Air energy heat pump has four core components: compressor, condenser, expansion valve and evaporator. So what are their functions? Let's have a look!
(1) Expansion valve (throttle valve)
Expansion valve (throttle valve) is a device that controls the flow of refrigerant by changing the throttle section or throttle length in the heating system, which is generally installed between the evaporator and the liquid storage cylinder. The expansion valve (throttle valve) throttles the medium temperature and high pressure liquid refrigerant into low temperature and low pressure wet vapor, and then the refrigerant absorbs heat from the outside air in the evaporator. The expansion valve (throttle valve) controls the valve flow rate through the change of the superheat at the end of the evaporator to prevent under-utilization of the evaporator area and the occurrence of cylinder knocking phenomenon.
The compressor is a fluid mechanical device that can elevate low-pressure gas to high-pressure gas, and it is the heart of the heating system. It sucks low-temperature and low-pressure refrigerant gas from the suction pipe, drives the piston to compress it through the operation of the motor, and then discharges the high-temperature and high-pressure refrigerant gas to the exhaust pipe, so as to provide power for the heating cycle of compression → condensation (heat release) → expansion → evaporation (heat absorption).
The condenser as a part of the heating pump system is a kind of heat exchanger. It can convert gas or vapor into liquid, and heat the water in the tube in a fast manner. The gas passes through a long tube (usually coiled into a solenoid), allowing the heat to be dissipated into the surrounding water, and the metals such as copper, which have strong thermal conductivity, are often used to transport steam. In order to improve the efficiency of the condenser, the heat sink with excellent thermal conductivity is often added to the pipeline to increase the heat dissipation area, so as to accelerate heat dissipation. The working process of the condenser is an exothermic process, so the condenser works at a relatively high temperature.
The evaporator is a very important part of the four major components. After being compressed and liquefied, the low-temperature refrigerant passes through the evaporator to exchange heat with the outside air. The process of evapouration absorbs heat and reduces the temperature of the surrounding air, which will achieve the purpose of absorbing energy in the air.