Patent ID: 6708508
Filing Date: 2004-03-23
Classification: B60H,F25B

Abstract:
A method of refrigerant level monitoring in a refrigerant circuit of an air-conditioning or heat-pump system having a compressor and a refrigerant which may, depending on the operating point, be operated in the supercritical range, the method comprising:at least standstill level monitoring with the compressor switched off, comprising measuring both the pressure (pKM) and the temperature (TKM) of the refrigerant, and determining whether the measured refrigerant pressure lies below a temperature-independent predetermined minimum pressure value (pmin) or whether the measured refrigerant temperature lies above a predetermined maximum saturation temperature value (TS) and the measured refrigerant pressure lies outside a predetermined target pressure range (pu, po), in each case as an indication of improper filling.