Method to Mitigate Catastrophic Failure of HVACR Equipment Charged with A3 Refrigerants

Abstract

A heating, ventilation, air conditioning, and refrigeration (HVACR) system that is chargeable with a refrigerant in a closed refrigeration cycle includes an HVACR enclosure, a vent having a vent outlet fluidly coupled with the HVACR enclosure for discharging air from the HVACR enclosure, and a refrigerant retention device. The refrigerant retention device is positioned to contact air and escaped refrigerant that has been emitted from the closed refrigeration cycle prior to discharge of the air from the vent outlet, wherein the refrigerant retention device comprises a porous refrigerant retention material which passes air to the vent outlet and retains the escaped refrigerant. A sensor can be provided to detect the presence of refrigerant and a gas pump can be operated to pass the refrigerant through the refrigerant retention device. A method of operating an HVACR system is also disclosed.

We claim: 
     
         1 . A heating, ventilation, air conditioning, and refrigeration (HVACR) system chargeable with a refrigerant in a closed refrigeration cycle, the system comprising:
 an HVACR enclosure;   a vent outlet fluidly coupled with the HVACR enclosure for discharging air from the HVACR enclosure; and,   a refrigerant retention device positioned to contact air and escaped refrigerant that has been emitted from the closed refrigeration cycle prior to discharge of the air from the vent outlet, wherein the refrigerant retention device comprises a porous refrigerant retention material which passes air to the vent outlet and retains the escaped refrigerant.   
     
     
         2 . The HVACR system of  claim 1 , further comprising a gas pump operable to move air and escaped refrigerant from the HVACR enclosure through the vent outlet and a sensor for detecting the presence of the refrigerant in the HVACR enclosure, wherein the sensor upon detection of escaped refrigerant operates the gas pump to move the air and escaped refrigerant into contact with the refrigerant retention material, and the refrigerant retention material will retain the escaped refrigerant gas. 
     
     
         3 . The HVACR system of  claim 1 , wherein the vent comprises a valve. 
     
     
         4 . The HVACR system of  claim 2 , wherein the valve comprises a motor, and the motor is operable upon receipt of a signal from the sensor. 
     
     
         5 . The HVACR system of  claim 1 , further comprising a processor for operating the sensor and the gas pump. 
     
     
         6 . The HVACR system of  claim 1 , wherein the refrigerant retention material retains at least one refrigerant selected from the group of propane, butane, pentane, R32, R1234ze, R448A, R407F, and R1234yf. 
     
     
         7 . The HVACR system of  claim 1 , wherein the porous material comprises pores having a diameter of from 4° A to 5° A. 
     
     
         8 . The HVACR system of  claim 1 , wherein the refrigerant retention device is a cartridge, and the HVACR enclosure comprises structure for removably retaining the cartridge. 
     
     
         9 . The HVACR system of  claim 7 , wherein the HVACR enclosure comprises walls, and the cartridge is removably connectable to at least one of the walls, and the vent inlet is positioned in at least one of the walls to draw air and escaped refrigerant through the cartridge. 
     
     
         10 . The HVACR system of  claim 1 , wherein the vent comprises a vent tube, and the refrigerant retention material is provided in the vent tube. 
     
     
         11 . The HVACR system of  claim 10 , wherein the vent tube comprises a vent lid at a discharge end of the vent tube and a valve at an inlet end of the vent tube. 
     
     
         12 . The HVACR system of  claim 1 , wherein the refrigerant retention material comprises at least one selected from the group consisting of zeolites, activated alumina and activated carbon. 
     
     
         13 . The HVACR system of  claim 1 , wherein air discharged from the vent has a concentration of refrigerant below the critical combustion concentration for the refrigerant in air. 
     
     
         14 . The HVACR system of  claim 1 , wherein the gas pump comprises at least one selected from the group consisting of a vacuum pump and a blower fan. 
     
     
         15 . The HVACR system of  claim 1 , wherein the HVACR enclosure is part of a refrigerator and encloses the compressor and the condenser of the closed refrigeration cycle. 
     
     
         16 . The HVACR system of  claim 1  wherein the HVACR system comprises at least one selected from the group consisting of a refrigerator, a freezer, a combination refrigerator and freezer, a central air conditioner, a room air conditioner, a heat pump air conditioning and heating systems, a heat pump water heater, a walk-in freezer, a walk-in cooler, a cold/frozen food display case, an ice-cream machine, frozen food vending machines, cold beverage vending machines. 
     
     
         17 . A method for operating an HVACR system, comprising the steps of:
 providing an HVACR enclosure; a sensor for detecting the presence of the refrigerant in the HVACR enclosure; a vent having a vent outlet fluidly coupled with the HVACR enclosure for discharging air from the HVACR enclosure; a gas pump operable to move air and escaped refrigerant from the HVACR enclosure through the vent outlet; and a refrigerant retention device positioned to contact air and escaped refrigerant that has been emitted from the closed refrigeration cycle prior to discharge of the air from the vent outlet, wherein the refrigerant retention device comprises a porous refrigerant retention material which passes air to the vent outlet and retains the escaped refrigerant;   detecting escaped refrigerant with the sensor;   operating the gas pump in response to the detected escaped refrigerant; and   using the gas pump to direct air and escaped refrigerant to contact the refrigerant retention material in the refrigerant retention device, whereby the escaped refrigerant will be retained by the refrigerant retention material.   
     
     
         18 . The method of  claim 17 , further comprising the step of removing and replacing the refrigerant retention material. 
     
     
         19 . The method of  claim 17 , further comprising the step of regenerating the refrigerant retention material. 
     
     
         20 . The method of  claim 17 , wherein air discharged from the vent has a concentration of refrigerant below the critical combustion concentration for the refrigerant in air.