Air Source Heat Pump:Four Major Components

2016-09-28 15:26:16 alice 19

The air source heat pump mainly consists of compressor, expansion valve, finned heat exchanger and double-pipe heat exchanger. Through the input of the electric energy drives the compressor, the electrical machinery to work, making the fin heat exchanger absorb the heat, the double-pipe heat exchanger release the heat. The heat effect is up to 380%. Heat pump is one of the most energy-saving heat source equipment. Safety, environmental protection and high efficiency are its main features. 


Key Component – the Compressor

Compressor as the key component of air source heat pump, like computer CPU, and heart of human, only can he drive the flow of refrigerant to achieve the process of thermal expansion and contraction( evaporation and condensation). Currently, Panasonic, Daikin, Copeland and Hitachi brands are known as the HVAC compressor industry’s four major brands


Throttle device – capillary, electronic expansion valve and thermal expansion valve

Throttle valve includes capillary throttle, thermal expansion valve (internal balance, external balance) and electronic expansion valve, which is by changing the refrigerant pressure to help the refrigerant achieving liquefaction and gasification, as well as detects and collects the information of temp. difference between inlet and outlet, air return temp., and other setting parameters.  After microprocessor processing, the opening of expansion valve is controlled to meet the system load requirements. Electronic expansion valve has the advantage of being able to precisely control the refrigerant flow, so as to achieve precise control of evaporation temperature. Usually, it installs in high accuracy temperature control unit.

Electronic expansion valve can work normally above -70 , but thermal expansion valve only above -60 , while Capillary is used in small refrigeration systems (simple structure, non-adjustable. After all, it just a small copper tube only);

Expansion valve is used in medium-sized and large refrigeration system (the structure is relatively complex, adjustable), which can adjust the refrigerant flow the evaporator and the condenser. When the evaporating conditions working, if the condensation pressure is too high, can properly close the expansion valve to reduce the system flow of refrigerant and the condenser load, thereby lower the condensing pressure to achieve high efficiency and reliable operation.


Heat Exchanger

Finned heat exchanger


high heat transfer efficiency, due to the turbulence of the fin to the fluid, boundary layer constantly ruptured, which causes a large heat transfer coefficient; What’s more, because the fin is thin, the thermal conductivity is high, making plate-fin heat Device can achieve high efficiency.

compact, because the plate-fin heat exchanger with an expanded secondary surface, making its surface area up to 1000m2 / m3.

Lightweight, because of compactness structure and aluminum material, and now steel, copper, composite materials, etc. have also been available mass production


Double-pipe Heat Exchanger

Double-pipe heat exchanger is the carrier transferring the heat to water, which choose high-performance thread-shaped copper pipe, and galvanized steel pipe, to achieve the process of refrigerant surrounding water, letting high-temperature refrigerant gas fully contact with water to reach the best heat transfer effect.