Refrigerant Service Hose Check Valve Device and Method

Abstract

A service hose includes a service coupler and a check valve assembly. The service coupler is configured to fluidly connect the service hose to a refrigeration system. The check valve assembly is disposed proximal to the service coupler and includes a recovery and a recharge flow path. The recovery flow path is defined by a flow of a refrigerant from the refrigeration system and flows along a first bore disposed in a body having a recovery poppet. The recharge flow path is defined by a flow of the refrigerant to the refrigeration system and flows along a second bore disposed in the body, a recharge poppet, and a biasing member. The check valve assembly is configured to provide a substantially free flow of refrigerant along the recovery flow path and also configured to provide a predetermined cracking pressure in response to the refrigerant being urged to flow along the recharge flow path.

What is claimed is: 
     
         1 . A refrigerant recovery system, comprising:
 a service hose, including:   a service coupler configured to fluidly connect the service hose to a refrigeration system;   a check valve assembly disposed proximal to the service coupler, the check valve assembly including:   a recovery flow path defined by a flow of a refrigerant from the refrigeration system and flowing along a first bore disposed in a body, a recovery poppet, a first O-ring, and a stand-off; and   a recharge flow path defined by a flow of the refrigerant to the refrigeration system and flowing along a second bore disposed in the body, a recharge poppet, a second O-ring, a biasing member, and a shim;   a hose to convey refrigerant, wherein the check valve assembly is configured to provide a substantially free flow of refrigerant along the recovery flow path and the check valve assembly is configured to provide a predetermined cracking pressure in response to the refrigerant being urged to flow along the recharge flow path; and   a refrigerant recovery unit, including:   a refrigerant storage unit configured to store the refrigerant;   a refrigerant circuit in fluid connection with the refrigeration system, the refrigerant circuit configured to recover refrigerant from the refrigeration system and recharge the refrigeration system with the refrigerant;   a processor configured to control the refrigerant recovery unit; and   a memory to store diagnostic software and operating software to operate the refrigerant recovery unit.   
     
     
         2 . The refrigerant recovery system according to  claim 1 , further comprising:
 a second service coupler configured to fluidly connect the service hose to the refrigeration system.   
     
     
         3 . The refrigerant recovery system according to  claim 1 , wherein the biasing member is a spring. 
     
     
         4 . The refrigerant recovery system according to  claim 1 , wherein the refrigerant recovery unit further comprises:
 an input interface configured to receive an input from a user; and   a display configured to display information to the user.   
     
     
         5 . The refrigerant recovery system according to  claim 1 , wherein the predetermined cracking pressure is selected to maintain the refrigerant disposed in the hose being recharged into the refrigeration system in a liquid state. 
     
     
         6 . The refrigerant recovery system according to  claim 1 , wherein the refrigerant recovery unit further includes a compressor to urge the refrigerant to flow through the refrigerant circuit and the compressor is configured to supply the refrigerant to the service hose at or greater than the predetermined cracking pressure. 
     
     
         7 . The refrigerant recovery system according to  claim 1 , wherein the recovery poppet is configured to seal upon the first O-ring in response to a supply of the refrigerant flowing into the service hose from the refrigerant recovery unit. 
     
     
         8 . The refrigerant recovery system according to  claim 1 , wherein the refrigerant recovery unit is further configured to recover and recharge the refrigerant in the refrigeration system. 
     
     
         9 . The refrigerant recovery system according to  claim 1 , wherein the refrigerant recovery unit further includes an oil separator to remove oil from the refrigerant. 
     
     
         10 . The refrigerant recovery system according to  claim 1 , further comprising:
 a second service hose to fluidly connect the refrigeration recovery unit to the refrigeration system.   
     
     
         11 . A service hose, comprising:
 a service coupler configured to fluidly connect the service hose to a refrigeration system; and   a check valve assembly disposed proximal to the service coupler, the check valve assembly including:
 a recovery flow path defined by a flow of a refrigerant from the refrigeration system and flowing along a first bore disposed in a body, a recovery poppet, a first O-ring, and a stand-off; and 
 a recharge flow path defined by a flow of the refrigerant to the refrigeration system and flowing along a second bore disposed in the body, a recharge poppet, a second O-ring, a biasing member, and a shim, wherein the check valve assembly is configured to provide a substantially free flow of refrigerant along the recovery flow path and the check valve assembly is configured to provide a predetermined cracking pressure in response to the refrigerant being urged to flow along the recharge flow path. 
   
     
     
         12 . The service hose according to  claim 11 , wherein the biasing member is a spring. 
     
     
         13 . The service hose according to  claim 11 , further comprising:
 a hose to convey the refrigerant between the refrigeration system and a refrigerant recovery unit.   
     
     
         14 . The service hose according to  claim 13 , wherein the recovery poppet is configured to seal upon the first O-ring in response to a supply of the refrigerant flowing into the service hose from the refrigerant recovery unit. 
     
     
         15 . The service hose according to  claim 12 , wherein the biasing member is configured to urge the recharge poppet to seal upon the second O-ring to provide the predetermined cracking pressure. 
     
     
         16 . A method of servicing a refrigeration system, the method comprising the steps of:
 recovering a refrigerant from the refrigeration system with a refrigeration recovery unit, the refrigeration recovery unit being in fluid communication with the refrigeration system via a service hose, the service hose including:   a service coupler configured to fluidly connect the service hose to the refrigeration system;   a check valve assembly disposed proximal to the service coupler, the check valve assembly including:   a recovery flow path defined by a flow of the refrigerant from the refrigeration system and flowing along a first bore disposed in a body, a recovery poppet, a first O-ring, and a stand-off; and   a recharge flow path defined by a flow of the refrigerant to the refrigeration system and flowing along a second bore disposed in the body, a recharge poppet, a second O-ring, a biasing member, and a shim; and   a hose to convey refrigerant, wherein the check valve assembly is configured to provide a substantially free flow of refrigerant along the recovery flow path and the check valve assembly is configured to provide a predetermined cracking pressure in response to the refrigerant being urged to flow along the recharge flow path; and   recharging the refrigeration system with the refrigerant by urging the refrigerant to flow from the refrigeration recovery unit at a pressure greater than the predetermined cracking pressure of the check valve assembly.   
     
     
         17 . The method according to  claim 16 , further comprising the step of:
 determining a recharge weight of refrigerant in response to a recommended weight of refrigerant for the refrigeration system and a weight of refrigerant remaining in the service hose.   
     
     
         18 . The method according to  claim 16 , further comprising the step of:
 determining the predetermined cracking pressure in response to a pressure the refrigerant is in liquid state at ambient temperature.   
     
     
         19 . The method according to  claim 18 , further comprising the step of:
 determining a tension for the biasing member based on the determined predetermined cracking pressure.   
     
     
         20 . The method according to  claim 16 , further comprising the step of:
 recovering the refrigerant from the service hose in response to the service coupler being fluidly disconnected from the refrigeration system.