The air-cooled heat pump cold and hot water unit has high equipment utilization rate as the cold and heat source of the central air conditioner. One machine is dual-use in winter and summer, eliminating the cooling water system and heating boiler required for water-cooled chiller, which has positive significance for water saving, energy saving and environmental protection. And it is easy to install and can be placed on the roof without occupying building area. It is widely used in the Yangtze River Basin and the south of the Yangtze River.
The water-side heat exchangers of small villas and modular air-cooled heat pump chiller and heater units are sleeve type, plate type and vertical coil type. The refrigerant water heat exchanger in the heat pump type hot and cold water unit is more suitable to use corrugated internally threaded pipes.Various heat exchangers have their own characteristics. For sleeve and vertical coil heat exchangers, you must pay attention to solving their main problems during design and manufacture. The use of plate heat exchangers should also make users understand its characteristics. At the same time, it should be paid to water quality issues. The water-side heat exchanger has effective anti-freeze protection.
The small air-cooled heat pump hot water unit uses a force expansion valve. The four check valves control the cooling and heating directions. It also uses a capillary tube to assist in throttling during heating.Due to the large changes in refrigerant circulation in different working conditions of refrigeration and heating, medium and large units require two or more thermal expansion valves to meet the requirements of the working conditions.In the case where the resistance of the liquid pipeline is large, it is necessary to pay attention to appropriately increasing the empty amount of the corresponding expansion valve, so as to avoid the shortage of liquid supply.