16 • Refrigeration
REfRIgERATION
Off-Cycle Defrost
Periodic defrosting is necessary to keep the evaporator coil free of frost.
for defrost settings.
During off-cycle defrost, refrigerant is stopped either by stopping the compressor or by closing the liquid line solenoid valve and allowing the
compressor to pump down. The fans and lights remain on during off-cycle defrost.
If temperature termination is selected, set the termination temperature for 45°F for discharge air and coil temperature.
Note: Opening the
doors, stocking product, or shopping during off-cycle defrost may cause premature defrost termination.
Case Thermometer
An NSF thermometer is shipped loose and should be installed in the warmest product location as required by NSF. Specific field installation
instructions are packaged with the NSF thermometer.
SETTING
ORMC83D
ORMC88D
Evap Temp
28°F
28°F
Condensing Unit Cut-In
74 psig
74 psig
Condensing Unit Cut-Out
62 psig
62 psig
Return Air Temperature Cut-In
37°F
37°F
Return Air Temperature Cut-Out
33°F
33°F
Discharge Air Temperature Cut-In
34°F
34°F
Discharge Air Temperature Cut-Out
30°F
30°F
Superheat Setting *
8°F
8°F
Note: For high-glide refrigerants, use dew point for unit sizing. Adjust evaporator
pressure as needed to maintain discharge air temperatures. To receive the full
benefit of high-glide refrigerant properties, the superheat may need to be lowered
to 4-6°F. Contact Zero Zone with questions.
FIGURE 22: Case Temperature Internal Control Options (R-404A)
SETTING
ORMC83D
ORMC88D
Defrost Type
Off-Cycle
Off-Cycle
Frequency
2 Per Day
2 Per Day
Duration
30 Minutes
30 Minutes
FIGURE 23: Defrost Settings
