By Emilly Huan    Photo：CANVA

1.Temperature Definitions for Export Refrigerated and Freezer Cabinets:

A.Chilled: 2～8℃ (fresh produce, fruits, dairy products, cooked foods, vaccines, etc.)

B.Frozen Cabinet: Below -18°C (meat, seafood, ice products, frozen foods)

The customer's order / letter of credit / packing list shall be the final standard.

2．Pre cooling standard process before container loading

A. Pre cooling purpose

• Reduce the temperature of the cabinet to the set temperature

• Avoid temperature rise, cargo damage, customer complaints, and return shipping after loading

B. Standard practice for pre cooling

•Close the container door

•Set target temperature (such as 0 ℃/-18 ℃)

•Pre cooling to stability:

Refrigeration: Stable at 2-8 ℃

Freezing: Stable below -18 ℃

•Pre cooling time: generally 30-90 minutes (depending on cabinet condition and outdoor temperature adjustment)

C. Pre cooling qualification judgment

The temperature must not rise for 5-10 minutes before loading can begin.

3.Timing and rules for plugging in (powering on)

A.When is it necessary to plug it in?

•Immediately plug in the power after picking up the cabinet

•Maintain power during loading, after loading, and during waiting at the dock

•Before boarding, the power will be cut off by the dock (taken over by the ship)

B. Attention to power on (very important)

• Do not frequently plug or unplug (compressor is prone to damage)

• Power supply: 380V three-phase power (must be correctly connected, phase loss will cause machine failure)

•When loading, the door can be opened for a short period of time without cutting off the power, but it should be closed as soon as possible

4.Temperature record (most commonly checked for export)

A. Record frequency

• Before container loading: Pre cooling completion temperature

• During container loading: every 30 minutes to 1 hour

• After container loading: stabilize the temperature after closing the door

• Dock waiting: continuous monitoring

B. Record content (suggested form)

• Container number

• Set temperature

• Actual temperature (return air/supply air)

• Date and time

• Operator

• Abnormal remarks

C. Source of temperature data

Mainly displayed on the freezer control panel,

Assisted by independent thermometer verification (often required by customers/inspectors).

5．Exception handling (most practical for export)

Exception A: Temperature cannot be lowered/consistently high

1. Check if the door is tightly closed and if the door seal is damaged

2. Check if the cargo is too full or blocking the air duct (poor air circulation)

3. Check if the power supply is stable and if there is a phase loss

4. Handling:

• Stopping loading

• Notify the shipping company/freight forwarder

• Changed the container (if necessary)

Exception B: Alarm

Common: high temperature alarm, low temperature alarm, power supply abnormality, sensor abnormality

• Take photos to record the alarm code

• Close the door and stabilize again for 15 minutes

• Still report to the police → Apply for container replacement, do not force export

Exception C: Temperature rises after loading

• Close the door immediately

• Keep the plug in operation

• Observe for 30-60 minutes to see if it falls back

• Do not fall back → handle as above (changed container)

6.Golden rule for container loading site (avoiding 90% cargo damage)

A. The goods must be pre cooled before being loaded into the container (do not expect the container to cool down the hot goods)

B. Do not block the return and supply air vents

C. The loading speed should be fast to reduce the opening time

D. The container seal is intact and undamaged

F. Confirm before closing the container: stable temperature and no alarms

Appreciate if you could share TGL Blog among your friends who are interested in first-hand market information of supply chain and updated economic incidents.