Operating in the produce transportation industry means that we must have expert knowledge in refrigerated trailer temperature settings, to ensure that product arriving at receivers is in optimal condition.

There are two types of refrigerated trailer temperature settings: continuous & cycle-sentry. The produce industry requires that continuous setting MUST be used when transporting fruits and vegetables. These products need continuous air flow to handle the heat of product respiration and continuous air flow allows for more consistent temperature throughout the trailer for the duration of transport. All reefer units have a ‘Set Point’; this is the setting that the driver must manually set the refrigerated trailer to run at, as per the BOL/Customer’s requested running temperature. For example, if you have a set point of 33°F Continuous, the temperature reading displayed by the set-point will stay constant on a smart reefer download.

On continuous setting, the refrigerated trailer unit does have a set defrost cycle (defrost cycle is the process of removing ice or frost buildup from a coil). The intervals are factory set for every 6 hours, but the unit will auto defrost based on a temperature difference across the coil. The defrost cycle can be changed to compensate for produce that has higher heat respiration, for higher ambient temperature (ambient temperature is the certain temperature within an enclosed space), and for door openings. For example, if it is a humid day and the driver is doing a lot of door openings, you may need to have a more frequent number of defrost cycles. Although the reefer has this defrost cycle on continuous setting, it does not change the product temperature due to the fact that most reefers have a very high heating capacity (heating capacity is the amount of heat energy needed to raise the temperature of a given mass of a substance by one degree Celsius). The temperature in the air of the reefer will heat at a faster rate than the temperature of the product that is in the trailer. The time of a defrost cycle is not is significant enough to affect the product temperature.

Below is an example of a temperature recorder printout for a reefer in continuous mode (note spike at end of 41°F is at unloading point):



Running your refrigerated trailer unit on continuous is an industry requirement, and running a load on cycle-sentry will greatly increase your exposure to claims or additional charges due to product damage.

Need some assistance with this or any other information? Our Carrier Relations Department are the experts with this type of information, and more! They can assist in advising on loading particulars, along with managing finances, regulatory requirements, and administering paperwork. And remember, ALL our carrier partners can send us their paperwork using TRANSFLO Express Truckstop Scanning! The cost is better than many of our competitors at $1 per transmittal, which is deducted from your final load settlement and helps to share the cost of this great service. TRANSFLO has also recently acquired TripPak Services, which means the network of available truckstops has expanded to approximately 1300 locations nationwide. We highly encourage all our carriers to use this service, it can save you hundreds of dollars a year!!!!

Refrigerated Trailer Temperature Settings: A Carrier Relations Review was last modified: by