Aug 17, 2018

Control your spending during the hot weather months by taking some preventative measures that can decrease the number of service calls on your units.  Pre-cooling and proper temperature settings when loading can keep the heat out of your trailers and wallets.  PLM recommends the following tips for pre-cooling your trailer during the hot weather :

Pre-Cooling:

• PLM trailers should be pre-cooled for at least 30 minutes before loading of any product. 
• For multi-temp trailers- Only Zone 1 should be used when pre-cooling the trailers. All other zones should be off during the pre-cool process and any bulkheads need to be placed to the side of the trailer. 
• To pre-cool the trailer, set the unit temperature set point to 10 degrees below the desired set point of the product being loaded into the trailer. 
• Caution- setting unit set point too far below or above  product temperature could cause product to be damaged.

 
Prior to Loading

• Make sure product being loaded into trailer is pre-cooled to desired temperature prior to loading. 
• Reefer units are designed to maintain temperature in the compartment and are not designed to pull product temperature down to a specific temperature over time. 

Loading warm product into a trailer will cause the unit to cycle into defrost too frequently and product loss could result.
 

• Pre-cool trailer to 10 degrees below the desired set point of the product being loaded in to the trailer. 
• DO NOT load trailer before unit has reached set point.  This is to ensure unit can perform as needed and interior of trailer is colder than the product being loaded.
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• All product loaded into any refrigerated trailer needs to have proper air flow around it to keep it cool/cold.  
• Keep all product 2-4 inches from trailer walls and bulkheads and between palletized product.
• If loading palletized product onto a flat floor (non-ducted) trailer it is important to note that the pallet is the path for return air to flow back to the reefer unit and this path needs to be unrestricted by the pallet orientation. 

Loading the Trailer

• Zone 1

        - Turn reefer unit and all zones off just prior to loading zone 1.
         - Single temperature load or Zone 1 for multi-temperature trailers.
         - Install bulkhead and/or close trailer doors for single temp trailer. Turn reefer unit zone 1 on and change set point for zone 1 to the desired set point of the product being loaded in to the trailer.
         - If multi-temp trailer Zones 2 and 3 (if equipped) are to remain off

• Load Zone 2

         - Install bulkhead Turn reefer unit zone 2 on and change set point for zone 2 to the desired set point of the product being loaded in to the trailer. Zone 3(if equipped) is to remain off.

• Load Zone 3

         - Install bulkhead if required and/or close trailer doors.  Turn reefer unit zone 3 on and change set point for zone 3 to the desired set point of the product being loaded in to the trailer. Once trailer is loaded check and verify all zone set points and defrost intervals are properly set.