20ft Reefer Container Guide: Dimensions, Temperature & Cold Chain Specs

When your cargo can spoil, rot, or degrade, a standard steel box isn't enough. You need precise climate control. Enter the 20ft Reefer Container.

Listed in the TraceContainer.com system as "20 Reefer", this is the backbone of the global "Cold Chain." From South American bananas to German pharmaceuticals, the 20ft Reefer ensures goods arrive in the exact same condition they left the factory.

This guide covers the technical specifications, loading rules, and temperature capabilities of these advanced units.

What is a Reefer Container?

A Reefer (short for Refrigerated Container) is essentially a mobile refrigerator. Unlike a dry container, a Reefer has:

1. Thermal Insulation: The walls are made of "sandwich panels" (polyurethane foam between steel/aluminum sheets) to keep heat out.

2. Cooling Unit: A machinery unit on the front wall that controls temperature, humidity, and ventilation.

3. T-Bar Flooring: The floor is made of aluminum T-shaped rails to allow cold air to circulate under the cargo.

Temperature Capabilities

Modern 20ft Reefers are incredibly powerful. They don't just keep things "cool"; they can freeze or warm cargo to precise degrees.

• Standard Range: -30°C to +30°C (-22°F to +86°F).

• Super Freezers: specialized units can go as low as -60°C for sashimi-grade tuna.

• Control: They monitor Temperature, Humidity (crucial for fruit), and Ventilation (removing CO2/Ethylene).

Dimensions: Smaller Than You Think

Crucial Logistics Note: Because of the thick insulation and the cooling machinery inside, the internal space of a Reefer is smaller than a Standard Dry container. You lose about 5-6 cubic meters of space.

Loading a Reefer: The "Red Line" Rule

Loading a reefer requires strict discipline to ensure airflow:

1. Don't Block the Air: Cold air is pumped from the bottom and flows up. Do not cover the floor completely with flat material (use pallets).

2. The Red Line: Inside every reefer, there is a red line painted near the ceiling. Never stack cargo above this line. If you do, you block the return air flow, the machinery will short-cycle, and your cargo may spoil.

Powering the Reefer

Reefers need electricity.

• On the Ship: They plug into the vessel's power grid.

• On the Truck: They require a "Genset" (Generator Set)—either a Clip-on unit (attaches to the container) or an Underslung unit (attached to the truck chassis) to keep running during road transport.

Track Your Reefer Shipment

In cold chain logistics, time is the enemy. A delayed container can mean a total loss of product. Use TraceContainer.com to keep a close watch on your refrigerated shipments to ensure they are moving on schedule.

Track my reefer container