DETERMINING METHOD OF NECESSARY SEALING AMOUNT OF REFRIGERANT FOR REFRIGERATING CYCLE AND DEVICE THEREFOR AS WELL AS NECESSARY AMOUNT OF REFRIGERANT SEALING DEVICE

摘要

PURPOSE:To determine the necessary sealing amount of refrigerant for a refrigerating cycle properly and, further, seal the necessary amount-of refrigerant even when the length of a liquid pipeline is not known. CONSTITUTION:In a refrigerating cycle, consisting of an outdoor machine 8, indoor machines 9, 10, a liquid pipeline 11 and a gas pipeline 12 and into which refrigerant is not sealed yet, expansion valves 8a, 9a, 10a and an on/off valve 13 for servicing are fully opened. In this case, a pressure P2 in the refrigerating cycle is an atmospheric pressure in this example. Next, when a sealed vessel 2, into which the air of a pressure P1 is sealed and whose internal volume V1 is known, is connected to the valve 13 through a connecting tube 7 and a valve 6 is opened to communicate the refrigerating cycle with the sealed vessel 2, the pressures of both of them are balanced. A pressure P3 that time and the air pressure P1 are detected by a pressure detector 3. A microcomputer 4 operates the internal volume of the refrigerating cycle from differences P1-P3, P3-P2, and the internal volume V1 and, further, operates the necessary sealing amount of refrigerant for the refrigerating cycle employing known functional relations, then, indicates them on an indicating device 5. Thereafter, the device is evacuated and the necessary amount of refrigerant is sealed automatically from a bomb into the refrigerating cycle in some embodiment.