Piping and Filling with Refrigerant: R-134a and R-407c Circuits
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2.5 Filling the Pumped Circuit—R-134a
1. Connect a charging manifold to the service port of the receiver outlet valve.
2. Purge the hoses.
3. Calculate the amount of R-134a refrigerant needed to charge the system, using the values in
Tables 6,7,8 and 9; for assistance, refer to 2.5.1 - Calculating Refrigerant Charge—
Example. The section includes a worksheet to calculate system refrigerant charge requirements.
4. Weigh in the calculated charge.
5. After adding the calculated charge, allow the system to sit 15 to 30 minutes to reach equilibrium.
Observe the refrigerant level through the sight glasses of the receiver. The level should be above
the second sight glass at a minimum when the Liebert XDC is off.
6. If the refrigerant level is improper, the charge must be adjusted.
If the level is too high or too low, recalculate the required charge and reduce or increase the
amount as needed to reach the proper level.
NOTE
All lengths in Tables 7,8 and 9 are actual pipe lengths, not equivalent pipe lengths.
NOTE
System refrigerant volume calculations derived from Tables 6,7,8 and 9 are based on a fully
loaded system. Additional charge may be required for lightly loaded systems.
Table 6 System R-134a charge for a Liebert XDC with any model Liebert XDH/Liebert
XDO/Liebert XDV/Liebert XDCF
Refrigerant Charge,
lb (kg)
Per Liebert XD Unit
(Excludes Connector Lines
to and from Liebert XD Cooling Module)
157 lb. (65.7kg) Liebert XDC
3.55 lb. (0.66kg) Liebert XDO
2.32 lb. (1.05kg) Liebert XDV
5.32 lb. (2.41kg) Liebert XDH
1.41 lb. (0.64kg) Liebert XDCF
Table 7 System refrigerant charge for the supply and return mains
Refrigerant Charge,
lb/foot (kg/m) Supply/Return Main Length and Diameter
0.45 (0.67) Main supply actual length per 1-1/8" OD copper tubing
0.68 (1.01) Main supply actual length per 1-3/8" OD copper tubing
0.28 (0.42) Main return actual length per 2-1/8" OD copper tubing
0.43 (0.64) Main return actual length per 2-5/8" OD copper tubing
Table 8 R-134a refrigerant charge for hard-piped connector lines to and from any model
Liebert XDH/Liebert XDO/Liebert XDV/Liebert XDCF
Refrigerant Charge,
lb/foot (kg/m) Hard-Piped Connector Length and Diameter
0.08 (0.12) 1/2" OD Liebert XDO/Liebert XDH/Liebert XDV/Liebert XDCF supply connector actual length
0.13 (0.19) 5/8" OD copper tubing Liebert XDV/Liebert XDCF supply connector actual length
0.26 (0.39) 7/8" OD Liebert XDO/Liebert XDH supply connector actual length
0.02 (0.03) 5/8" OD copper tubing Liebert XDV/Liebert XDCF return connector actual length
0.04 (0.06) 7/8" OD copper tubing Liebert XDV/Liebert XDCF return connector actual length
0.04 (0.06) 7/8" OD copper tubing Liebert XDH/Liebert XDO return connector actual length
0.07 (0.1) 1-1/8" OD copper tubing Liebert XDH/L iebert XDO return connector actual length