After Start Inspection

Thermostat. Dial the thermostat setting above and below the box temperature to check thermostat operation (see Operating Modes).

Pre-Cooling. With the thermostat set at the desired temperature, allow the unit to run for one-half to one hour (longer if possible) before loading the truck. Pre-cooling will remove residual body heat and moisture from the box interior and provide a good test of the cooling system.

Defrost. When the unit has finished pre-cooling the truck interior, the evaporator temperature should have dropped below 35.6°F (2°C); initiate a manual defrost cycle. The defrost cycle should stop automatically.