Patent ID: 7500368

Claim:
A method for adjusting a refrigerant charge of an air conditioning system, the method comprising: computing a delta temperature split; comparing the delta temperature split to a delta temperature split threshold; if the absolute value of the delta temperature split is less than the delta temperature split threshold, ending the method; if the delta temperature split is less than minus the delta temperature split threshold, and the air conditioning system is not a Thermostatic Expansion Valve (TXV) system: computing one of the a refrigerant undercharge and a refrigerant overcharge based on a superheat temperature; if the delta temperature split is less than minus the delta temperature split threshold, and the air conditioning system is the TXV system: computing one of the refrigerant undercharge and the refrigerant overcharge based on subcooling temperature; and adjusting the amount of refrigerant in the air conditioning system based on one of the refrigerant undercharge and the refrigerant overcharge.