@smali1: Is there any reason you'd want to stick with a VPF system, if you are concerned about energy efficiency or low delta T mitigation those can be addressed with a variable primary-secondary system. basically with all the advantages of the VPF along with the reliable supply of a secondary...
From my understanding, the DPT (differential pressure transmitter) can be located at the furthest component of the critical loop (i.e loop with the highest differential pressure requirement for the necessary flow)to operate the entire system, it doesn't matter if its 3 buildings or 1 building...
