In the refrigeration system, the evaporator, the condenser, the compressor and the throttle valve are the four essential parts in the refrigeration system, among which the evaporator is the equipment to transport the cold volume. In which the refrigerant absorbs the heat of the cooled object to achieve refrigeration. The compressor is the heart, playing the role of suction, compression, transport refrigerant vapor. The condenser is a device that releases heat. The heat absorbed in the evaporator and the heat transformed by the work of the compressor are transferred to the cooling medium to take away. The throttle valve acts to throttle and reduce the pressure of the refrigerant, and controls and regulates the amount of refrigerant liquid flowing into the evaporator. The system is divided into two parts: high pressure side and low pressure side. In the actual refrigeration system, in addition to the above four pieces, there are often some auxiliary equipment, such as solenoid valve, distributor, dryer, collector, fusible plug, pressure controller and other components, they are set to improve the operation of the economy, reliability and safety.

According to the condensation form, the air conditioner can be divided into water-cooled type and air-cooled type. According to the purpose of use, it can be divided into single cooling type and refrigeration warm type. No matter which type of composition, it is composed of the following main components.

The necessity of condenser is based on the second law of thermodynamics. According to the second law of thermodynamics, the spontaneous flow direction of heat energy in a closed system is unidirectional, that is, it can only flow from high heat to low heat, and the microscopic particles carrying heat energy can only change from order to disorder in the microscopic world. Therefore, when a heat engine has energy input to do work, it must also have energy released downstream. In this way, there will be a heat gap between upstream and downstream, and the flow of heat energy will be possible, and the cycle will continue.

Therefore, if you want the load to do work again, you must first release the heat energy that has not been fully released, and at this time, you need to use the condenser. If the surrounding heat energy is higher than the temperature in the condenser, in order to cool the condenser, work must be done artificially (generally using a compressor). The condensed fluid reverts back to a state of high order and low thermal energy and can do work again.

The selection of condenser includes the selection of form and model, and the determination of the flow rate and resistance of cooling water or air flowing through the condenser. The selection of condenser type should consider the local water source, water temperature, climate conditions, as well as the total cooling capacity of the refrigeration system and the layout requirements of the refrigeration room. On the premise of determining the condenser type, the heat transfer area of the condenser is calculated according to the condensing load and the heat load per unit area of the condenser, so as to select the specific model of the condenser.