What is the operating principle of air source heat pump?

What is the operating principle of air source heat pump?

As an efficient, energy-saving and environmentally friendly heating and cooling equipment, air source heat pump occupies an important position in the field of modern energy utilization. air source heat pump's operating principle is based on the concept of heat transfer, which cleverly utilizes the thermal energy in the air to achieve energy transfer and improvement, and has many significant advantages. The following will elaborate on the operating principle and advantages of air source heat pumps:

Basic working cycle

The air source heat pump is mainly composed of four core components: evaporator, compressor, condenser and expansion valve. air source heat pump's working process forms a closed cycle system.

1. Evaporator - heat extraction

The evaporator is a key component for heat exchange between the air source heat pump and the outside air. In the evaporator, low-temperature and low-pressure liquid refrigerant (such as Freon) enters after being throttled and decompressed by the expansion valve. At this time, the boiling point of the refrigerant is greatly reduced, and it quickly evaporates and vaporizes in the evaporator. Since a large amount of heat needs to be absorbed from liquid to gaseous state, and the air temperature around the evaporator is relatively high, heat is transferred from the air to the refrigerant, causing the refrigerant to evaporate into a low-temperature and low-pressure gaseous state, and the air is cooled. This process achieves the purpose of absorbing heat from the air, just like extracting free heat from the huge "heat reservoir" of nature.

2. Compressor - energy improvement

The low-temperature and low-pressure gas refrigerant coming out of the evaporator is sucked into the compressor, and the compressor compresses it and performs work. Under the strong compression of the compressor, the pressure and temperature of the refrigerant increase sharply and become a high-temperature and high-pressure gas. At this time, the energy contained in the refrigerant is significantly increased. Just like pumping water from a lower place to a higher place through a water pump increases the potential energy of the water, the compressor provides energy to the refrigerant so that it has the ability to release heat to a high-temperature environment. .

3. Condenser - release of heat 

The high-temperature and high-pressure gaseous refrigerant then enters the condenser. The condenser is usually connected to the indoor space that needs heating (such as floor heating pipes, radiators, etc.) or to the domestic hot water tank. Since the temperature of the refrigerant is higher than the temperature of the indoor environment or the water in the water tank, heat is transferred from the refrigerant to the indoor space or water, causing the indoor temperature to rise or the water to be heated. During this process, the gaseous refrigerant gradually condenses and liquefies after releasing heat, and returns to the liquid state, completing the key step of transporting heat from the air to the room or water.

4. Expansion valve - circulation control

After the liquid refrigerant flows out of the condenser, it passes through the expansion valve. The function of the expansion valve is to throttle and depressurize the refrigerant, causing its pressure and temperature to drop again and return to the low-temperature and low-pressure state when it enters the evaporator, preparing for the next round of heat-absorbing evaporation process in the evaporator. The expansion valve is like a flow regulating valve, accurately controlling the flow and pressure of the refrigerant to ensure that the entire air source heat pump system can operate stably and efficiently.

Through such a continuous cycle process, the air source heat pump can continuously absorb heat from the air and raise it to a higher temperature level for indoor heating, making domestic hot water or achieving refrigeration function in summer ( By switching the flow direction of the refrigerant, the heat in the room is transferred to the outdoor air)