Fan Speed Control System; Air Cooled Systems; Charging - Data Aire gForce Ultra User Manual

5.2.3 Fan Speed Control System

The standard air cooled condenser provided with Data Aire gForce Ultra equipment has
modulating Fan Speed Control (FSC) on the all motors. The modulation speed of the
fans is directly proportional to the compressor head pressure.

Air Cooled Systems

5.3

5.3.1 Charging

5.3.1.1 Constant Speed Compressor
NOTE:
removal procedure must have been carried out. Refer to Section 2.10 Leak
Testing and Section 2.11 Evacuation prior to charging the system.
After field refrigerant piping is properly evacuated connect the refrigerant drum to the
high side and charge with liquid. Make sure all hoses are properly purged. Systems
with R-410A require approximately 3.0 lbs. per nominal ton. The compressor power
must be off and prevented from starting inadvertently/automatically. From a vacuum,
slowly open the service valve to 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. It is likely that more refrigerant will be required to complete
the charging procedure.
WARNING:
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.
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 unusual at this point.
required to complete the charging procedure.
Adjust the refrigerant charge to the sub-cooling value shown in the table below and the
sight glass has sparse bubbles. The unit should be allowed to stabilize for 15 to 20
minutes before meaningful measurements can be taken. After the system is allowed to
stabilize, verification of a few key measurements should be noted. A properly charged
system operating at typical parameters will have the following pressures:
34 ● gForce Ultra User Manual
Prior to refrigerant charging, a system vacuum and moisture
Before starting a compressor, the crankcase heater should be
If the system is charged from a vacuum, the
It is likely that more refrigerant will be
10-2014