Emerson Xtreme Density manual Liebert XD Refrigerant, Liebert XD Piping System Design

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Designing a Liebert XD Solution

3.12Liebert XD Refrigerant

The refrigerant used in the Liebert XD system is HFC-134a (1,1,1,2-tetrafluoroethane), made by a number of manufacturers. The amount of refrigerant used by the Liebert XD system may be signifi- cantly higher than in typical DX cooling systems.

! CAUTION

Risk of improper oil use. Can cause equipment damage.

The Liebert XD pumped R-134a refrigerant circuits do not use refrigerant oil. Do NOT put oil in the R-134a system.

All the major components of a Liebert XD system must be installed in a space with a volume of at least 1,000 ft3 (28.3m3) for each 13 pounds of refrigerant in that system from Table 1, ASHRAE Stan- dard 15-2001, Safety Standard for Refrigeration Systems. If the Liebert XDP/Liebert XDC is placed in a separate area, such as a machine room, then this area must also meet the volume requirement. Inside the critical space, this includes the space under the raised floor, and the space between the top of the raised floor and the bottom of a suspended ceiling. If the suspended ceiling is all open grates, then this additional space, up to the overhead deck, would also be included.

Example

A space is 5,000 square feet, with an 18" raised floor and an 8' 6" suspended ceiling. Liebert XDOs and a Liebert XDP are to be placed in this raised-floor area.

The volume of the space is (1.5 + 8.5) x 5,000 or 50,000 cubic feet.

The maximum amount of R-134a refrigerant that can be used in a single Liebert XDP/Liebert XDC/Liebert XD module system within this space is 16 * (50000/1000) = 16 * 50 = 800 lb.

Multiple Liebert XD systems can be installed in this space, as long as the amount of R-134a refrigerant in any one system does not exceed 800 lb.

NOTE

Local codes might permit exceeding the maximum refrigerant limit stated above if refrigerant detector and an exhaust system are installed. As an alternative, oxygen sensors may be installed to meet some local codes.

3.13Liebert XD Piping System Design

All piping must be ASTM (American Society for Testing and Materials) Type “L” copper pipe. The typ- ical maximum operating pressure in the system is 90 psi (620kPa).

Piping for the Liebert XD system is arranged in a manner similar to piping for a chilled water system. Liebert XD cooling modules (Liebert XDCF, Liebert XDH, Liebert XDO or Liebert XDV) are connected in parallel between the main return and supply pipes going to and from the Liebert XDP/Liebert XDC. Figure 23 represents a typical configuration. The guidelines provided for pipe size must be strictly followed. Failure to size the main lines and connection lines adequately may result in reduced cooling capacity. The critical aspects of pipe sizing are related to refrigerant volume and pressure drop. Each must be minimized.

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Contents Liebert Xtreme Density Page Table of Contents Specifications XDH and Liebert XdcfIii Tables Liquid Liquid/Vapor Mix CoolFrame, XDH Direct and Indirect System Configurations European Union Fluorinated Greenhouse Gas RequirementsLiebert Heat Rejection Air Cooled or Water/Glycol Cooled Pumped RefrigerantLiebert XDO-Overhead Cooling Module Liebert XDV-Vertical, Above-Cabinet Cooling Module Liebert XDH-Horizontal Cooling Module Liebert Xdcf Liebert Xdcf units on BladeFrame EX cabinetsLiebert XDA-Air Flow Enhancer Liebert XDP-Pumping Unit Liebert XDP Minimum LoadLiebert XDC-Refrigerant Chiller Liebert XDC Minimum LoadLiebert XD field-installed port kits header connection size Liebert XD PipingLiebert XD Field Piping Flexible Piping Kit Prefabricated HeadersDetermining Cooling Equipment Needs Implementing a Hot-Aisle/Cold Aisle Design Hot aisle-cold aisle arrangement with under-floor sourceDetermine Cooling Requirements and Select Liebert XD System Calculate the Heat Load to be Handled by Liebert XD SystemAirflow Requirements for Liebert XD Solutions Configuring a Liebert XD SystemSelecting Liebert XD Cooling Modules Number of Modules Supported by a Liebert XDP or Liebert XDCLiebert XDO Placement Determining Spacing of Liebert XDOs in an AisleLiebert XDO spacing-horizontal and vertical Liebert XDV is suspended From ceiling structure Liebert XDV Unit PlacementInput Information Step Results Liebert Xdcf Placement Liebert Xdcf unit mounting locationsLiebert XDH Placement Liebert XDP/Liebert XDC PlacementInterlaced piping arrangement For enhanced protectionFor enhanced Interlaced piping arrangement for enhanced protectionProtection Liebert XD Refrigerant Liebert XD Piping System DesignSupply, return pipe sizes for refrigerant loop Key to Piping Pipe Function Size / Equivalent Pipe LengthLiebert XD Piping Slope Bypass Flow ControllersRefrigerant Pumped XD CoolFrame, XDH, XDO or XDVLiebert XDP Liebert XDC Liebert XDP/Liebert XDC Pumped R-134a Circuit Volume Determining Refrigerant VolumeSystem refrigerant charge for the supply and return mains Return Line Diameter 5/8 Return Line DiameterLiebert XDC DX R-407c Circuit Volume-Air Cooled Units Calculating Refrigerant Charge-ExampleCalculating refrigerant charge-example Worksheet to calculate refrigerant chargeChilled Water Piping ElectricalOutdoor condenser charge-R-407c Indoor water/glycol cooled module R-407c refrigerant chargeLiebert XDO Standard Features Optional Features Liebert XDOLeft Side XDO 24-1/8 Rear of XDO Liebert XDO internal mounting location Liebert XDV Standard Features Liebert XDO top and front electrical access pointsOptional Features-Liebert XDV Liebert XDV dimensionsDetail Area a Detail a Power Source Liebert XDV electrical connections for CSA-approved units Suspending single Liebert XDV from Unistruts Page Liebert XDP Liebert Xdcf Standard FeaturesXD CoolFrame, XDH, XDO or XDV Liebert TM Liebert Xdcf Mechanical ConsiderationsReturn Pipe Liebert Xdcf Piping Connection Methods and Points Liebert Xdcf Installation ConsiderationsEgenera BladeFrame Optional Features-Liebert XDH Liebert XDH Standard FeaturesHeader System Liebert XDH dimensions Supply and return piping connectionsOr 2-5/8 O.D Rear XD Cooling Module Either 5/8 or 7/8Recommended Arc Refer to for detailsLiebert XD Flex Pipe Kit Liebert XD Flex Pipe assemblies, supply and returnLiebert XD Liebert XDV CoolFrame Liebert XDHPiping Installation Method prefabricated headers Liebert XD Piping Dimensions and FeaturesTwo-port prefabricated piping legend Four-port prefabricated piping legend Branch Piping Standard Run Long Run Four Port 186551G21Five-port prefabricated piping legend Branch Piping Standard Run Long Run Five PortTen-port prefabricated piping legend Branch Piping Standard Run Long Run Ten Port 186650G51Liebert XDP Standard Features 33-1/8 990 1067 XDP160Unit piping outlet connection sizes, inches, OD Cu Model Pipe Connection Point 50/60 HZEnclosure Cover Customer Power Liebert XDC Standard Features Liebert XDC Optional FeaturesLiebert XDC piping locations Liebert XD Chiller piping connection sizesLiebert XDC Water/Glycol Piping Connection Sizes Piping locations-floor stand and valve assembly Front view of Liebert XDC and electrical enclosures Switch Transformer Electrical handy box, factory-installed with cover Liebert XDC Extra Low Voltage field connections points Liebert XDC160 specifications Performance Data Heat Rejection EquipmentPiping Connections Performance Data204 Liebert XDP160 specifications Liebert XDO16 specifications Pipe Connections without flex pipe Liebert XDO20 specificationsSides, Front and Rear Liebert XDO20 dimensions-domestic and export Liebert XDV8 specifications Liebert XDV10 specifications Liebert XDV10 dimensions-domestic and export Liebert XDV8 dimensions-domestic and exportLiebert Xdcf specifications Liebert XDH specifications Specifications Specifications Page Ne t ItiTi n That
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