R404a water cooled condensing unit with 8oC cooling water

[Gary]

Where there is refrigerant in both liquid and vapor form (condenser, evaporator), the temperature and pressure coincide.

If the condensing temperature is low, then the condensing pressure is also low. If the condensing pressure is too low then there isn't enough pressure in the condenser to push the liquid refrigerant through the TXV and into the evaporator.

The choices are to raise the temperature of the water or to reduce the flow of water through the condenser. Either of these strategies will raise the condensing temperature/pressure.

The purpose of the water regulating valve is to control the water flow in order to regulate the condensing temperature/pressure.