Vertiv Liebert DSE, System Design And User Manual

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• On 460-V, 60-Hz units, the condensate pump is rated for approximately 390 gph at 30 ft
(1476 l/hr at 762 kPa) total head.
• On 415-V, 50-Hz units, the condensate pump is rated for approximately 390 gph at 15 ft
(1476 l/hr at 381 kPa) total head.
8.2 Refrigerant Piping and Charging
WARNING! Risk of over-pressurization of the refrigeration system. Can cause explosive
discharge of high-pressure refrigerant, loss of refrigerant, environmental pollution, equipment
damage, injury, or death. This unit contains fluids and gases under high pressure. Use extreme
caution when charging the refrigerant system. Do not pressurize the system higher than the
design pressure marked on the unit's nameplate. For systems requiring EU CE compliance
(50 Hz), the system installer must provide and install a pressure relief valve in the high side
refrigerant circuit that is rated same as the refrigerant high side “Max Allowable Pressure”
rating that is marked on the unit serial tag. Do not install a shutoff valve between the
compressor and the field installed relief valve. The pressure relief valve must be CE-certified to
the EU Pressure Equipment Directive by an EU “Notified Body.”
CAUTION: Risk of excessive refrigerant line pressure. Can cause tubing and component
rupture resulting in equipment damage and personal injury. Do not close off the refrigerant-line
isolation valve for repairs unless a pressure-relief valve is field- installed in the line between the
isolation valve and the check valve. The pressure-relief valve must be rated 5% to 10% higher
than the system-design pressure. An increase in ambient temperature can cause the pressure
of the isolated refrigerant to rise and exceed the system-design pressure rating (marked on the
unit nameplate).
Consult local building and plumbing codes for installation requirements of additional pressure-relief
devices when isolation valves are field installed. Do not isolate any refrigerant circuits from over-
pressurization protection.
NOTICE
Risk of oil contamination with water. Can cause equipment damage.
Liebert® DSE systems require the use of POE (polyolester) oil. POE oil absorbs water at a much
faster rate when exposed to air than previously used oils. Because water is the enemy of a
reliable refrigeration system, extreme care must be used when opening systems during
installation or service. If water is absorbed into the POE oil, it will not be easily removed and will
not be removed through the normal evacuation process. If the oil is too wet, it may require an oil
change. POE oils also have a property that makes them act as a solvent in a refrigeration
system. Maintaining system cleanliness is extremely important because the oil will tend to
bring any foreign matter back to the compressor.
NOTICE
Risk of improper refrigerant charging. Can cause equipment damage.
Refrigerant charge must be weighed into air-cooled compressorized systems before they are
started. Starting digital scroll compressors without proper refrigerant charging can cause the
compressors to operate at less than 5°F (–15°C) evaporator temperature and at less than
52 psig (358 kPa). Operation for extended periods at less than 52 psig (358 kPa) can cause
premature compressor failure.
8 Piping and Refrigerant Requirements 39