Liebert 50 & 60Hz Manuel D’Utilisation

The condensing unit may be located above the dropped ceiling or any remote indoor area. If noise is of 

concern, the condensing unit should be located away from personnel. Normal operating sound may be 

objectionable if the condensing unit is placed near quiet work areas.
To mount the unit in the ceiling, refer to 2.4 - Installing the Evaporator or Chilled-Water Units.

Details for Refrigerant (R-22) Loop piping are in 2.4.3 - Piping Connections and Coolant 

Refer to Figure 20 for recommended field installed piping hardware such as shut-off valves and hose-

bibs. Water filters should be installed if water quality is poor. Filters will extend the service life and 

efficiency of the condensers.

The maximum fluid pressure is 150 psi standard pressure or 350 psi for high pressure units (Refer to 

unit serial tag and model number description page at beginning of this manual).

Water/Glycol-cooled units include a coolant flow regulating valve which is factory adjusted and should 

not need field adjustment.
Standard water pressure and high water pressure valves are adjusted differently. Contact Liebert 

Service before making any adjustments.

Refer to 2.4.4 - Electrical Connections, Evaporator or Chilled-Water Unit for general wiring 

requirements and cautions. Refer to electrical schematic when making connections. Refer to serial tag 

for full load amp and wire size amp ratings.

A six-wire control connection is required from the evaporator unit to the water/glycol condensing unit. 

Two (2) additional wires are required when hot gas bypass is ordered. Glycol-cooled units also