User's Manual

Piping and Filling with Refrigerant: R-134a and R-407C Circuits

2.7 Filling the Direct Expansion (DX) Circuit—R-407C

Any recommended volumes will be approximate. The user must verify that all circuits of the system

have been adequately filled.

For Air-Cooled Liebert Lee-Temp / Flood Back Head Pressure Control Units Only

1. Make sure the Liebert XDC is Off.

2. Connect the refrigerant gauge charging hose to the refrigerant drum and to the receiver at the

rotalock valve and/or to the Schrader valves on the liquid lines.

3. Weigh in the calculated charge based on Tables 15, 16, 17 and 18—values are maximum, based

on outdoor air temperature of -30°F (-34°C).

4. Open the rotalock valve and fill the complete calculated charge.

NOTE

If necessary, refer to 3.0 - Installation Checklist to ensure that the system has been properly

checked out and is ready to be filled with refrigerant.

NOTE

Proper safety equipment and proper refrigeration tools are required. Check unit nameplate for

correct refrigerant type before topping off or recharging a system.

NOTE

Refrigerant R-407C is a blend of three components, and must be introduced and charged from

the cylinder only as a liquid.

Refrigerant R-407C uses a POE (polyolester) lubricant. Do not open the compressor unit piping

to the atmosphere for more than 15 minutes. The compressors contain POE oil that is very

hygroscopic; it quickly absorbs water from the atmosphere. The longer the compressor piping is

left open to the atmosphere, the harder it will be to fully evacuate. If left open too long, the POE

oil may need to be replaced before achieving the required vacuum level.

Table 15 Indoor unit refrigerant charge—R-407C

Model 50/60 Hz Charge/Circuit, lb. (kg)

Liebert XDC160 17.5 (8.0)

Table 16 Outdoor air condenser charge—R-407C

Outdoor Ambient, °F (°C Model 50/60 Hz Receiver Part # Charge / Circuit, lb (kg)

-30 to 100 (-34 to 38) DCSL415 185010G2/G4 200 (91)

-30 to 105 (-34 to 41) DCSL616 179713G1/G2 254 (115)

35 to 105 (2 to 41) DCSL616 181610G2/G4 164 (75)

Table 17 Air-cooled systems - liquid line charge - R-407C refrigerant per 100 ft (30 m) of Type

ACR copper tube

O.D., inches Liquid Line, lb (kg) Hot Gas Line, lb (kg)

3/8 3.7 (1.7) -

1/2 6.9 (3.1) -

5/8 11.0 (5.0 2.2 (1.0)

3/4 15.7 (7.1) 3.1 (1.4)

7/8 23.0 (10.4) 4.5 (2.0)

1-1/8 39.3 (17.8) 7.8 (3.5)

1-3/8 59.8 (27.1 11.8 (5.4)

1-5/8 - 16.7 (7.6)

Table 18 Indoor water/glycol-cooled module – R-407C refrigerant charge

Model 60 Hz Charge / Circuit, lb (kg)

Liebert XDC 160 30.0 (13.2) per circuit