摘要 |
Apparatus for providing integrated control of a space cooling system (20) is disclosed. The apparatus receives inputs from a plurality of temperature sensors, including a temperature sensor for mesuring evaporator superheat (29, 28), space temperature (31) and compressor discharge temperature (30). The control apparatus incrementally adjusts the position of the cooling system expansion valve (24) to regulate evaporator superheat and compressor discharge temperature and cycles the outdoor condenser fan (27) on and off to raise condenser pressure in response to a low condenser pressure condition. In one embodiment, the cooling system includes a plurality of evaporators (21) and a corresponding plurality of controllers (25) electrically interconnected in a series loop for controlling the expansion valves (24) and defrost heaters (34) associated with the respective evaporators (21). One of the controllers functions as a master controller and receives inputs from the space temperature sensor (31) and the compressor discharge temperature sensor (30) as well as from the temperature sensors (28, 33, 29) associated with the corresponding evaporator (21).
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