Ashrae Journal - October 2008 - (Page 32) we connect Economic assumptions are those agreed to by the committee responsible for the development of Standard 90.1 for life-cycle cost calculations performed in the development of new requirements in the standard: • Electricity costs: 0.0939 $/kWh; • Electricity escalation rate: 3.7%; • Discount rate: 7%; and • System lifetime: 30 years. The result of the analysis is the flow limits in Table 2 (Table 6.5.4.5 from Standard 90.1-2007). The limits vary as a function of estimated operating hours and whether or not the system is variable flow/variable speed. Figure 7 shows the requirements for constant flow systems operating for less than 2,000 hours per year plotted on a friction chart. Compared to Figure 1, the requirements result in higher friction rates for smaller piping and lower friction rates for piping 5 in. (127 mm) and larger. Limitations for variable flow systems are generally less stringent but stringency increases as operating hours increase. Conclusions Honeywell Analytics introduces the industry’s most controlled ventilation solution: IAQPoint. It’s multilingual, it speaks your language. IAQPoint is the only indoor air quality monitor you will need to satisfy all of your demandcontrolled ventilation bid requirements. It integrates easily with virtually any building automation system through its BACnet, LonWorks, FLN, Modbus or analog outputs. IAQPoint produces three sensor outputs (CO2, temperature and humidity) for the price of a typical single-sensor device. Honeywell designed the IAQPoint to install quickly and easily with a small and sleek enclosure that HVAC system piping is typically sized using rule-ofthumb limits for velocity and friction rates. A spreadsheet has been developed to allow piping to be easily and quickly sized based on life-cycle costs with optional noise and erosion velocity limits. The spreadsheet has been used to establish pipe sizing limits in an addendum to ASHRAE Standard 90.1 and in proposed Standard 189.1P. The spreadsheet also can be used to quickly but accurately calculate pump head, which should result in pump first cost and energy cost savings versus conservative pump head guesstimates. The spreadsheet is free and can be downloaded from www.taylor-engineering.com/publications/ design_guides.shtml. References the factory meaning you will spend less time installing the units. IAQPoint is ideal for towers or any environment where money can Think of us as your partner for Indoor Air Quality/Demand Control Ventilation solutions. Honeywell Analytics. Experts in gas detection. To learn more, call 1-800-563-2967, visit www.vulcaininc.com or email detectgas@honeywell.com for a free copy of Gas Book, our 84-page guide to gas detection. © 2008 Honeywell International Inc. All rights reserved. 1. Based on ASHRAE Handbook—Fundamentals, Chapter 36, Figure 4. 2. “EDR Cool-Tools Pipe Size Optimization Spreadsheet.” Free download available from the developer’s Web site at www.taylor-engineering. com/publications/design_guides.shtml. 3. 2008 RS Means Mechanical Cost Data. Kingston, Mass.: RSMeans. 4. ASHRAE Handbook—Fundamentals, Chapter 2, Figure 13. 5. Carrier. 1960. “System Design Manual, Piping Design.” Syracuse, N.Y.: Carrier Air Conditioning Company. 6. ASHRAE Handbook—Fundamentals, Chapter 36. 7. HVAC Noise Design Guide. Unpublished. Oakland, Calif.: Wilson Ihrig Associates. 8. ANSI/ASHRAE/IESNA Standard 90.1-2007, Energy Standard for Buildings Except Low-Rise Residential Buildings. 9. ASHRAE/IESNA/USGBC Standard 189.1P, Standard for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings. Proposed standard, not yet published. www.info.hotims.com/16018-36 32 ASHRAE Journal October 2008 http://www.taylor-engineering.com/publications/design_guides.shtml http://www.taylor-engineering.com/publications/design_guides.shtml http://www.taylor-engineering.com/publications/design_guides.shtml http://www.taylor-engineering.com/publications/design_guides.shtml http://www.vulcaininc.com http://www.vulcaininc.com http://www.info.hotims.com/16018-36
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