Vertiv Liebert DSE, System Design And User Manual

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12.3.2 Condensate Pump
WARNING! Risk of electric shock. Can cause injury or death. Open all local and remote electric
power-supply disconnect switches and verify that power is Off with a voltmeter before working
within the condensate pump electrical connection enclosure. The Liebert® iCOM™ 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 the Liebert® iCOM.
To maintain the condensate pump:
1. Disconnect power to the unit using the disconnect switch.
2. Check for and clear obstructions in gravity lines leading to the condensate pump.
3. Remove the sump, clean with a stiff nylon brush and flush with water.
4. Inspect and clear clogs in the discharge check valve and float mechanism.
5. Reassemble and check for leaks.
12.4 Electronic Expansion Valve (EEV) Maintenance
The EEV controls superheat through the Liebert® iCOM™ controls by actively measuring suction
pressure via a transducer attached to the suction-line rotalock and suction temperature via a thermister
strapped to the suction line. The EEV actively adjusts the orifice size and resulting mass flow of refrigerant
to maintain the superheat setpoint (set in Liebert® iCOM). The EEV is used in place of the standard
thermal expansion valve (TXV).
WARNING! Risk of electric shock. Can cause serious injury or death. The Liebert® 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 the Liebert® iCOM
control. Open all local and remote electric power disconnect switches and verify with a
voltmeter that power is Off before working on any component of the system.
NOTE: Intermittent loss of subcooling may result in EEV/superheat instability. If superheat instability is
observed, check for proper refrigerant level in receiver (see Refrigerant Piping Guidelines
for Air-cooled Systems on page 40 for the proper charge level). If proper charge is observed in receiver,
and superheat remains unstable, then increase superheat setting in the Liebert® iCOM to 15°F (8.49°C).
12.5 Compressor Maintenance
12.5.1 Compressor Oil
NOTICE
Risk of improper compressor lubrication. Can cause compressor and refrigerant system
damage.
Failure to use oil types, viscosities and quantities recommended by the compressor
manufacturer may reduce compressor life and void the compressor warranty.
• Do not mix polyolester (POE) and mineral-based oils.
• Do not mix oils of different viscosities.
• Consult Vertiv technical support or the compressor manufacturer if questions arise.
Compressor Type Oil Type
Copeland Scroll and Digital Scroll POE Oil - ISO 32 Centistoke Viscosity
1
1. Use Copeland POE Oil ULTRA 32-3MAF or other Copeland-approved oils.
Source: DPN003950. Rev.5
Table 12.2 Compressor oil types for R-410A Refrigerant
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