What should be paid attention to during the debugging operation of air cooled water chillers?

　　What should be paid attention to during the debugging operation of air cooled water chillers?

　　1. Pressure and leakage test:

　　Close the valves in the air-cooled chiller unit that are connected to the external environment, inject dry nitrogen into the system, and stop nitrogen filling when the system pressure reaches 10-15 bar. Use soapy water to test all welding components, threaded connections, valve connections, and other positions for leaks, and maintain the system pressure for 24 hours. If the pressure remains basically unchanged, it indicates that the system is well sealed and the nitrogen used to maintain the pressure can be released.

　　2. Adding lubricating oil:

　　The lubricating oil specified by the compressor manufacturer must be used. Firstly, open all valves on the oil circuit and inject lubricating oil into the oil separator from the inlet valve (some units have oil injection valves on the oil separator, while others have oil injection valves in front of the oil filter). The amount of oil is usually added in the middle of the sight glass of the oil separator. Then inject about 1% of the total refrigerant into the oil separator to ensure that the oil can flow from the oil separator into the oil cooler and the system Oil pipeline.

　　The container for storing lubricating oil must be sealed to prevent it from absorbing moisture in the environment.

　　3. Vacuum pump:

　　Install all dry filter elements before vacuuming. Turn on the oil heater (set at 40-45 ℃). Close the valve connecting the system to the atmosphere and open the valve between the unit and other equipment. Most drying filters are equipped with refrigerant charging valves (charging valves) near them, and vacuum pump pipelines are connected from them. It is generally not allowed to use the unit itself for vacuum cleaning.

　　4. Charging refrigerant:

　　After vacuuming, refrigerant can be added from the charging valve in front of the drying filter. The size and model of other equipment in the system (such as evaporators, condensers, liquid receivers, etc.) will affect the refrigerant filling capacity, so it can be filled based on theoretical calculations.

　　(1) Check if the lubricating oil is at 30 ℃. If at 30 ℃, it should turn on the electric heater for heating and activating the oil pump to ensure the temperature uniformity of the lubricating oil circulation increase.

　　(2) Adjust the system oil pressure to control the regulating valve, so that the oil pressure does not reach 0.5-O.6MPa.

　　(3) Turn off the power supply of the compressor, start the control switch, open the suction valve of the compressor, start the compressor after the delay, and adjust the lubricating oil pressure after the compressor runs to 0.15~0.3MPa. Above exhaust pressure

　　(4) Close the solenoid valve control circuit in the liquid supply pipeline, activate the solenoid valve, supply liquid refrigerant to the evaporator, place the energy regulator in the load position, and gradually increase the load over time. Simultaneously observed the attraction pressure. By adjusting the expansion valve, the suction pressure stabilizes between 0.36 and 0.56 MPa.