Ac refrigerant circuit

Abstract

A number of variations may include a refrigeration circuit which may include a compressor operably coupled to an evaporator. Additionally, a compressor may be operably coupled to the evaporator using the suction line. Moreover, the suction line may include a pressure sensor and a temperature sensor.

What is claimed is: 
     
         1 . A refrigeration circuit comprising:
 a condenser operably coupled to an evaporator;   a compressor operably coupled to the evaporator using a suction line, wherein the suction line includes a pressure sensor and a temperature sensor.   
     
     
         2 . The refrigeration circuit of  claim 1 , further comprising a controller constructed and arranged to reduce the compressor capacity or disable a clutch during a low charge condition. 
     
     
         3 . The refrigeration circuit of  claim 1 , wherein the controller includes an algorithm to determine whether the circuit is in a low charge condition. 
     
     
         4 . The refrigeration circuit of  claim 3 , wherein a temperature sensor is disposed in the discharge line. 
     
     
         5 . The refrigeration circuit of  claim 4 , wherein the temperature sensor is the only sensor disposed in the discharge line. 
     
     
         6 . The refrigeration circuit of  claim 1 , wherein temperature and pressure are measured directly in the suction line. 
     
     
         7 . The refrigeration circuit of  claim 1 , wherein the pressure sensor and the temperature sensor are a single combination sensor constructed and arranged to directly measure both pressure and temperature in the suction line. 
     
     
         8 . A system comprising:
 a condenser operably coupled to an evaporator via a liquid line and expansion valve;   a compressor operably coupled to the evaporator via a suction line, wherein a pressure sensor and a temperature sensor are disposed in the suction line.   
     
     
         9 . The system of  claim 8 , further comprising a controller. 
     
     
         10 . The system of  claim 8 , wherein the controller is constructed and arranged to use an algorithm to determine a torque of the compressor. 
     
     
         11 . The system of  claim 10 , wherein a temperature sensor is disposed in the discharge line. 
     
     
         12 . The system of  claim 8 , wherein a temperature sensor is the only sensor disposed in the discharge line. 
     
     
         13 . The system of  claim 8 , wherein temperature and pressure are measured directly in the suction line. 
     
     
         14 . The system of  claim 8 , wherein the pressure sensor and the temperature sensor are a single combination sensor constructed and arranged to directly measure both pressure and temperature. 
     
     
         15 . A method comprising:
 providing a refrigeration circuit comprising a condenser operably coupled to an evaporator via a liquid line and expansion valve and a compressor operably coupled to the evaporator via a suction line;   measuring both a pressure and temperature directly in the suction line.   
     
     
         16 . The method of  claim 15 , wherein a controller is constructed and arranged to control flow in the refrigeration circuit. 
     
     
         17 . The method of  claim 16 , further comprising determining a torque of the compressor using the pressure and temperature of the suction line. 
     
     
         18 . The method of  claim 15 , wherein the pressure sensor and the temperature sensor are a single combination sensor constructed and arranged to directly measure both pressure and temperature in the suction line. 
     
     
         19 . The method of  claim 15 , further comprising reducing the capacity or disabling a clutch when it is determined that the circuit is in a low charge mode. 
     
     
         20 . The method of  claim 15 , wherein the condenser and the evaporator are operably coupled by the liquid line and the expansion valve.