I. Cold Storage Refrigeration Principle
The refrigeration principle of cold room is to remove heat from the interior of the cold storage unit using a refrigeration unit, thereby lowering the internal temperature and achieving the purpose of refrigeration and freezing.
The core of a cold room unit is the refrigeration unit. The unit achieves the refrigeration process by circulating refrigerant. Refrigerant is a special substance that can absorb heat by evaporating at low temperatures and then release heat by condensing at high temperatures. The refrigeration unit transfers heat by circulating the refrigerant, thus achieving the refrigeration of the cold storage.
II. Basic Components of a Refrigeration System The four main components of a refrigeration system are the compressor, condenser, expansion valve, and evaporator.
1. Refrigeration System – Compressor The compressor draws in low-temperature, low-pressure gas from the evaporator, compresses it into high-temperature, high-pressure gas, and sends it to the condenser. Common compressor types include scroll compressors, reciprocating compressors, and screw compressors.
【Scroll Compressor】
Small in size, low in noise, suitable for small cold storage facilities within 1000m³, but expensive.
[Reciprocating Compressor]
Low cost, wide range of applications, but has many vulnerable parts and high noise levels.
[Screw Compressor]
Few vulnerable parts, easy to maintain, used in large cold storage and blast freezers, high cost.
2. Refrigeration System – Condenser The refrigerant releases heat and becomes liquid in the condenser, maintaining a constant pressure equal to the compressor’s discharge pressure (high pressure). Below are the three types of condensers:
【Evaporative Condenser】
Suitable for large cold storage room
[Water-cooled condenser]
Suitable for large and medium-sized cold storage facilities in areas with water.
[Air-cooled condenser]
Suitable for small cold storage facilities in water-scarce areas
3. Refrigeration System – Condensing Unit
[Air-cooled Condensing Unit]
4. Refrigeration System – Evaporator The vapor-liquid mixture of refrigerant absorbs heat and evaporates into a gas within the evaporator, maintaining a constant pressure equal to the suction pressure (low pressure).
Defrosting Methods:
Electric Defrosting: Medium and High Temperature Cold Storage
Water Defrosting: Low Temperature Cold Storage
Hot Fluorine Defrosting: Medium and Low Temperature Cold Storage
III. Basic Components of a Cold Storage Unit A cold storage unit mainly consists of a refrigeration system, an insulated storage body, and a control panel.
1. Refrigeration System The four main components of a refrigeration system are the compressor, condenser, expansion valve, and evaporator.
2. Insulated Cold Storage Body (Double-sided Color Steel Polyurethane Sandwich Panels)
High-Temperature Cold Storage (Above 0℃): 100mm thick insulation panel ;
Medium-Low Temperature Cold Storage (-20~0℃): 150mm thick insulation panel ;
Low-Temperature Cold Storage (Below -20℃): 200mm thick insulation panel .
3. Control Box
Temperature controller (standard cold storage), PLC touch screen (standard for multi-functional cold storage, optional for standard cold storage)
Gaungxi Cooler Refrigeration Equipment Co.,Ltd.
Email：info01@coolerfreezerunit.com
Tel:008613367611012
Post time: Dec-23-2025