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IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
This manual contains important safety instructions that should be followed during the installation
and maintenance of the Liebert DS
™
. Read this manual thoroughly before attempting to install or
operate this unit.
Only qualified personnel should move, install or service this equipment.
Adhere to all warnings, cautions and installation, operating and safety instructions on the unit and in
this manual. Follow all operating and user instructions.
!
WARNING
Risk of electric shock. Can cause injury or death.
Disconnect local and remote power supplies before working within.
Before proceeding with installation, read all instructions, verify that all the parts are included
and check the nameplate to be sure the voltage matches available utility power.
The iCOM microprocessor does not isolate power from the unit, even in the “unit off” mode.
Some internal components require and receive power even during the “unit off” mode of iCOM
control.
The factory-supplied optional disconnect switch is inside the unit. The line side of this switch
contains live high-voltage.
The only way to ensure that there is NO voltage inside the unit is to install and open a remote
disconnect switch. Refer to unit electrical schematic.
Follow all local codes.
!
WARNING
Risk of explosive discharge from high-pressure refrigerant. Can cause injury or death.
This unit contains fluids and gases under high pressure. Relieve pressure before working with
piping.
!
WARNING
Risk of refrigerant system rupture or explosion from overpressurization. Can cause
equipment damage, injury or death.
If a pressure relief device is not provided with the condenser unit, the system installer must
provide and install a discharge pressure relief valve rated for a maximum of 500 psig (34bar)
in the high side refrigerant circuit. Do not install a shutoff valve between the compressor and
the field installed relief valve.
One or more additional pressure relief valves are required downstream of any and all field-
installed isolation valves as shown in Figures 57 and 58. Do not isolate any refrigerant
circuits from overpressurization protection.
For systems requiring EU CE compliance (50Hz), the pressure relief valve must be CE
certified to the EU Pressure Equipment Directive by an EU “Notified Body.”
NOTE
A pressure relief valve is provided with Liebert Lee-Temp
™
condensers. A fusible plug is
provided on Liebert Fan Speed Control condensers. The Liebert indoor cooling unit has a
factory-installed high pressure safety switch in the high side refrigerant circuit.