System and Method For Charging HVAC System

Abstract

A method of charging an HVAC system by determining a relationship between a liquid line temperature of the HVAC system, a suction line pressure of the HVAC system, and an ambient outdoor temperature of the HVAC system. A method of charging an HVAC system by adjusting a mass of refrigerant in the HVAC system to approach a target minimum liquid line temperature. A method of charging an HVAC system by testing the HVAC system according to at least three sets of test parameters, two of the three sets of test parameters comprising testing the HVAC system at substantially a same outdoor ambient temperature and at least one of the remaining set of test parameters comprising testing the HVAC system at a different outdoor ambient temperature.

1 . A method of charging an HVAC system, comprising:
 determining a relationship between a liquid line temperature of the HVAC system, a suction line pressure of the HVAC system, and an ambient outdoor temperature of the HVAC system.   
     
     
         2 . The method according to  claim 1 , generating an equation for estimating the liquid line temperature wherein the equation is based on the determined relationship. 
     
     
         3 . The method of  claim 1 , further comprising:
 generating a plurality of charging curves based on the determined relationship;   wherein each of the charging curves is associated with a separate outdoor ambient temperature.   
     
     
         4 . The method of  claim 1 , further comprising:
 generating a charging chart based on the determined relationship, the chart comprising a matrix of liquid line temperature values as a function of various suction line pressures of the HVAC system and various ambient outdoor temperatures of the HVAC system.   
     
     
         5 . The method of  claim 4 , wherein at least one of the liquid line temperature values lies at the intersection of a suction line pressure value row and an outdoor ambient temperature column. 
     
     
         6 . The method of  claim 4 , wherein at least one of the liquid line temperature values lies at the intersection of a suction line pressure value column and an outdoor ambient temperature row. 
     
     
         7 . The method of  claim 4 , wherein the charging chart comprises at least one maximum liquid line pressure value associated with an outdoor ambient temperature. 
     
     
         8 . A method of charging an HVAC system, comprising:
 adjusting a mass of refrigerant in the HVAC system to approach a target minimum liquid line temperature.   
     
     
         9 . The method of  claim 8 , wherein the target minimum liquid line temperature is determined as a function of a suction line pressure of the HVAC system and an outdoor ambient temperature of the HVAC system. 
     
     
         10 . The method of  claim 8 , wherein refrigerant is added to the HVAC system in response to a measured liquid line temperature being above the target minimum liquid line temperature. 
     
     
         11 . The method of  claim 8 , wherein refrigerant is removed from the HVAC system in response to a measured liquid line pressure being higher than a maximum allowable liquid line pressure. 
     
     
         12 . The method of  claim 8 , wherein refrigerant is removed from the HVAC system in response to a measured liquid line temperature being lower than the target minimum liquid line temperature. 
     
     
         13 . A method of charging an HVAC system, comprising:
 testing the HVAC system according to at least three sets of test parameters, two of the three sets of test parameters comprising testing the HVAC system at substantially a same outdoor ambient temperature and at least one of the remaining set of test parameters comprising testing the HVAC system at a different outdoor ambient temperature.   
     
     
         14 . The method of  claim 13 , further comprising:
 determining a relationship between a liquid line temperature of the HVAC system, a suction line pressure of the HVAC system, and an ambient outdoor temperature of the HVAC system wherein the relationship is based on test data obtained by testing the HVAC system.   
     
     
         15 . The method of  claim 14 , further comprising:
 generating a charging chart comprising a matrix of target minimum liquid line temperature values.   
     
     
         16 . The method of  claim 14 , further comprising:
 generating an equation for estimating the liquid line temperature wherein the equation is based on the determined relationship.   
     
     
         17 . The method of  claim 14 , further comprising:
 measuring the suction line pressure;   measuring the outdoor ambient temperature;   measuring the liquid line temperature; and   adjusting a charge of the HVAC system in response to the measured liquid line temperature of the HVAC system.   
     
     
         18 . The method of  claim 17 , wherein the adjusting of the charge is performed in response to a comparison between the measured liquid line temperature and a target minimum liquid line temperature. 
     
     
         19 . The method of  claim 15 , wherein a target minimum liquid line temperature is determined from the matrix based on a measured suction line pressure of the HVAC system and a measured outdoor ambient temperature of the HVAC system. 
     
     
         20 . The method of  claim 16 , wherein a target minimum liquid line temperature is calculated using the equation based on a measured suction line pressure of the HVAC system and a measured outdoor ambient temperature of the HVAC system.