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vb.net print barcode labels The overall efficiency of the water system becomes WS 38 100 139 273 percent in Software
The overall efficiency of the water system becomes WS 38 100 139 273 percent QR Code ISO/IEC18004 Generator In None Using Barcode generator for Software Control to generate, create QR Code image in Software applications. Decoding QR Code In None Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications. This demonstrates that only slightly more than onefourth of the energy applied to the pump motors is being used for efficient transportation of the water through the system As dramatic as this may seem, there are water systems utilizing constantspeed pumps and mechanical devices to overcome the pump overpressure where less than 10 percent of the energy applied is used to move the needed water through the system at moderate and low loads on the system Create QR Code In Visual C#.NET Using Barcode maker for .NET framework Control to generate, create QR Code 2d barcode image in .NET applications. QR Code Encoder In Visual Studio .NET Using Barcode drawer for ASP.NET Control to generate, create QR Code JIS X 0510 image in ASP.NET applications. Downloaded from Digital Engineering Library @ McGrawHill (wwwdigitalengineeringlibrarycom) Copyright 2006 The McGrawHill Companies All rights reserved Any use is subject to the Terms of Use as given at the website QR Code Maker In .NET Using Barcode encoder for VS .NET Control to generate, create QR Code 2d barcode image in Visual Studio .NET applications. Painting QR Code In Visual Basic .NET Using Barcode printer for VS .NET Control to generate, create Quick Response Code image in .NET framework applications. The Use of Water in HVAC Systems 216 The HVAC World
Create Code 128A In None Using Barcode encoder for Software Control to generate, create ANSI/AIM Code 128 image in Software applications. DataMatrix Generator In None Using Barcode encoder for Software Control to generate, create Data Matrix ECC200 image in Software applications. These equations for energy consumed, energy applied, and system efficiency are for the water system in total Similar evaluations for energy consumption must be made for all parts of a water system to ensure that maximum system efficiency is achieved In Chap 6, wiretowater efficiency for pumping systems was addressed Examples of this efficiency will be found throughout this book The use of Eq 83 to evaluate the efficiency of pumping for an HVAC system may be cumbersome and the answer difficult to determine Also, the use of small pipe and high friction losses may provide a relatively high efficiency for a poorly designed system The use of Eq 83 is more relative than absolute in comparing different piping system designs with the same level of pipe friction Making USS Code 39 In None Using Barcode encoder for Software Control to generate, create ANSI/AIM Code 39 image in Software applications. Drawing UPCA In None Using Barcode generator for Software Control to generate, create UPCA image in Software applications. Energy consumption of water distribution
EAN / UCC  14 Creator In None Using Barcode creation for Software Control to generate, create EAN 128 image in Software applications. Paint Bar Code In None Using Barcode maker for Software Control to generate, create bar code image in Software applications. There are other equations for chilled water and hot water systems that are useful to determine the effectiveness of pumping They are easier to compute than Eq 83 and provide absolute values For example, for chilled water, kW/100 tons 0452 H P E T F (87) Print ISSN In None Using Barcode creator for Software Control to generate, create ISSN  13 image in Software applications. EAN128 Generator In C#.NET Using Barcode printer for .NET Control to generate, create GTIN  128 image in .NET applications. where H P E T
Drawing Bar Code In Visual Studio .NET Using Barcode generator for ASP.NET Control to generate, create barcode image in ASP.NET applications. Generate Linear 1D Barcode In VS .NET Using Barcode printer for ASP.NET Control to generate, create Linear image in ASP.NET applications. system head pump efficiency motor efficiency or wiretoshaft efficiency of a variablespeed drive and motor for variablespeed pumps system temperature difference Painting Barcode In .NET Using Barcode encoder for ASP.NET Control to generate, create bar code image in ASP.NET applications. Encode DataMatrix In None Using Barcode maker for Online Control to generate, create Data Matrix ECC200 image in Online applications. For example, if the system head H is 100 ft, the pump efficiency 82 percent, the wiretoshaft efficiency 89 percent, and the temperature differential 12 F, then kW/100 tons 0452 100 082 089 12 516 kW/100 tons Create USS Code 128 In Visual C#.NET Using Barcode creation for Visual Studio .NET Control to generate, create ANSI/AIM Code 128 image in .NET framework applications. USS128 Printer In ObjectiveC Using Barcode creation for iPad Control to generate, create GTIN  128 image in iPad applications. If flow and watt transmitters are measuring system flow and kilowatts of the pumps for the chilled water, an alternate equation (Eq 85) utilizes values measured from the actual system This equation enables the operators of the water system to measure continuously the energy consumed in distributing the chilled water kW/100 tons 2400 pump kW gal/min T F (88) For example, if secondary pumps are pumping 1000 gal/min at a system temperature difference of 12 F and are consuming 258 kW, then Downloaded from Digital Engineering Library @ McGrawHill (wwwdigitalengineeringlibrarycom) Copyright 2006 The McGrawHill Companies All rights reserved Any use is subject to the Terms of Use as given at the website The Use of Water in HVAC Systems The Use of Water in HVAC Systems 217
kW/100 tons for hot water, 2400 258 1000 12 516 kW/100 tons
kW/1000 mbh
2348 H E T F
(89) where is the specific weight of the hot water at operating temperature See Tables 23 and 24 Like chilled water, if watt transmitters are available to measure the energy input to the hot water pumps, the following equation can be used: kW/1000 mbh 124,700 gal/min pump kW T F (810) For example, if the secondary hot water pumps are pumping 500 gal/min of 180 F water at a system temperature difference of 40 F and are consuming 102 kW, then kW/1000 mbh 124,700 102 500 40 6057 105 kW/1000 mbh where 6057 is the specific weight of water at 180 F Examples of these energy rates in kilowatts per 100 tons or kilowatts per 1000 mbh will be included in various chapters of this book 813 Energy lost to mechanical flowcontrol devices
In this day of concern over energy conservation, as we begin the design of an HVAC water system, it is imperative that we reevaluate our standard practices to see where we are wasting energy With computeraided design, it is much easier to develop partload information and a closer evaluation of diversity on hot and chilled water systems This provides the basis for more efficient piping designs that do not need mechanical devices to circulate the water throughout the system For example, on a recent evaluation of a Midwestern university, a chilled water pumping system was in operation with balance valves on the pump discharges There was a 58lb/in2 pressure drop across these balance valves, and each year around 900,000 kWh was wasted by them As discussed in Chap 2, the thermal equivalent of a brake horsepower is 2545 Btu/h, and that for a kilowatthour is 3412 Btu/h This energy must be accounted for in the calculation of heating and cooling Downloaded from Digital Engineering Library @ McGrawHill (wwwdigitalengineeringlibrarycom) Copyright 2006 The McGrawHill Companies All rights reserved Any use is subject to the Terms of Use as given at the website

