1. Working principle of precision cooling system

In the vapor compression refrigeration system, the compressor, condenser, throttling device, and evaporator are four essential parts.

Evaporator: conveying cold capacity equipment, in which the refrigerant absorbs the heat of the object to be cooled to achieve evaporative refrigeration;

Compressor: the heart of the refrigeration system, which plays the role of inhaling, compressing, and transporting refrigerant vapor;

Condenser: a device that releases heat, and transfers the heat absorbed in the evaporator together with the heat converted by the power consumption of the compressor to the cooling medium;

Throttling device: The refrigerant plays the role of throttling and reducing pressure, and at the same time controls and adjusts the amount of refrigerant liquid entering the evaporator, and divides the system into two parts: the high-pressure side and the low-pressure side.

In the actual refrigeration system, in addition to the above four major components, there are some auxiliary equipment, such as:

 Solenoid valve;

 One-way valve;

 Allocator;

 Filter drier;

 Temperature sensor;

 Pressure controller;

 .........

They are designed to improve the safety, reliability, and economy of refrigeration and air-conditioning systems.

2. Classification of precision cooling host types

Water-cooled chilled water precision cooling unit: It uses water as the cold and heat source, and its condensing side is a water heat exchanger, which needs to work through the cooling water circulation pump and is used in conjunction with the cooling tower.

Air-cooled chilled water precision cooling unit: The ambient air is used as the cold and heat source, and the condensing side of the host is a finned tube heat exchanger plus a fan motor.

Multi-connected precision cooling unit: The multi-connected system is simple, just connect the indoor and outdoor units with refrigerant copper pipes; the refrigerant and air directly exchange heat, so the heat exchange efficiency is high. Each room can be controlled individually.

Air-cooled scroll heat pump unit: its fan releases heat into the air, and the scroll compressor provides hot and cold water. Generally, multiple models can be combined for expansion; the heat pump unit can realize cooling and heating through the four-way valve reversing of the refrigeration system. The air-cooled scroll chiller has no four-way valve and can only cool.

Water-cooled centrifugal chiller: water-cooled: no air-cooled heat exhaust, through the circulating cooling water through the cooling tower to indirectly exhaust heat to the atmosphere; centrifugal: adopt centrifugal compressor, the capacity is usually above 500RT; cold water: produces cold water, discharge to the circulating chilled water Cold, the refrigerant only circulates in the main unit.

Water-cooled screw chiller: water-cooled: no air-cooled heat exhaust, through the circulating cooling water through the cooling tower to indirectly exhaust heat to the atmosphere; screw: screw compressor, the capacity is usually below 500RT; cold water: produces cold water, discharge to the circulating chilled water Cold, the refrigerant only circulates in the main unit.

Water-cooled vortex chiller: Water-cooled: no air-cooled heat discharge, through the circulating cooling water through the cooling tower to indirectly discharge heat to the atmosphere; vortex: use vortex refrigeration compressors; cold water: produce cold water, discharge cooling to circulating refrigerated water, The refrigerant circulates only in the main unit.