by corresponding variable speed drive vsd 1230 a corresponds to condenser pump 1206 a vsd 1231 a corresponds to condenser pump 1207 a and the said drives 1230 a 1231 a are commanded by a controller 1233 a the controller 1233 a monitors the present loading on the water system either by measuring the present power consumption of operating chiller 39 s 1203 a compressor using a power sensor or the speed of the operating chiller 39 s 1203 a compressor using a tachometer or measuring discharged chilled water temperature and the discharged condenser water temperature by temperature sensor located in appropriate location in the water circuit or some other means from which loading can be inferred based on these loading signals 1234 a an algorithm calculates the optimum power loading subject to limits for the pumps and sends an output signal 1235 a to the respective two variable speed drives 1230 a 1231 a operating the two corresponding condenser pumps 1206 a 1207 a such that the two corresponding condenser pumps 1206 a 1207 a were incorporated to run at equal reduced speed or almost equal reduced speed or similar reduced speed simultaneously and operate at the optimum power percentage or ratio subject to limits of maximum power draw based on the present percentage or ratio of maximum loading subject to limits on the condenser water circuit 1200 a as described above in the event of variable speed drive s or condenser water pump s failure an integral bypass switch 1236 a not shown.