Data Aire gForce Ultra - 7. Variable Speed Compressor; 7.1 Features; 7.2 Oil Management; 7.3 Crankcase Heaters

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NOTE: Charging to a full liquid line sight glass should never be the sole
means of determining the correct refrigerant charge. Other parameters such
as superheat, suction pressure, head pressure, sub-cooling and ambient
temperature are also important. A system charged to a clear sight glass is
often overcharged.
When charging is complete, close the valve on the refrigerant manifold set and close the service valve
on the refrigerant tank. Then go back into menu “H. Calibrate Sensors” and set either the “Return Air
Temp Sensor” or “Discharge Air Temp Sensor” menu o󰀨set values back to 0. If a calibration o󰀨set value
has been determined in the eld that is di󰀨erent from 0 bring the o󰀨set number back to this value.
5.6 Water/Glycol System
5.6.1 Water/Glycol Cooled System Charging
All water/glycol cooled units are factory charged with refrigerant. The water regulating valve should
be adjusted to maintain the required conditions. Field charging, if required, of water/glycol systems
should be done by referring to the unit’s electrical nameplate. The factory charge is indicated on the
nameplate. Although this gure represents the initial factory charge, it is still necessary to measure
and note proper unit operation including superheat, head and suction pressure. Some adjustment of
charge may be required.
Adjust the refrigerant charge until the sight glass clears or has sparse bubbles. The system should
be allowed to stabilize for 15 to 20 minutes before meaningful measurements can be taken. After the
system is allowed to stabilize, verication of a few key measurements should be noted.
Function R-410A Conditions
Condensing Temperature 105 to 119⁰F (41 to 48⁰C)
Saturated Suction Temperature 33⁰F (0.6⁰C) or higher
Superheat 8 to 15⁰F (4.44 to 8.33⁰C) Di󰀨erential
The superheat at the compressor suction line at least 6 inches (152 mm) away from the compressor.
All water/glycol cooled units have a water regulating valve. A head pressure transducer is connected
to a Schrader tting on the discharge line and water is regulated into the condenser coil (plate n con-
densers are standard).
WARNING: Before starting a compressor, the crankcase heater should be
energized for a minimum of 12 hours to reduce the possibility of liquid slug-
ging on start-up. Failure to energize the crankcase heater could result in
compressor damage. If the system is charged from a vacuum, the preheat-
ing of the compressor is not necessary.