Remember that refrigerant is always under pressure in the entire system. Escaping
refrigerant often results in frostbite. Only those trained in refrigerant system work, familiar with proper service procedures and equipped with special gauges and connectors should ever attempt to open up the service valves or other fittings and charge or discharge the system.
The high pressure lines, compressor surfaces, condenser and related parts will be hot unless the unit has been shut down for some time. Always avoid touching them unless you know the unit has had plenty of time to cool.
Getting Ready for Pickup
Knowing how to properly operate your reefer unit is an important part of the job. First you must find out the required temperature for each load from the shipper, your broker or dispatcher. For example, ice cream is kept at -20 degrees F. Other frozen foods may be kept at about 0 degrees or +10 degrees F. Fresh vegetables are often kept at 35 degrees F.
But switching on the reefer unit when you pick up your load is not enough, Naylis says. Turn the unit on and set the temperature an hour or more before you pick up the load. The box has to be at the set point before you load it.
When the pre-trip has been run, press any key. The temperature set point will then be displayed on the left side of the message center of the controller display. To change the temperature set point, once it is displayed, press the up or down arrows. Once you have brought the set point to the temperature needed for the load, press the = button to set it in the memory and activate it.
The unit normally runs in the start-stop mode. This is the normal mode for frozen food. You’ll see “START STOP MODE SELECTED” in the lower message center and the start-stop light at the top of the controller display will be lit when this mode is selected.
Fresh vegetables and some other cargoes require that the air be circulated constantly to keep humidity from accumulating on the product. In stop-start mode, the engine shuts down as soon as the set temperature is reached, and this stops the fans. However, in continuous mode, the engine will continue to run, and the temperature will be kept at the set point by varying the compressor’s capacity via the cylinder unloaders and suction throttling valve. To set the unit for continuous run, press the START-STOP/CONTINUOUS key until the CONTINUOUS RUN light at the top of the display illuminates, and “CONTINUOUS RUN MODE SELECTED” appears in the lower liquid crystal display.
For further information, please contact the following:
Thermo King Corp.