The working principle of cooling and heating of air conditioning
In addition to the cooling function, the heating and cooling air conditioner also has the heating function. The biggest difference from a single-cooling air conditioner is that an electromagnetic four-way reversing valve is installed in the heating and cooling air conditioner. It is a key component to realize the switching between cooling and heating. Now let's introduce the cooling and heating process of heating and cooling air conditioners in detail.
How Refrigeration Works
During the refrigeration operation, the refrigerant is compressed in the compressor, the original low-temperature and low-pressure refrigerant gas is compressed into high-temperature and high-pressure superheated vapor, and then discharged from the compressor discharge port. Unlike single-cooling air conditioners, heating and cooling air conditioners control the flow of refrigerant through an electromagnetic four-way reversing valve. The high temperature and high pressure superheated steam enters from the inlet of the four-way valve. Since the compressor exhaust pipe is connected to the condenser of the outdoor unit through the four-way valve in the refrigerating state, the high-temperature and high-pressure superheated steam is introduced into the cold condenser through the four-way valve.
The high-temperature and high-pressure superheated vapor is cooled in the condenser, and the superheated refrigerant changes from a gaseous state to a liquid state through the cooling and heat dissipation of the fan. The heating and cooling air conditioner is equipped with a one-way valve between the indoor evaporator and the outdoor condenser, which is used to control the flow direction of the refrigerant and has the function of one-way conduction and reverse blocking. When the cooled low-temperature and high-pressure refrigerant flows through, the one-way valve in the refrigeration system is turned on and the heating one-way valve is turned off.
Therefore, after the refrigerant liquid passes through the one-way valve, it passes through the filter drier and capillary tube throttling and pressure reduction, and the low-temperature and low-pressure refrigerant liquid flows into the indoor unit through the liquid pipe (thin pipe).
The refrigerant liquid absorbs heat and vaporizes in the evaporator of the indoor unit, the temperature of the surrounding air temperature drops, and the cold air is blown into the room by the cross flow fan.
The vaporized refrigerant is then sent back to the outdoor unit through the gas pipe (thick pipe). At this time, the four-way valve connects the indoor evaporator pipe to the compressor suction pipe, so that the refrigerant gas can be sucked by the compressor suction port. In the compressor, it is compressed into high-temperature and high-pressure superheated steam again to maintain the refrigeration cycle.
Working principle of heating
When the heating and cooling air conditioner is heating, the high temperature and high pressure superheated steam compressed by the compressor is discharged from the exhaust port of the compressor, and then the superheated steam is directly sent to the indoor unit evaporator through the connecting indoor evaporator pipe through the four-way valve. At this time, the evaporator of the indoor unit acts as a condenser. The superheated steam passes through the heat exchanger of the indoor unit to dissipate heat, and the radiated heat is blown out from the tuyere by the cross-flow fan.
The superheated steam is cooled to form a low-temperature and high-pressure liquid, which is then sent back from the indoor unit to the outdoor unit by a liquid pipe (thin pipe). At this time, in the heating cycle, the heating check valve is turned on and the cooling check valve is turned off according to the flow direction of the refrigerant. The refrigerant liquid is sent to the condenser of the outdoor unit after the throttling components such as the heating one-way valve, the filter drier and the hair tube.
Contrary to the function of the indoor unit evaporator, the function of the condenser is equivalent to the function of the indoor unit evaporator during cooling. The low-temperature and low-pressure refrigerant completes the vaporization process here. The refrigerant liquid absorbs a large amount of heat from the outside and becomes a dry saturated vapor again, and the cold air is blown out from the outdoor unit by an axial fan. The dry saturated steam finally enters through the pipe port connected to the outdoor condenser, and returns to the compressor suction port through the compressor suction pipe to continue the second heating cycle.
It can be seen that the heating cycle and the refrigeration cycle are exactly the opposite. In the cooling process, the heat exchanger of the indoor unit functions as an evaporator, and the heat exchanger of the outdoor unit functions as a condenser. Therefore, during cooling, the outdoor unit blows hot air and the indoor unit blows cold air. During the heating cycle, the heat exchanger of the indoor unit functions as a condenser, and the heat exchanger of the outdoor unit functions as an evaporator. Therefore, during heating, the indoor unit blows hot air, while the outdoor unit blows cold air.
