ASHRAE_37_2009

ASHRAE STANDARDASHRAE STANDARD ANSI/ASHRAE Standard 37-2009 (Supersedes ANSI/ASHRAE Standard 37-2005) Methods of Testing for Rating Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment Approved by the ASHRAE Standards Committee on June 20, 2009; by the ASHRAE Board of Directors on June 24, 2009; and by the American National Standards Institute on June 25, 2009. ASHRAE Standards are scheduled to be updated on a five-year cycle; the date following the standard number is the year of ASHRAE Board of Directors approval. The latest copies may be purchased from ASHRAE Cus- tomer Service, 1791 Tullie Circle, NE, Atlanta, GA 30329-2305. E-mail: orders@ashrae.org. Fax: 404-321- 5478. Telephone: 404-636-8400 (worldwide) or toll free 1-800-527-4723 (for orders in US and Canada). © Copyright 2009 American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. ISSN 1041-2336 American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. 1791 Tullie Circle NE, Atlanta, GA 30329 www.ashrae.orgCopyright ASHRAE Provided by IHS under license with ASHRAE Licensee=Ferris State University/5966314001 Not for Resale, 07/25/2011 12:57:38 MDTNo reproduction or networking permitted without license from IHS --`,``,,,`,,``,,````,,````,`,`,-`-`,,`,,`,`,,`--- ASHRAE STANDARDS COMMITTEE 2008–2009 Hugh F. Crowther, Chair Steven T. Bushby, Vice-Chair Robert G. Baker Michael F. Beda Donald L. Brandt Paul W. Cabot Kenneth W. Cooper Samuel D. Cummings, Jr. K. William Dean Martin Dieryckx Robert G. Doerr Allan B. Fraser Nadar R. Jayaraman Byron W. Jones Jay A. Kohler Carol E. Marriott Merle F. McBride Frank Myers H. Michael Newman Janice C. Peterson Douglas T. Reindl Lawrence J. Schoen Boggarm S. Setty Bodh R. Subherwal William F. Walter Michael W. Woodford David E. Knebel, BOD ExO Andrew K. Persily, CO Stephanie Reiniche, Manager of Standards SPECIAL NOTE This American National Standard (ANS) is a national voluntary consensus standard developed under the auspices of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Consensus is defined by the American National Standards Institute (ANSI), of which ASHRAE is a member and which has approved this standard as an ANS, as “substantial agreement reached by directly and materially affected interest categories. This signifies the concurrence of more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that an effort be made toward their resolution.” Compliance with this standard is voluntary until and unless a legal jurisdiction makes compliance mandatory through legislation. ASHRAE obtains consensus through participation of its national and international members, associated societies, and public review. ASHRAE Standards are prepared by a Project Committee appointed specifically for the purpose of writing the Standard. The Project Committee Chair and Vice-Chair must be members of ASHRAE; while other committee members may or may not be ASHRAE members, all must be technically qualified in the subject area of the Standard. Every effort is made to balance the concerned interests on all Project Committees. The Assistant Director of Technology for Standards and Special Projects of ASHRAE should be contacted for: a. interpretation of the contents of this Standard, b. participation in the next review of the Standard, c. offering constructive criticism for improving the Standard, or d. permission to reprint portions of the Standard. DISCLAIMER ASHRAE uses its best efforts to promulgate Standards and Guidelines for the benefit of the public in light of available information and accepted industry practices. However, ASHRAE does not guarantee, certify, or assure the safety or performance of any products, components, or systems tested, installed, or operated in accordance with ASHRAE’s Standards or Guidelines or that any tests conducted under its Standards or Guidelines will be nonhazardous or free from risk. ASHRAE INDUSTRIAL ADVERTISING POLICY ON STANDARDS ASHRAE Standards and Guidelines are established to assist industry and the public by offering a uniform method of testing for rating purposes, by suggesting safe practices in designing and installing equipment, by providing proper definitions of this equipment, and by providing other information that may serve to guide the industry. The creation of ASHRAE Standards and Guidelines is determined by the need for them, and conformance to them is completely voluntary. In referring to this Standard or Guideline and in marking of equipment and in advertising, no claim shall be made, either stated or implied, that the product has been approved by ASHRAE. ASHRAE Standard Project Committee 37 Cognizant TC: TC 8.11, Unitary and Room Air Conditioners and Heat Pumps SPLS Liaison: Matt R. Hargan Alberto A. da Rosa, Chair* Greg S. Bennett Darryl Denton* Piotr A. Domanski Brian P. Dougherty* Byron F. Horak* H. Michael Hughes* Birol I. Kilkis* Arvo Lannus *Denotes members of voting status when the document was approved for publication Copyright ASHRAE Provided by IHS under license with ASHRAE Licensee=Ferris State University/5966314001 Not for Resale, 07/25/2011 12:57:38 MDTNo reproduction or networking permitted without license from IHS --`,``,,,`,,``,,````,,````,`,`,-`-`,,`,,`,`,,`--- CONTENTS ANSI/ASHRAE Standard 37-2009 Methods of Testing for Rating Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment SECTION PAGE Foreword................................................................................................................................................................... 2 1 Purpose .......................................................................................................................................................... 2 2 Scope ............................................................................................................................................................. 2 3 Definitions....................................................................................................................................................... 2 4 Classifications................................................................................................................................................. 2 5 Instruments..................................................................................................................................................... 3 6 Airflow and Air Differential Pressure Measurement Apparatus....................................................................... 3 7 Methods of Testing and Calculation................................................................................................................ 9 8 Test Procedures............................................................................................................................................ 18 9 Data to be Recorded .................................................................................................................................... 22 10 Test Results .................................................................................................................................................. 24 11 Symbols used in Equations .......................................................................................................................... 25 12 Reference Properties and Data .................................................................................................................... 27 13 References ................................................................................................................................................... 27 Informative Appendix A:Classifications of Unitary Air Conditioners and Heat Pumps........................................ 28 NOTE When addenda, interpretations, or errata to this standard have been approved, they can be downloaded free of charge from the ASHRAE Web site at http://www.ashrae.org. © Copyright 2009 American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. 1791 Tullie Circle NE Atlanta, GA 30329 www.ashrae.org All rights reserved. © 2009, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (www.ashrae.org). For personal use only. Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE’s prior written permission. Copyright ASHRAE Provided by IHS under license with ASHRAE Licensee=Ferris State University/5966314001 Not for Resale, 07/25/2011 12:57:38 MDTNo reproduction or networking permitted without license from IHS - - ` , ` ` , , , ` , , ` ` , , ` ` ` ` , , ` ` ` ` , ` , ` , - ` - ` , , ` , , ` , ` , , ` - - - 2 ANSI/ASHRAE Standard 37-2009 (This foreword is not part of this standard. It is merely informative and does not contain requirements necessary for conformance to the standard. It has not been pro- cessed according to the ANSI requirements for a stan- dard and may contain material that has not been subject to public review or a consensus process. Unresolved objectors on informative material are not offered the right to appeal at ASHRAE or ANSI.) FOREWORD This is a revision of Standard 37-2005. This standard was prepared under the auspices of the American Heating Refrig- erating and Air-Conditioning Engineers (ASHRAE). It may be used, in whole or in part, by an association or government agency with due credit to ASHRAE. Adherence is strictly on a voluntary basis and merely in the interests of obtaining uni- form standards throughout the industry. This version updates the references section, superscripts references cited in the text and corrects the erratum in section 7.7.2.1. 1. PURPOSE 1.1 The purpose of this standard is to provide test methods for determining the cooling capacity of unitary air-condition- ing equipment and the cooling or heating capacities, or both, of unitary heat pump equipment. 1.2 These test methods do not specify methods of establish- ing ratings that involve factors such as manufacturing toler- ances and quality control procedures. 2. SCOPE 2.1 This standard applies to electrically driven mechani- cal-compression unitary air conditioners and heat pumps con- sisting of one or more assemblies that include an indoor air coil(s), a compressor(s), and an outdoor coil(s). Where such equipment is provided in more than one assembly, the sepa- rated assemblies are designed to be used together. 2.2 This standard does not include methods of testing the following: (a) cooling coils for separate use (b) condensing units for separate use (c) room air conditioners (d) heat-operated unitary equipment (e) liquid chilling packages (f) multiple indoor air coils operating simultaneously in heat- ing and cooling modes 3. DEFINITIONS air, standard: dry air having a mass density of 1.204 kg/m3 (0.075 lb/ft3). apparatus: as used in this standard, this term refers exclu- sively to test room facilities and instrumentation. capacity, heating: the rate, expressed in watts (Btu/h), at which the equipment adds heat to the air passing through it under specified conditions of operation. capacity, latent cooling: the rate, expressed in watts (Btu/h), at which the equipment removes latent heat from the air pass- ing through it under specified conditions of operation. capacity, sensible cooling: the rate, expressed in watts (Btu/h), at which the equipment removes sensible heat from the air passing through it under specified conditions of operation. capacity, total cooling: the rate, expressed in watts (Btu/h), at which the equipment removes heat from the air passing through it under specified conditions of operation. coil, indoor: the heat exchanger that removes heat from or adds heat to the conditioned space. coil, outdoor: the heat exchanger that rejects heat to or absorbs heat from a source external to the conditioned space. equipment: as used in this standard, this term refers exclu- sively to the unitary equipment to be tested. equipment, unitary: this term shall be defined as provided in Section 2 and Section 4. indoor side: that part of the system that removes heat from or adds heat to the indoor airstream. outdoor side: that part of the system that rejects heat to or absorbs heat from a source external to the indoor airstream. pressure, standard barometric: 101.325 kPa (14.696 psi). refrigerant, volatile: a refrigerant that changes from the liquid to the vapor state in the process of absorbing heat. shall: where “shall” or “shall not” is used for a provision, that provision is mandatory if compliance with the standard is claimed. should, recommended, or it is recommended: “should,” “recommended,” or “it is recommended” are used to indicate provisions that are not mandatory but that are desirable as a good practice. 4. CLASSIFICATIONS Unitary equipment within the scope of this standard may be classified as follows: 4.1 Component Arrangement: (a) Units employing compressor(s), indoor air coil(s), and outdoor coil(s) in a single package assembly. (b) Units employing compressor(s) and indoor coil(s) in one or more assemblies with remote outdoor coil(s). (c) Units employing indoor coil assemblies, with outdoor coil(s) and compressor(s) in one or more assemblies. Copyright ASHRAE Provided by IHS under license with ASHRAE Licensee=Ferris State University/5966314001 Not for Resale, 07/25/2011 12:57:38 MDTNo reproduction or networking permitted without license from IHS - - ` , ` ` , , , ` , , ` ` , , ` ` ` ` , , ` ` ` ` , ` , ` , - ` - ` , , ` , , ` , ` , , ` - - - ANSI/ASHRAE Standard 37-2009 3 4.2 Method of Outdoor Coil Heat Exchange: (a) air, (b) liquid, and (c) evaporative cooled condensing. Note: Related Air-Conditioning and Refrigeration Institute (ARI) classifications for unitary air conditioners and heat pumps are given in Tables A-1 and A-2, respectively, in Appendix A, and are illustrative but not restrictive. 5. INSTRUMENTS 5.1 Temperature Measuring Instruments 5.1.1 All temperature measurements (with the exception of dew point temperature) shall be made in accordance with ANSI/ASHRAE Standard 41.1.1 5.1.2 If used in determining the water vapor content of the air, dew point hygrometers shall be applied as specified in ANSI/ASHRAE Standard 41.62 and shall be accurate to within ±0.2°C (0.4°F). 5.1.3 Inlet air temperature measurements are to be taken upstream of static pressure taps on the inlet duct (if installed). Outlet air temperature measurements shall be taken down- stream of the static pressure taps on the outlet. 5.2 Refrigerant, Liquid, and Barometric Pressure Mea- suring Instruments 5.2.1 Pressure measurements shall be made with one or more of the following instruments: (a) liquid column (b) Bourdon tube gauge (c) electronic pressure transducer ASHRAE Standard 41.33 should be referred to for infor- mation on the above instruments. 5.2.2 The accuracy of the pressure measuring instruments shall permit measurements to within ±2.5% of the reading. 5.2.3 Calibration of the pressure measuring instrument shall be with respect to a deadweight tester or by comparison with a liquid column. 5.2.4 In no case shall the smallest scale division of the pressure measuring instrument exceed two times the specified accuracy. 5.3 Air Differential Pressure and Airflow Measurements 5.3.1 The static pressure difference across nozzles and velocity pressures at nozzle throats shall be measured with manometers or electronic pressure transducers that have been calibrated against a pressure standard to within ±1.0% of the reading. The resolution of the device shall be equal to or less than 2.0% of the reading. 5.3.2 Duct static pressure shall be measured with one or more manometers or electronic pressure transducers that are accurate to within ±2.5 Pa (±0.01 in. H2O). 5.3.3 Areas of nozzles shall be determined by measuring their diameters to within ±0.20% in four places approxi- mately equally spaced around the nozzle in each of two planes through the nozzle throat, one at the outlet and the other in the straight section near the radius. 5.4 Electrical Instruments 5.4.1 Electrical measurements shall be made with indicat- ing or integrating instruments. 5.4.2 Instruments used for measuring the electrical power input to fan motors, compressor motors, or other equipment accessories shall be accurate to within ±2.0% of the reading. Note: For an efficiency rating purpose, a more accurate mea- surement of the electrical power input may be required. 5.4.3 Instruments used for measuring the electrical power input to heaters or other apparatus furnishing heat loads (see 7.7.1.2 and Figure 10) shall be accurate to within ±1.0% of the quantity measured. 5.4.4 Voltages shall be measured at the equipment termi- nals. Instruments used for measuring voltage shall be accurate to within ±1.0% of the reading. 5.5 Volatile Refrigerant Flow Measurement 5.5.1 Volatile refrigerant flow shall be measured with an integrating flow measuring system that is accurate to within ±1.0% of the reading. 5.6 Liquid Flow Measurement 5.6.1 Water and brine flow rates shall be measured with a liquid flow meter or quantity meter that is accurate to within ±1.0% of the reading. 5.6.2 Condensate collection rates shall be determined using a liquid quantity meter that is accurate to within ±1.0% of the reading. 5.7 Speed Measuring Instruments 5.7.1 Speed measurements shall be made with a revolu- tion counter, tachometer, stroboscope, or oscilloscope that is accurate to within ±1.0% of the reading. 5.8 Time and Mass Measurements 5.8.1 Time interval measurements shall be made with an instrument that is accurate to within ±0.2% of the reading. 5.8.2 Mass measurements shall be made with an appara- tus that is accurate to within ±1.0% of the reading. 5.9 Volatile refrigerant mass composition measurements for zeotropic refrigerants shall be made using an instrument that is in accordance with ARI Standard 700-95.4 6. AIRFLOW AND AIR DIFFERENTIAL PRESSURE MEASUREMENT APPARATUS 6.1 Enthalpy Apparatus. Recommended configurations for the test apparatus are provided below. In all cases, suitable means for determining the dry-bulb temperature and water vapor content of the air entering and leaving the unit and for measuring the external resistance to airflow shall be provided. 6.1.1 The arrangement for the tunnel air-enthalpy method is shown schematically in Figure l. An airflow measuring device is attached to the equipment air discharge (indoor or outdoor, or both, as applicable). This device discharges directly into the test room or space, which is provided with Copyright ASHRAE Provided by IHS under license with ASHRAE Licensee=Ferris State University/5966314001 Not for Resale, 07/25/2011 12:57:38 MDTNo reproduction or networking permitted without license from IHS - - ` , ` ` , , , ` , , ` ` , , ` ` ` ` , , ` ` ` ` , ` , ` , - ` - ` , , ` , , ` , ` , , ` - - - 4 ANSI/ASHRAE Standard 37-2009 suitable means for maintaining the air entering the unit at the desired wet- and dry-bulb temperatures. 6.1.2 An arrangement for a typical loop air-enthalpy method is illustrated in Figure 2. The unit is installed as it would be for the tunnel arrangement. The airflow measuring device discharge is connected to suitable reconditioning equipment that is, in turn, connected to the equipment inlet. The resulting closed test “loop” shall be sealed so that air leakage at places that would influence capacity measurements does not exceed 1.0% of the test airflow rate. The dry-bulb and wet-bulb temperatures of the air surrounding the equip- ment shall be maintained to within ±3°C (±5°F) of the speci- fied indoor and outdoor conditions. 6.1.3 The arrangement for th