Need help with S plan with a 3rd zone for under floor heating!

[i=p/u]

All oranges , greys , blues, green and yellows together, brown and black for each zone switching

 

[feebs73]

Ok will give that a go ta

 

[helloeddy]

hi,

I am just about to install a 2 zone s plan plus, one for rad's and one for UFH, both with separate stat/programmers, I have a vaillant ecotec plus 837 combi boiler, and have bought two NC honeywell port valve's, on the wiring do I wire the UFH pump to the call from the stat (brown) before the zone value so I don't get feedback from the rad's stat running the UFH pump?

also what do you recommend regarding pump overrun on the main boiler? I don't think it has the facility to have a direct input, so would need an external relay? and also for it to also hold the rad's port value open for the time also.

Cheers

 

[gnuuser]

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