Control Display
The control display is located in the unit base. It is programmed to display the current set point
associated with the control sensor located inside the air duct at the top of the case.
Minimum Run Timer Feature
The unit controller is programmed to have the condensing unit run a minimum of 5 minutes,
regardless of the control temp being satisfied. If the temperature control reaches the cut out
set point before 5 minutes, the minimum run time setting in the control will keep the unit in a
run cycle mode until the timer reaches 5 minutes. The refrigeration cycle will be off until the
temperature control cut in temperature is reached.
This timer typically comes into effect in low ambient conditions where the unit may cycle too
frequently to maintain proper product temperature.
Maximum Run Timer Feature
The unit controller is programmed to have the condensing unit run a maximum of 60 minutes.
If the unit has not reached cut out temperature setting in 60 minutes, the unit goes into on off
cycle. This typically comes into effect in high ambient temperature and relative humidity
conditions.
REFRIGERATION OPERATION
Self-Contained Models
Refrigeration R404A Charge Prior To 01/01/2020
See Refrigeration
And Electrical Data
Pages
Refrigeration R449a Charge After 01/01/2020
See Refrigeration
And Electrical Data
Pages
The self-contained models are shipped from the factory with a completely operational 404A
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 the Electronic control outlined in the control section of
this manual.
Note: The condenser fan is factory wired to run continuously.
Dual Pressure Control
(Self-Contained Models Only)
The dual pressure control is used as a safety device and is factory set. The pressure
control works on a differential. The low-pressure side is a safety to protect the
compressor in the case of refrigerant loss. The high-pressure side is a safety to protect
from system failure causing too high of system pressure.
The high side of the pressure control is factory set to 400psi and is not adjustable.
Low side setting for the R404a cases are set at 40psi differential for the cutout and
60psi for the cut-in.
Refrigerated Self-Serve Merchandiser (High Profile)
Page 13
