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ELECTRONIC CONTROL OPERATION
This unit is equipped with an electronic temperature control. The control parameters are set at the factory
and cannot be manually changed in the field. The pre set control parameters are listed on the chart in the
Settings Chart below.
Operation
The control uses two sensors, one located in the air stream and one located on the evaporator coil.
The sensor located in the air stream is referred to as the temperature control sensor. The sensor
located on the evaporator coil is referred to as the defrost probe.
The temperature control sensor is located on the plastic tub behind the evaporator coil to the left in
the cold air stream. The sensor location is critical for proper operation on the unit. Do not move or
relocate this sensor.
The coil sensor is strapped to the evaporator coil. This sensor location is critical for proper
operation of the unit. Do not move or relocate this sensor.
The temperature control is set to cut in at 39°F (3.9°C). The Temp control cuts out at 26°F (-3.3°C)
at the coldest setting “9” and 36°F (2.2°C) at the warmest setting “1”.
See “
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for more
details on using the control.
Defrost Cycle
The control is programmed to initiate defrost via two different methods. There are 3 programmed
defrost cycles in the case which will initiate a defrost cycle every 8 hours. The unit does not have a
time clock so the defrost cycles cannot be set for any specific time of day.
The unit also has an ‘On demand’ defrost feature that will initiate a defrost when the temperature
differential between the evaporator temperature and the air temperature is more than 20°F (11.1°C)
for 5 minutes after 30 minutes into the refrigeration cycle (e.g. if the air stream probe measures
42°F/5.6°C or greater and the defrost probe measures 20°F/-6.7°C or lower for five minutes). Once
initiated the defrost cycle will terminate when evaporator coil sensor reaches 43°F (6.1°C).
If a manual defrost is required, one can be initiated by pressing and holding the down arrow for
three (3) seconds. This is typically unnecessary and should only be performed if special
circumstances require it.
