Vertiv Liebert PFD - Page 17

Item Description
14 Check valve
15 Pressure-balancing valve
16 Sight glass
17 Pressure-relief valve
18 Lee-Temp receiver
19 Receiver-heater pressure-limiting switch
20
Schrader port with valve core
NOTE: The system includes a factory-installed Schrader valve with core in the liquid line downstream of the
receiver. Proper evacuation of the condenser side of the system can be accomplished only using the downstream
Schrader valve. See the appropriate piping schematic for your system in Submittal Drawings on page35.
21 Liquid-line solenoid valve
22 Liquid line
23 Filter drier
24 Expansion valve
25 Evaporator coil
To evacuate and leak-test the system:
1. Open the liquid-line solenoid valve by removing the holding coil, and apply a solenoid-valve
service magnet to the valve.
2. Connect manifold-gauge hoses on the discharge- and suction-line Schrader ports, open the
service valves, and place a 150PSIG(1034kPa)charge of dry nitrogen with a tracer of
refrigerant, then check the system for leaks with a suitable leak detector.
3. 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.
4. 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, proceed to Charging Air-cooled Systems below.
Charging Air-cooled Systems
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 valve in the compressor suction line. 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 component re-installation. Can cause equipment damage.
Identify and mark location of the discharge pressure switch. It must be reinstalled in its original
location.
Initially charging the system:
1. Check the nameplate on the indoor unit for refrigerant type to use.
4 Piping and Refrigerant Requirements 17