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Buderus GB142-24 Zone valves / relay box wiring
I am preparing to look at 4 zone valves and a grundflos variable spped circulator for that Buderus boiler. Anyone out there have opinions on (1 )which zone valves will give me the least trouble and (2) will be compatible with what relay box and the bolier (3) do we need end switches or no end switches on the ZV's (4) yes the DHW is built in control with the boiler.