All Cooler Models
Cooler Defrost Control
Cooler units utilize an electronic temperature control. The temperature may be adjusted by setting the dial. This control is preset to provide 3 hours of compressor run time between defrost cycles. Defrosts are temperature terminated and cannot be reprogrammed. The temperature control
is programmed for minimum on cycle of one minute and minimum off cycle of four minutes.
Maintenance
The evaporator section of a 
system should be checked at least once for proper defrosting because the amount and pattern of frosting can vary greatly. The frost
Air Defrost Sequence of Operation for Coolers
Air defrost units are preprogrammed for 3 hours of compressor run time between defrosts. These periods are not reprogrammable. After 3 hours, the temperature control will turn the compressor off. When the coil temperature reaches 38°F, the control will terminate the defrost cycle.
Room Thermostat Settings:
• Approximate dial settings of control
0 = Unit off (not an electrical disconnect)
1 = 52°F (11°C)
2 = 49°F (9°C)
3 = 45°F (7°C)
4 = 41°F (5°C)
5 = 38°F (3°C)
6 = 34°F (1°C)
NOTE: If power is interrupted to the unit during the refrigeration
System Standard Maintenance Guidelines
After first year of operation and under normal usage, maintenance should cover the following items at least once every six months:
1.Check and Tighten ALL electrical connections.
2.Check all wiring and insulators.
3.Check contactors for proper operation and for worn contact points.
4.Check all fan motors. Tighten motor mount bolts/nuts and tighten fan set screws.
5.Clean the condenser coil surface.
6.Check the operation of the control system. Make certain all safety controls are operating properly.
7.Check that all defrost controls are functioning properly.
8.Clean the evaporator coil surface.
9.Clean the drain pan and check the drain pan and drain line for proper drainage.
3. Coolers
11