You can create a tailored algorithm or you can use Hartman Loop technology. You can implement better temperature controls for the chilled water supply or the condenser water. Keep your eye on the long term and pick your weapon.
Retrieving every last bit of performance from the system while stopping short of the surge line is no small feat. Dig into sizing, tower selection, chilled water loads and stability, and condenser water management to leave no efficiency stone unturned.
Finding the holy grail of centrifugal chiller optimization for all operating conditions is hard, if not impossible. This article will talk about the requirements of most chiller systems and means of control for condenser optimization.