Data Aire gForce Ultra, Installation, Operation & Maintenance Manual

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gForce Ultra IOM
51
refrigerant. A liquid charging adapter prevents liquid refrigerant from entering the
compressor.
•
In some cases, the assistance of a refrigerant recovery machine may be necessary to add
the initial charge.
•
Care must be taken to prevent from over charging the system and from liquid entering the
compressor and diluting the oil.
•
The return air temperature to the unit being charged must be stable and must be maintained
greater than 65°F (18°C). If this is not possible due to lack of heat load, then load banks must
be used to offset the cooling load during startup.
•
Start the unit up by using the setpoint under Menu B
– Setpoints
•
When charging, if the ambient is less than 60

F (15.6

C) , some refrigerant will be backed
up in the condenser coil, causing the liquid level to drop. If head pressure is below 320 PSIG
(2206 kPa) , block the condenser coil surface, or turn OFF the fans until pressures rises
above 380 PSIG (2620 kPa) , while observing the receiver sight glass.
•
Do not obtain final refrigerant reading when the variable speed compressor is running at low
speed.
•
Heat load is required when adjusting charge, use load banks to offset the cooling load.
•
Suction pressure should be equal to 33

F (0.56

C) saturated temperature or greater
•
When the system is properly charged the EEV valve should be between 55% and 85% with
an indoor temperature of 70°F (21.1

C) to 74°F (23.3

C).
•
See further instructions for the following options:
Section 5.7.2 Air-cooled System Charging
Section 5.7.8 Flooded System Charging (Systems with Low Ambient Receiver Package)
Section 5.7.9.7 Water/Glycol-Cooled System Charging
Voltage Phase Check
Evaporator Phase Check
Prior to fully charging a unit, the correct voltage phasing should be checked on the indoor evaporator.
EC plug fans are not dependent on the input power phasing and will always operate in the proper
direction.
Before checking the fixed speed, scroll compressor voltage phasing make sure that its circuit has been
charged with 80% of its refrigerant capacity by following the steps in Section
5.7.3 Pre-Charge Fixed
Speed Compressor or 5.7.6 Pre-Charge Variable Speed Compressor for initial charging.
Replace the fuses for each compressor (one at a time for dual circuit units) which were removed in the
above WARNING.