How to drain, test and debug the refrigeration system 1. The purpose of blowdown of the refrigeration system is to ensure the internal cleanliness of the system. If there are various impurities and powders remaining in the system, it will cause the blockage of the cooling pipe of the throttle hole, and cause minor problems such as fluffing and increased friction during operation. It will cause damage to the refrigeration system; 2. Relevant content about leak detection of refrigeration system a. The leak detection basis of the refrigeration system must be determined according to the type of refrigerant selected, the cooling method of the refrigeration system and the position of the pipe section; b. For high-pressure systems, the leak detection pressure should generally be planned at about 1.25 times the condensing pressure, which is convenient for observation and more intuitive without damaging the refrigeration system; c. The leak detection pressure of the low-pressure system generally refers to 1.2 times the saturation pressure in summer; 2. Relevant content about the debugging of refrigeration system 1. Check whether the opening and closing status of each valve in the refrigeration system is normal, especially the exhaust shut-off valve must be kept open; 2. Check whether the cooling water valve of the water condenser is open, and whether the rotation of the fan of the wind condenser is normal; 3. Before starting the refrigeration system, it is necessary to test whether the electrical control circuit is correct and measure whether the voltage of the power supply is normal; 4. Confirm whether the oil level of the crankcase of the refrigeration compressor is normal and adheres to the horizontal median line of the sight glass; 5. Start the refrigeration compressor and check whether it is running normally. For example, is the direction of rotation correct? Is the running sound normal? 6. After starting the refrigeration compressor, observe whether the value of the high and low pressure gauges of the compressor is reasonable; 7. Under operating conditions, listen to the sound of refrigerant flowing in the expansion valve and check whether there is condensation or frost in the pipeline behind the expansion valve. The normal refrigeration system works at full load in the early stage of operation, which can be understood by the temperature of the cylinder head; 8. When debugging refrigeration equipment, make sure that the high and voltage pressure relays, oil pressure differential relays, cooling water and chilled water cut-off relays, chilled water freezing protection relays and safety valves of the system are in normal working conditions;