1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULUNDERWRITERS LABORATORIES INC. CERTIFICATION REQUIREMENT DECISIONThis Certification Requirement Decision is prepared and published by Underwriters Laboratories Inc.(UL). It is normative for the a
2、pplicable UL Product Certification Program(s); however, it is currently notpart of the UL Standard(s) referenced below.Product Category (CCN): SEHU, SEYW, SFAU2, SFCS, SFJQ, SKXY, SLPR, SLRG,SLSV, SMGT, SMUR, SNHZ, SNLT, SNOY, SNVX, SOJVStandard Number: UL 207Standard Title: Standard for Refrigerant
3、-Containing Components and Accessories,NonelectricalEdition Date: April 20, 2009Edition Number: 8Section / Paragraph Reference: 12.1.2, 12.1.2.1, 12.1.4 12.1.6, 22.11Subject: Revisions to Permit Certain High-Side Components Based on a ReducedTest PressureSupersedes prior Certification Requirement De
4、cision issued September 13, 2013DECISION:12.1 Refrigerant-containing parts: high side12.1.2 Except as specified in 12.1.4, aA component or section of a component exposed to high sidepressure shall: withstand without failure a pressure equal to the higher of five times the:a) Refrigerant minimum high
5、 side design pressure specified in 11.2(b) or (c);b) Design pressure marked on the component;c) Start-to-discharge pressure of the relief device, if the component is intended to be protectedby a pressure relief device; ord) Nominal rated rupture pressure (see 3.4.16.1) of a rupture member.a) Withsta
6、nd without failure a pressure equal to five times the higher of the pressures specifiedin 12.1.2.1; or,b) Comply with the Fatigue Test in Clause 14; or,c) Withstand without failure a pressure equal to three times the higher of the pressuresspecified in 12.1.2.1, if the component additionally complie
7、s with 12.1.4.12.1.2.1 In reference to 12.1.2(a) and (c), the test pressures shall be based on the higher of the following:a) Refrigerant minimum high side design pressure specified in 11.2(b) or (c);b) Design pressure marked on the component;c) Start-to-discharge pressure of the relief device, if t
8、he component is intended to be protectedby a pressure relief device; ord) Nominal rated rupture pressure (see 3.4.16.1) of a rupture member.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL12.1.4 If the test specified in 12.1.2 is not conducted
9、, a component shall be subjected to the Fatigue Test,Clause 14.A refrigerant containing component complying with 12.1.2(c), shall be intended for use in arefrigeration system in which the critical pressure of the refrigerant is designed to be exceeded. Inaddition, the component shall be provided wit
10、h either:a) A pressure relief valve complying with Clause 9; orb) The marking specified in 22.10.1.12.1.5 In addition to complying with 12.1.2 or 12.1.4, a component which is provided with a fusible plugshall withstand without failure a pressure equal to the smaller of 2-1/2 times the:a) Vapor press
11、ure of the refrigerant at the relief temperature of the fusible plug, orb) Critical pressure of the refrigerant used.12.1.6 In reference to 12.1.2(b) 12.1.4, unless the Fatigue Test in Section 14 is used for determiningcompliance, refrigerant-containing components intended to utilize carbon dioxide
12、(R744) in a secondaryloop or a cascade system shall have an ultimate strength of not less than five times the start-to-dischargevalue of the pressure relief valve and not less than 2500 psig (17238 kPa).MARKING22 General22.10.1 The marking referenced in 12.1.4(b) shall be legibly and permanently mar
13、ked on the refrigerantcontaining component with the following or equivalent: “CAUTION Risk of High Pressure. Thiscomponent shall be installed along with a pressure relief valve set to discharge at no higher than a. Thiscomponent is intended for systems in which the critical pressure of the refrigera
14、nt will be exceeded. Therelief valve shall comply with the requirements of ASME Section VIII, be marked “UV” and sized based onthe refrigeration system capacity.”22.10.2 In reference to 22.10.1, the symbol “a” denotes the design pressure of the refrigerant containingcomponent in both English units (
15、e.g., psig) and SI units (e.g., MPa).RATIONALE FOR DECISION:Manufacturers are looking to create higher efficiency and environmentally friendly (Green) refrigerationproducts. One option is for such products to employ a refrigerant such as carbon dioxide (R-744) that maybe in a state that exceeds the
16、critical pressure of the refrigerant (i.e, transcritical).These requirements are intended to harmonize with similar requirements that were recently publishedwithin the Standard for Commercial Refrigerators and Freezers, UL 471. In brief, refrigerant containingcomponents used within refrigeration sys
17、tems in which the critical pressure of the refrigerant will beexceeded will now only need to be subjected to three times the applicable pressure rather than thepresent five times pressure (or three times pressure together with and as part of the fatigue cycling test).However, for such components, th
18、ese requirements would drive the need for either a pressure relief valveor a caution marking to be located on the component.Paragraph 12.1.2 is being revised and Paragraph 12.1.2.1 is being added to better organize therequirements applicable to high side refrigerant containing components with the ad
19、dition of these newrequirements.STANDARD NUMBER: UL 207 -2-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULParagraph 12.1.4 is being revised to require a refrigerant containing component complying with Paragraph12.1.2(c) to be provided with ei
20、ther a pressure relief valve or a caution marking. The caution marking isintended to cause the installer to be aware of the need to provide a pressure relief valve as part of theend-use product refrigeration system. The reference to the Fatigue Test which was previously inParagraph 12.1.4 and is bei
21、ng removed is now included into Paragraph 12.1.2(b).Paragraphs 12.1.5 and 12.1.6 are being revised for consistency with the revisions made to Paragraphs12.1.2 and 12.1.4.Paragraphs 22.10.1 and 22.10.2 are being added to require the caution marking as referenced by therequirement in Paragraph 12.1.4(
22、b).These revisions reflect present practice.Copyright 2013 Underwriters Laboratories Inc.UL, in performing its functions in accordance with its objectives, does not guarantee or warrant thecorrectness of Certification Requirement Decisions it may issue or that they will be recognized or adoptedby an
23、yone. Certification Requirement Decisions are the opinion of Underwriters Laboratories Inc. inpractically applying the requirements of the standard. They do not represent formal interpretations of thestandard under American National Standards Institute (ANSI) processes. UL shall not be responsible t
24、oanyone for the use of or reliance upon Certification Requirement Decisions by anyone. UL shall not incurany obligation or liability for damages, including consequential damages, arising out of or in connectionwith the use or reliance upon Certification Requirement Decisions. The electronic version
25、of theCertification Requirement Decision is the current version and previously printed copies may be outdated.This document is published as a service to ULs certification customersSTANDARD NUMBER: UL 207 -3-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULSTANDARD NUMBER: UL 207 -4-No Text on This Page
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