Patent ID: 7424343

Claim:
A system for load control in an electrical power system, comprising: a thermostat configured to control a cooling system; a data interface device provided to said thermostat, said data interface device configured to receive commands, said data interface device addressable using an identification code, said data interface device comprising one or more sensors to measure one or more physical characteristics of operation of a refrigerant cycle in said cooling system and a processor configured to compute an operating efficiency of said refrigerant cycle of said cooling system at least in part using data from said one or more sensors, at least one of said sensors configured to measure a temperature of a refrigerant in said cooling system; and a remote monitoring system, said remote monitoring system configured to send a first command to said data interfaced device to adjust loading on said electrical power system, said system configured to use said data from said one or more sensors to diagnose an anomalous operating condition of said refrigerant cycle system, wherein said anomalous operating condition comprises a refrigerant undercharge.