In this paper, an optimization approach is proposed for the control center in the two way load management system to coordinate the direct control of a large number of central chillers. The optimization approach is called the "real time two way direct load control algorithm" (RTDLCA), which finds the suitable central air conditioning customers to control by integer programming. The RTDLCA calculates the follow up load to shed based on the monitored air conditioning load and minimizes the difference between the load planned to be shed and the real load has been shed. The time lagging of load variations of every chiller under control as well as load profiles being sent back via broad band network is considered and is signified in RTDLCA.