Building energy saving At present, the difficulty encountered in the use of inverter compressors is that the refrigeration capacity of inverter compressors on the market is not large, generally below 5 kW. At the same atmospheric temperature, the evaporation temperature of the unit is lower on the surface of the finned tube than when it is frost-free, and when the frost layer reaches a certain thickness, the evaporation temperature will decrease significantly. The working range of the inverter compressor is limited. If some inverter compressors are required to operate above the evaporation temperature of -6.8e, the inverter compressor is not suitable for the heat pump system, and the technical level of the inverter compressor is still to be used. Improve and so on. To this end, the development and research work of the inverter compressor system should be strengthened. The frequency conversion technology has been promoted and used in small air-cooled hot and cold water units. How to quickly establish a large flow rate after defrost start is a fundamental measure to reduce the defrost time, which includes reducing the time for the refrigerant to be withdrawn from the gas-liquid separator and how to increase the condensation and evaporation pressure without causing the system to operate. Low, so that the mass flow rate in the system increases rapidly. Two measures can be taken: 1) replacing the gas-liquid separator with a gas-liquid heat exchanger, and heating the refrigerant entering the compressor with the compressor exhaust gas, and ensuring Inhalation without liquid, which is equivalent to improving the heat exchange conditions of the gas-liquid separator, so that the refrigerant can be put into operation without pulling the evaporation pressure extremely low, and the exhaust cooling condition of the compressor is also improved; 2) The compressor exhaust is bypassed to the suction side of the compressor, which not only allows the refrigerant in the gas-liquid separator to evaporate rapidly but also increases the evaporation pressure, so that the mass flow rate in the system is rapidly increased, thereby increasing the condensing pressure. DIN Rail Enclosures,din rail,din rail enclosure,din rail housing,din rail cutter wybox inc. , https://www.wybox.com