Liebert PX018 Installer's/User's Manual page 44

3. At the compressor, connect refrigerant gauges to the suction rotalock valves and discharge-
line Schrader valves.
4. Open the service valves and place a 150 PSIG (1034 kPa) charge of dry nitrogen with a tracer of
refrigerant. Check system for leaks with a suitable leak detector.
5. After completion of leak testing, release the test pressure, (observe local code) and pull an
initial deep vacuum of 500 microns on the system with a suitable pump.
6. After 4 hours, check the pressure readings and, if they have not changed, break vacuum with
dry nitrogen. Pull a second and third vacuum to 500 microns or less. Re-check the pressure
after 2 hours.
When the 3 checks are complete, remove the jumper hose from the service-valve fitting and
the condenser, and proceed to
below.
Charging Air-cooled Systems with Liebert Lee-Temp Receiver
NOTICE
Risk of improper refrigerant charging. Can cause equipment damage.
R-410A is a blended refrigerant and must be introduced and charged from the cylinder only as
a liquid.
When adding liquid refrigerant to an operating system, it may be necessary to add the
refrigerant through the compressor suction service valve.service . Care must be exercised to
avoid damage to the compressor. We recommend connecting a sight glass between the
charging hose and the compressor suction service valve. This will permit adjustment of the
cylinder hand valve so that liquid can leave the cylinder while allowing vapor to enter the
compressor.
NOTICE
Risk of improper operation. Can cause compressor failure.
Operating the unit with the EEV closed can cause compressor failure. The reheat and
humidifier are disabled. A minimum of 20 psig (138 kPa) must be established and maintained
for the compressor to operate. The charging function can be reset as many times as required
to complete
To calculate the charge for the system:
1. Check the nameplate on the indoor unit for refrigerant type to be used. Unit control
configurations differ depending on refrigerant type.
2. The unit must be operating, refer to .
3. Calculate the amount of charge for the system. See
Air-cooled Systems
4. Accurately weigh in as much of the system charge as possible before starting the unit.
Vertiv | Liebert® PDX™ and PCW™ Installer/User Guide |
Charging Air-cooled Systems with Liebert Lee-Temp Receiver
on page 36.
Refrigerant Charge Requirements for
44