Vapor cycle system evaporator control

摘要

A refrigeration system which may be operated to control superheat at an inlet to a compressor (12) to produce a controlled superheat or to control a temperature of a fluid cooled by at least one evaporator (68) to provide the cooled fluid at a set temperature by controlling an opening of at least one expansion valve (62) in accordance with the invention includes a temperature control (206) which is activable to control the at least one expansion valve to cool the fluid to a set temperature in response to an enabling signal; a superheat control (208) which is activable to control the at least one expansion valve to control the superheat at the inlet of the compressor in response to an enabling signal; and a controller (204) responsive to the at least one logic operational state of the refrigeration system, for generating one of the enabling signals to activate one of the temperature control or the superheat control to control the at least one expansion valve to control superheat or provide cooled fluid at the set temperature.