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4.0 CHARGING
4.1 Voltage Phase Check
4.1.1 Evaporator
Prior to charging, the correct voltage phasing should be checked on the indoor evaporator. Using
the manual switch operation will not bring the fans to full speed. Enabling the BLOWER manual
mode switch on manual override module engages the contactors powering the high voltage to the
plug fans but sets the control signal to 0V.
Enabling any other manual mode switch will likewise disable all control outputs from the dap4 panel
resulting in full manual mode operation and setting the plug fans to 0V.
To test the plug fan modules in manual mode, turn on the blower and fan speed on manual override
module. This will enable the fan control signal at maximum. The fans will spin at near full speed if
the contactors are enabled.
Although scroll compressors are phase dependent, units shipped from the factory are run tested,
ensuringthecompressorrotationisconsistentwithevaporatorfanmotor.However,aeldchange-
out of a compressor may require checking proper phase. An out-of-phase compressor will draw
relatively low amps and both the suction and discharge pressures will remain nearly equal.
4.1.2 Secondary Heat Exchanger
See separate Installation, Operation and Maintenance (IOM) Manual for air cooled condensers or
uidcoolersforthedetailonthesecondaryheatexchanger.
4.2 Air Cooled Systems
4.2.1 Fan Speed Control System Charging
The standard air cooled condenser provided with Data Aire gForce equipment has modulating fan
speedcontrol(FSC)ontheallmotors.Aftereldrefrigerantpipingisproperlycompletedconnect
the refrigerant drum to the low side and charge with vapor (refer to Section 2.6 LEAK TESTING and
Section 2.7 EVACUATION prior to charging the system).
It is likely the more refrigerant will be required to complete the charging procedure (line runs need
to be taken into account). Make sure all hoses are properly purged. From a vacuum feed liquid
refrigerant into the high side of the system until the pressure equalizes. At this point there will be
approximately 70-80% of the total charge in the system.
Before starting a compressor, the crankcase heater should be energized for a minimum
of 12 hours to reduce the possibility of liquid slugging on start-up. Failure to energize the
crankcase heater could result in compressor damage.
If the system is charged from a vacuum, the preheating of the compressor is not necessary. Start
the system and allow the system to stabilize to room temperature. Bubbles in the sight glass are not
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