plan configuration, there is a permanent live to one side of the zone valve end switches and all the wires (switched live) from the other end(s) are marshalled together to provide a a run signal to the boiler which now normally controls the boiler circ pump, so if any one, or all, zone valves are open then the boiler has a run signal and when all zone vales are shut then no run signal, I suppose with all their fancy control systems now, they don't use the end switches now but employ some virtual means of determining this hence all these status alerts or whatever.
It's a bit surprising that there is no contact on the boiler from the circ pump run signal, there must be some means of picking up this and wiring it via a external relay (if required) to run the external pump, I think this was suggested previously, above. Also, this implies that the (a) zone valve is kept open for the duration of any pump overrun, oh no, the pump won't run unless a zone valve is open!.
That is the normal S plan configuration, there is a permanent live to one side of the zone valve end switches and all the wires (switched live) from the other end(s) are marshalled together to provide a a run signal to the boiler which now normally controls the boiler circ pump, so if any one, or all, zone valves are open then the boiler has a run signal and when all zone vales are shut then no run signal, I suppose with all their fancy control systems now, they don't use the end switches now but employ some virtual means of determining this hence all these status alerts or whatever.
It's a bit surprising that there is no contact on the boiler from the circ pump run signal, there must be some means of picking up this and wiring it via a external relay (if required) to run the external pump, I think this was suggested previously, above. Also, this implies that the (a) zone valve is kept open for the duration of any pump overrun, oh no, the pump won't run unless a zone valve is open!.
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