At site, system has 1 80 ton RTAA with 12 CWAHU and 2 liebert fcu,
I have been bleeding off air at the highest point in the system, prob 15 cubic feet of air, the coil temp went from 78 to 52, the next day same issue, So i decided to add auto air vents, well no more problems there but now also on the highest floor, another mechanical room is AIR LOCKING another cwahu,
so I will BANDAID this as well,

Question, how does air enter the system,

1, suction at the pump due to bad gaskets,
2, incoming auto refill on the cw system due to maybe a possiable leak somewhere, incoming city water having air, which goes to the air seprator first,
3, air seprator is bad {15 years old} ( what I am thinking) which is at ground level.. there was no air vents at the highest point until i added,

NOW THE REAL QUESTION,.

1. There are 2 pumps for the building, estimated 200 GPM per pump,
ne 80 chiller, one pump for barrel, two pumps for building, redundant.

2. now, only one building pump is needed ,

3. the building is getting new BAS and the installer turned on both pumps for the building, and i am thinking that one building pump is pulling water from the other pump (starving each other) .,

4 QUESTION.,
IF THERE ARE TWO PUMPS AT 200 GPM EACH, IF BOTH PUMPS ARE RUNNING SHOULDNT THIS EQUAL 400 GPM? I AM THINKING SO,

5, with one pump running BAS shows estimated 140 GPM supply , with both pumps running BAS show 190 supply GPM.

WHAT YOU PROS THINK?
THX brosphers= brothers=fellow service thermodynamic engineers!

BTW , i was going to have the big dogs come out and give their opinion,.