Data Aire gForce DX series - System Evacuation; Air Cooled System Charging

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If an optional remote heat exchanger (DARC) (air cooled or dry coolers) is ordered it can be either single
or three phase, but the individual Permanent-Split Capacitor PSC fan motors are single phase and will
only run in one direction. Check the operation of the fans by placing a momentary jumper across the low
voltage eld terminals. On most remote heat exchangers the terminals will be #39 and #40. Check the
wiring diagram for the terminal numbers to jumper across. This will energize the control circuit.
NOTE: Disconnect pumps on glycol systems unless already lled with water/glycol
solution.
The remote heat exchanger fans may not run because the evaporator section has not reached the
required head pressure or the thermostat set-point is above the current ambient or water temperature.
Please see the Air Cooled Condenser or Fluid Cooler User Manuals for more detailed information
regarding the remote heat exchangers.
5.2 Evacuation
It is of the utmost importance that proper system evacuation and leak detection procedures be employed.
Good evacuation processes include frequent vacuum pump oil changes and large diameter, short
hose connections to both high and low sides of the system preferably using copper tubing or bronze
braided hose. A deep vacuum gauge capable of registering pressure in microns should be attached
to the system for pressure readings. A shut-o󰀨 valve between the gauge connection and vacuum
pump should be provided to allow the system pressure to be checked after evacuation. Do not turn o󰀨
vacuum pump when connected to an evacuated system before closing shut-o󰀨 valve.
Evacuate the refrigerant lines, condenser coil and evaporator coil to 500 microns or lower (a micron
gauge and 2-stage vacuum pump are required). Valve o󰀨 and turn o󰀨 the vacuum pump and wait at
least 15 minutes to make sure the micron gauge reading does not go back above 750 microns. If it
does, restart the vacuum pump and evacuate until the system reaches 500 microns. If the system still
does not hold the pressure below 750 microns the system needs to be rechecked for leaks.
WARNING: Do not apply power to the compressor when in a vacuum.
5.3 Air Cooled Systems
5.3.1 Fan Speed Control System Charging
Air cooled condensers provided with Data Aire equipment have integral fan speed controls. The fan
speed control is programmed at the factory to start the fan at a specic head pressure and increase
speed (i.e., airow) when the su󰀩cient head pressure is developed, the fan will run at full speed. The
programming of this fan speed control is based on the refrigerant required by the order. Please see the
Air-Cooled Condenser User Manual for more detailed information on fan speed control.
NOTE: Refer to Section 2.10 Leak Testing and Section 5.2 Evacuation prior to charging
the system.