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REFRIGERATION
Self Contained Models Use pressure gauges to set pressure control.
MODEL
CHARGE
REFRIGERATION
ITR3626 & ITR3634
18 OZ
1/2HP 3021 BTUH@90F/20F
ITR4826 & ITR4834
20 OZ
1/2HP 3750 BTUH@90F/20F
ITR6026 & ITR6034
24 OZ
1/2HP 3750 BTUH@90F/20F
The self-contained models are shipped from the factory with a completely operational 134A refrigeration
system and require no modifications or adjustments upon installation. Case must be installed as per the
installation section of this manual to provide proper condensing air cooling.
Self Contained Refrigeration Operation
The unit temperature is controlled by an electronic control that senses air temperature and turns
refrigeration on off as required to maintain proper temperature.
The electronic control will also sense a frosted coil that requires a shutdown defrost cycle and shuts down
refrigeration until defrost is complete. There are may also a defined number of daily defrosts that will also
shut the refrigeration solenoid to insure a full defrost occurs. The solenoid will remain off until the either
the off time is reached or until the electronic control senses low temperature set point
Remote Models
MODEL
REFRIGERANT
REFRIGERATION
PRESSURE CUT
IN
PRESSURE CUT 0UT
ITR3626R & ITR3634R
R134A
1/2HP 3021 BTUH@90F/20F
32#
0 #
ITR4826R & ITR4834R
R134A
1/2HP 3750 BTUH@90F/20F
32#
0 #
ITR6026R & ITR6034R
R134A
1/2HP 3750 BTUH@90F/20F
32#
0 #
Use pressure gauges to set pressure control
Remote Refrigeration Operation
The remote models are designed to use134A refrigerant and shipped from the factory with the evaporator
coil, expansion valve, drier filter, sight glass and refrigerant solenoid valve. The required high-low-pressure
control and remote condenser can be provided as a factory option and will be required to be charged with
134a refrigerant after installation.
The unit temperature is controlled by an electronic control that senses air temperature and opens and closes
the refrigerant solenoid valve as required to maintain proper temperature.
Once proper temperature is reached the solenoid valve closes and shuts off the refrigeration flow to the unit
and initiates a pump down cycle. This will allow the remote low pressure switch to open and shut off
remote compressor. The solenoid will remain off until the either the off time is reached or until the
electronic control senses that low temperature set point has been reached.
The electronic control will also sense a frosted coil that requires a shutdown defrost cycle and closes
solenoid until defrost is complete. There are may also a defined number of daily defrosts that will also shut
the refrigeration solenoid to insure a full defrost occurs. The solenoid will remain off until the either the off
time is reached or until the electronic control senses low temperature set point.
