DouginMB, surely if the system is hydraulically correct, the primary problems you suggest would exist at all loads (at least up to half load, if you're talking about one chiller)? Maybe they do, basseng would need to tell us that. I agree that it's worth defining as much as possible how the...
Why have a check valve in the common piping - this is meant to be minimal resistance? Either the hydraulics is set up right or it isn't - to my mind, using check valves to try and correct bad hydraulics is similar to painting arrows on the side of the pipe (inside?) to tell the water which way...