Patent ID: 8069684

Claim:
Refrigeration circuit ( 2 ) for circulating a refrigerant in a predetermined flow direction, comprising in the flow direction: a heat rejecting heat exchanger ( 4 ); an evaporator throttle valve ( 8 ); an evaporator ( 10 ); and a compressor ( 22 ), and the circuit further comprising: an internal heat exchanger ( 16 ) placed with its â€œcool sideâ€ between the evaporator ( 10 ) and the compressor ( 22 ); an inlet temperature sensor ( 24 ) located between the evaporator ( 10 ) and the internal heat exchanger ( 16 ); an outlet temperature sensor ( 26 ) located between the internal heat exchanger ( 16 ) and the compressor ( 22 ); and a control ( 28 ) for controlling the evaporator throttle valve ( 8 ) based on the inlet and outlet temperature sensor measurement, wherein the control is adapted for: controlling the evaporator throttle valve ( 8 ) based on an inlet temperature setpoint at the inlet temperature sensor ( 24 ); and shifting the inlet temperature setpoint based on the outlet temperature sensor measurement ( 26 ); and determining an allowable range for the outlet temperature sensor measurements so that the shifting of the inlet temperature setpoint is only performed when the outlet temperature measurements go beyond the allowable range.