A method of determining suction pressure of a compressor suction valve in a vehicle air conditioning system

• Main Authors: Mike Rowland, Jim C Rollinson, Hugh Hamilton, Stephen Michael White, John Eric Rollinger
• Format: Patent
• Language: English
• Published: 27.01.2021
• Subjects: ARRANGEMENTS OR ADAPTATIONS OF HEATING, COOLING, VENTILATING,OR OTHER AIR-TREATING DEVICES SPECIALLY FOR PASSENGER OR GOODSSPACES OF VEHICLES; PERFORMING OPERATIONS; TRANSPORTING; VEHICLES IN GENERAL

An air conditioning system comprises an evaporator fan 710 and a compressor suction valve 71. A method of determining the suction pressure of the compressor suction valve comprises determining the speed of the evaporator fan and determining the suction pressure of the compressor suction valve based upon the speed of the evaporator fan. A vehicle air conditioning system having a compressor, compressor suction valve, evaporator having at least one evaporator coil 720 and an evaporator fan, and a controller is also claimed in which the system is configured to set the suction pressure of the compressor suction valve based on the speed of the evaporator fan. Determining the suction pressure ideally comprises determining the temperature of refrigerant in the evaporator based on the speed of the fan and calculating the suction pressure based upon the determined refrigerant temperature. The temperature of air entering the evaporator may be used to calculate the temperature of refrigerant in the evaporator. The current through the suction valve may be determined based upon the suction pressure.