1、 ANSI/AHRI Standard 900 (formerly ARI Standard 900) 2014 Standard for Performance Rating of Thermal Storage Equipment Used for Cooling AHRI Stand rd 900 (I-P) Price $25.00 (M) $50.00 (NM) Copyright 2014, by Air-Conditioning, Heating, and Refrigeration Institute Printed in U.S.A. Registered United St
2、ates Patent and Trademark Office IMPORTANT SAFETY DISCLAIMER AHRI does not set safety standards and does not certify or guarantee the safety of any products, components or systems designed, tested, rated, installed or operated in accordance with this standard/guideline. It is strongly recommended th
3、at products be designed, constructed, assembled, installed and operated in accordance with nationally recognized safety standards and code requirements appropriate for products covered by this standard/guideline. AHRI uses its best efforts to develop standards/guidelines employing state-of-the-art a
4、nd accepted industry practices. AHRI does not certify or guarantee that any tests conducted under its standards/guidelines will be non-hazardous or free from risk. Note: This standard supersedes AHRI 900-2010. For SI ratings, see AHRI Standard 901 (SI) 2014. i TABLE OF CONTENTS SECTION PAGE Section
5、1. Purpose .1 Section 2. Scope 1 Section 3. Definitions1 Section 4. Classifications 3 Section 5. Test Requirements .4 Section 6. Rating Requirements 5 Section 7. Minimum Data Requirements for Published Ratings 7 Section 8. Marking and Nameplate Data 7 Section 9. Conformance Conditions .8 TABLES Tabl
6、e 1. Classification of Thermal Storage Equipment .4 Table 2. Limits of Mapped Rating Conditions and Method of Testing .6 Table 3A. Supplier Specified Data Example Design Day .9 Table 3B. Supplier Specified Discharge Data for Unitary Thermal Storage Systems .11 Table 4. Charge Cycle Rating Conditions
7、 for Unitary Thermal Storage Systems 11 APPENDICES Appendix A. References Normative .12 Appendix B. References Informative .13 Appendix C. Method of Testing for Rating Thermal Storage Devices Which Employ the Same Secondary Coolant for the Charge and Discharge Cycles Normative 14 Appendix D. Method
8、of Testing for Rating Unitary Thermal Storage Systems Normative 27 ii APPENDICES (continued) Appendix E. Method of Field Testing for Rating Thermal Storage Devices Normative 39 Appendix F. Method of Testing for Rating Thermal Storage Devices Which Employ Different Heat Transfer Fluids for the Charge
9、 Cycle and the Discharge Cycle Normative .51 TABLES FOR APPENDICES Table C1. Temperature Comparison Charge and Discharge Cycles .26 Table D1. Power Comparison Charge Cycle Test 38 Table D2. Temperature Comparison Discharge Cycle Test .38 Table E1. Temperature Comparison Charge and Discharge Cycles .
10、50 Table F1. Temperature Comparison Charge and Discharge Cycles 68 FIGURES FOR APPENDICES Figure C1. Thermal Storage Device Test Apparatus .16 Figure D1. Discharge Cycle Test Apparatus 28 Figure E1. Thermal Storage Device Test Apparatus .40 Figure F1. Discharge Cycle Test Apparatus 52 Figure F2. Ref
11、rigeration System with Secondary Coolant 54 Figure F3. Refrigeration System with Direct Expansion Feed 54 Figure F4. Refrigeration System with Gravity Feed .55 Figure F5. Refrigeration System with Pumped Overfeed .55 Figure F6. Typical Calorimeter Instrument .57 AHRI STANDARD 900 (I-P)-2014 1 PERFOR
12、MANCE RATING OF THERMAL STORAGE EQUIPMENT USED FOR COOLING Section 1. Purpose 1.1 Purpose. The purpose of this standard is to establish for Thermal Storage Equipment used for cooling: definitions; classifications; test requirements; rating requirements; minimum data requirements for Published Rating
13、s; operating requirements; marking and nameplate data; and conformance conditions. 1.1.1 Intent. This standard is intended for the guidance of the industry, including manufacturers, engineers, installers, contractors, and users. 1.1.2 Review and Amendment. This standard is subject to review and amen
14、dment as the technology advances. Section 2. Scope 2.1 Scope. This standard applies to Thermal Storage Equipment used for cooling which may be charged and discharged with any of a variety of heat transfer fluids. The equipment, as further described in Sections 3 and 4, may be fully factory assembled
15、; assembled on site from factory supplied components; or field erected in accordance with pre-established design criteria. 2.2 Exclusions. This standard does not apply to: 2.2.1 Thermal Storage Equipment with storage capacities of 7 Ton-Hours or less 2.2.2 Thermal Storage Equipment used solely for h
16、eating Section 3. Definitions All terms in this document shall follow the standard industry definitions in the current edition of ASHRAE Terminology website (https:/www.ashrae.org/resources-publications/free-resources/ashrae-terminology) unless otherwise defined in this section. For the convenience
17、of users of this standard, definitions for the more important terms employed in this standard are provided below: 3.1 Ambient Air. The air in the space surrounding the thermal energy storage device. 3.2 Ambient Heat Load. The load (typically expressed in tons) imposed on the storage device due to he
18、at gain from the ambient. 3.3 Charge Fluid. The heat transfer fluid used to remove heat from a Thermal Storage Device. 3.4 Charge Period/Cycle. The Period of time when energy (heat) is removed from the storage device. 3.5 Charge Rate. The rate (typically expressed in tons) at which energy (heat) is
19、removed from the storage device during the Charge Period. 3.6 Discharge Fluid. The heat transfer fluid used to add heat to the Thermal Storage Device. 3.7 Discharge Period/Cycle. The Period of time when energy (heat) is added to the storage device. 3.8 Discharge Rate. The rate (typically expressed i
20、n tons) at which energy (heat) is added to the storage device during the Discharge Period. AHRI STANDARD 900 (I-P)-2014 2 3.9 Fouling Factor Allowance. A thermal resistance included in heat transfer calculations to account for the fouling expected over time on the air, refrigerant, or water side are
21、a of a heat transfer surface. 3.10 Hermetic Compressor. A motor-compressor assembly contained within a gas-tight casing which uses the refrigerant as the motor coolant. This includes semi-hermetic compressors. 3.11 Interval. The time span between individual test readings. 3.12 Load Intensity. The ra
22、tio of the instantaneous load imposed upon the storage device to the Net Usable Storage Capacity of the unit, typically expressed in tons/ton-h. 3.13 Net Storage Inventory. Net accumulated measured Storage Capacity at a given period of time during a 24 hour cycle. 3.14 Open-type Compressor. A refrig
23、erant compressor with a shaft or other moving part extending through the casing to be driven by an outside source of power. 3.15 Period. The one hour time segments into which the total duty cycle of a thermal storage system is divided for the purpose of analysis and evaluation. 3.16 Phase Change Mat
24、erial (PCM). A substance that undergoes changes of state while absorbing or rejecting thermal energy, normally at a constant temperature. 3.17 Published Ratings. Published Ratings for Thermal Storage Equipment are the data and methodology by which the “Supplier Specified Data”, as set forth in Table
25、 3 of this standard, are developed for a specified duty cycle. They may take the form of tables, graphs, or computer programs, as elected by the manufacturer, and shall apply to all units of like nominal size and type (identification) produced by the same manufacturer. 3.17.1 Standard Rating. A rati
26、ng based on tests performed at standard rating conditions. 3.17.2 Mapped Rating(s). Mapped Ratings are ratings falling within certain specified limits that are provided for products which do not have a standard rating condition. They are based upon tests performed across a range of operating conditi
27、ons as defined by the product manufacturer. 3.17.3 Application Rating. A rating, based on tests performed at application rating conditions (other than standard or mapped rating conditions). 3.18 Saturated Evaporator Temperature (SET). The dew point temperature of the refrigerant corresponding to the
28、 saturation pressure at the outlet connection of the evaporator. 3.19 Saturated Return Temperature. The temperature of the refrigerant corresponding to the saturation pressure at the return connection of a Unitary Thermal Storage System. 3.20 Secondary Coolant. Any liquid cooled by a refrigerant and
29、 used for heat transmission without a change in state, having no flash point or a flash point above 150F. 3.21 “Shall“ or “Should. “Shall“ or “Should“ shall be interpreted as follows: 3.21.1 Shall. Where “shall “ or “shall not“ is used for a provision specified, that provision is mandatory if compli
30、ance with the standard is claimed. 3.21.2 Should. “Should“ is used to indicate provisions which are not mandatory, but which are desirable as good practice. 3.22 Storage Capacity. Storage Capacity, as used in this standard, shall be defined as follows: AHRI STANDARD 900 (I-P)-2014 3 3.22.1 Measured
31、Storage Capacity. The Storage Capacity of a Unitary Thermal Storage System (UTSS) determined during a given Storage Cycle in the charge cycle test, typically expressed in ton-h. 3.22.2 Net Usable Storage Capacity. The amount of stored cooling that can be supplied from the storage device at or below
32、the specified cooling supply temperature for a given Charge and Discharge Cycle, typically expressed in Ton-Hours. 3.22.3 Nominal Storage Capacity. A theoretical capacity of the storage device as defined by the storage device manufacturer (which in many cases is greater than the Net Usable Storage C
33、apacity), typically expressed in Ton-Hours. 3.23 Thermal Storage Device. Equipment which stores cooling capacity using sensible and/or latent heat. This equipment may consist solely of a storage means or be packaged with one or more components of a mechanical refrigeration system. 3.24 Thermal Stora
34、ge Equipment. Any one of, or a combination of, Thermal Storage Devices and/or Unitary Thermal Storage Systems, that may include various other components of a mechanical refrigeration package (Section 4). 3.25 Ton-hour (ton-h). The quantity of thermal energy equal to 12,000 Btu or 1 ton of refrigerat
35、ion provided for one hour. 3.26 Unitary Thermal Storage System (UTSS). An assembly of components including a Thermal Storage Device and refrigeration equipment for charging, whose overall performance as a Unitary Thermal Storage System is rated by the manufacturer. Section 4. Classifications 4.1 Cla
36、ssification. Thermal Storage Equipment is broadly classified as either “sensible“ or “latent“, with further delineations as shown in Table 1 and explained in subsequent paragraphs. 4.1.1 Sensible Thermal Storage Equipment. Sensible Thermal Storage Equipment used for cooling typically employs water a
37、s the storage medium. During the Charge Period, warm water from the storage device is chilled to the desired temperature by a water chiller and returned to the storage vessel. During the Discharge (cooling) Period, the chilled water is pumped from the storage vessel to the load and the resultant war
38、m water returned to storage. Any of several methods may be used to keep the warm return water separated from the stored chilled water, including separate or compartmentalized tanks or where only one tank is employed, labyrinths, membranes, or thermal stratification. 4.1.2 Latent Thermal Storage Equi
39、pment. Latent Thermal Storage Equipment is further categorized as ice-on-coil, encapsulated ice or Phase Change Material, ice harvester/chiller, ice slurry, or unitary. 4.1.2.1 Ice-on-Coil. A Thermal Storage Device consisting of coils, plates, or other heat transfer surface submerged in a water fill
40、ed tank. During the Charge Period, an evaporating refrigerant or cold Secondary Coolant is circulated through the coils/plates causing ice to form on the external surfaces. During the Discharge (cooling) Period, either of two methods is typically employed: 4.1.2.1.1 External Melt. With external melt
41、, warm, return water is circulated through the tank, external to the ice formation, whereby it is cooled by the melting ice. Some ice-on-coil devices may also serve as water chillers by circulating warm return water through the tank and over the external surface of the heat exchanger where it is coo
42、led by Secondary Coolant or refrigerant circulating within the exchanger. 4.1.2.1.2 Internal Melt. With internal melt, typically a warm, return, Secondary Coolant is circulated through the coils/plates and cooled as the ice external to the coils/plates is melted. AHRI STANDARD 900 (I-P)-2014 4 4.1.2
43、.2 Encapsulated Ice or Phase Change Material. Thermal Storage Equipment consisting of a tank or vessel densely packed with numerous, relatively small containers in which the storage medium (water-ice or other Phase Change Material such as eutectic salt) is encapsulated. During the Charge Period, wat
44、er or Secondary Coolant, at a temperature below the phase change temperature of the storage media, is circulated through the tank/vessel to effect a phase change (freezing) in the storage medium. During the Discharge Period, warm return water or Secondary Coolant is circulated through the tank/vesse
45、l and cooled as the encapsulated storage media changes phase (melts). 4.1.2.3 Unitary. An assembly of components including a Thermal Storage Device and refrigeration equipment for charging which is rated by the manufacturer as a UTSS. The Thermal Storage Device consists of a heat exchanger submerged
46、 in a water filled tank. During the Charge Period, an evaporating refrigerant or cold Secondary Coolant is circulated through the heat exchanger causing ice to form on the external surface. During the Discharge (cooling) Period, a condensing refrigerant or warm Secondary Coolant is cooled by interna
47、l and/or external melt processes. Table 1. Classification of Thermal Storage Equipment Classification Type Storage Media Charge Fluid Discharge Fluid Sensible Chilled Water Water or other Aqueous Solution Water or other Aqueous Solution Water or other Aqueous Solution Latent Ice-on-Coil (External Me
48、lt) Ice or other Phase Change Material Secondary Coolant Water or Secondary Coolant Refrigerant Ice-on-Coil (Internal Melt) Ice or other Phase Change Material Secondary Coolant Secondary Coolant Encapsulated Ice or Phase Change Material Ice or other Phase Change Material Water Water Secondary Coolan
49、t Secondary Coolant Unitary Ice or other Phase Change Material Refrigerant or Secondary Coolant Refrigerant, Water or Secondary Coolant Section 5. Test Requirements 5.1 Test Requirements. All Standard and Mapped Ratings shall be verified by tests conducted in accordance with the methods, procedures, and instrumentation set forth in Appendices C, D, E or F of this standard, as applicable. 5.2 Tolerances for Thermal Storage Devices. Published Mapped Ratings shall be such that any production Thermal Storage Device, upon test, shall have a Net Usable Storage Capacit
