Refrigerated Containers: Temperature and Atmosphere Control Explained

A refrigerated container, or reefer container, has a cooling unit that makes it suitable for transporting perishable goods, which stay at a low, constant temperature throughout the journey. Here is more detail.

General features

Refrigerated containers typically carry dairy products, fruit, vegetables and meat, by land, air or sea alike. They have a refrigeration unit that connects to the power supply of a ship, an air terminal or a truck.

They are built in 20 ft and 40 ft sizes. The 20 ft has a tare weight of 3,080 kg (6,790 lb), a payload of 27,400 kg (60,400 lb), a cubic capacity of 28.3 m³ (1,000 cu ft) and an internal length of 5.44 m (17 ft 10 in).

The 40 ft has a tare weight of 4,800 kg (10,580 lb), a payload of 27,700 kg (61,070 lb), a cubic capacity of 59.3 m³ (2,094 cu ft) and an internal length of 11.56 m (37 ft 11 in).

For delivery to buyers, or when they are not in operation, they are usually moved with a truck-mounted crane.

Parts of a refrigerated container and their functions

Reefer containers are divided into five parts: the control box, the machinery (the reefer unit), the compressor, the evaporator and the condenser, which have protection and safety devices, sensors and solenoid valves to keep a constant internal temperature.

The heating and cooling systems of a refrigerated container hold the cargo at temperatures ranging from about +30 °C (86 °F) down to -30 °C (-22 °F).

Inside reefer containers the air is cooled continuously as it passes through the evaporator, which removes heat from the air circulating through the interior and keeps the products in good condition.

Operating safely

Before operating a refrigerated container it is essential to read the service manual, in order to adopt all the safety measures indicated by the manufacturer and the technical specifications of the machinery.

In addition, perishable products should be loaded as quickly as possible, while checking that the container temperature stays in line with what each specific group of goods requires.

Before loading cargo into a refrigerated container, check:

1. That it is perfectly clean.
2. That refrigeration and ventilation work perfectly.
3. That the container has already been cooled to the temperature required for each case.
4. That the thermometer is working properly.
5. That the packaged products are not damaged when placed in the container.

Special recommendation

For greater safety and functionality when transporting products that require refrigeration, it is advisable to draw a diagram of the internal dimensions of the container in question, so that whatever is being transported can be arranged optimally.

This makes better use of the space, fills the container to its maximum capacity and avoids wasting time when loading the cargo into it.

Social impact

Today the social impact of refrigerated containers is very large, since they allow consumers all over the world to enjoy fresh products all year round.

It is worth highlighting that in recent times refrigerated containers were used very frequently for the international transport of vaccines, especially during the COVID-19 pandemic.

In short, refrigerated containers are fundamental for transporting perishable products, such as food in general and medical and health supplies, so their usefulness to society is very valuable.

Learn more: Refrigerated containers

20 ft and 40 ft reefers with working cooling units. See our refrigerated containers.