Patent ID: 7874166

Claim:
An apparatus comprising: a compressor for compressing refrigerant, said compressor driven by a power source installed in a vehicle; a condenser for receiving compressed refrigerant from the compressor; an expansion device for expanding refrigerant from the condenser; a heat exchanger for receiving refrigerant from said expansion device and for exchanging heat between said refrigerant and a liquid; a supply for supplying liquid to said heat exchanger for exchanging heat with said refrigerant; a reservoir for receiving liquid from said heat exchanger; a return path for returning liquid from said reservoir to said heat exchanger for heat exchange with said refrigerant; a pump coupled between an outlet of said reservoir and an inlet of said heat exchanger; and a controller for controlling said pump; said supply having an outlet coupled between said outlet of said reservoir and said pump; wherein said controller is adapted to control said pump based on one or more of (i) a parameter indicative of temperature of said liquid, (ii) a parameter indicative of the temperature of said liquid in said reservoir, (iii) a parameter indicative of the pressure of said liquid, (iv) the state of a switch for supplying power to said pump, (v) an indication of whether a dispensing valve is open or closed, (vi) the present time and (vii) a time period that the pump has been active or inactive.