1、ANSIZ21.711993AUTOMATIC INTERMITTENTPILOT IGNITION SYSTEMS FORFIELD INSTALLATIONSecond Edition - 1993Printed in U.S.A.byAmerican Gas Association Laboratories8501 East Pleasant Valley RoadCleveland, Ohio 44131ApprovedJanuary 13, 1993AMERICAN NATIONALSTANDARDS INSTITUTE, INC.Copyright 1993, American G
2、as AssociationPermission is granted to republish material herein in laws orordinances, and in regulations, administrative orders, or similar documentsissued by public authorities. Those desiring permission for other republicationshould consult the American Gas Association Laboratories, 8501 East Ple
3、asantValley Road, Cleveland, Ohio 44131.PREFACEThis publication represents a basic standard for safe operation,substantial and durable construction, and acceptable performance for automaticintermittent pilot ignition systems for field installation. It is the result of years ofexperience in the utili
4、zation of gas, supplemented by extensive research.Nothing in this standard is to be considered in any way as indicating ameasure of quality beyond compliance with the provisions it contains. It isdesigned to allow compliance of automatic intermittent pilot ignition systems forfield installation, the
5、 construction and performance of which may exceed thevarious provisions specified herein. In its preparation, full recognition has beengiven to possibilities of improvement through ingenuity of design. As progresstakes place, revisions may become necessary. When they are believed desirable,recommend
6、ations should be forwarded to the Chairman of Accredited StandardsCommittee Z21, 8501 East Pleasant Valley Road, Cleveland, Ohio 44131.Safe and satisfactory operation of an automatic intermittent pilot ignitionsystem for field installation depends to a great extent upon its proper installation,and i
7、t should be installed in accordance with the National Fuel Gas Code, ANSIZ223.1, manufacturers installation instructions and local municipal codes.Users of this American National Standard are advised that thedevices/products/activities within its scope may be subject to regulation at theFederal, sta
8、te or local level. Users are strongly urged to investigate this possibilitythrough appropriate channels. In the event of a conflict with this standard, theFederal, state or local regulation should be followed.CAUTION NOTICE:MThis American National Standard may be revised orwithdrawn at any time. The
9、 procedures of the American National StandardsInstitute, Inc., require that action be taken to reaffirm, revise or withdraw thisstandard no later than five (5) years from the date of approval. Purchasers ofAmerican National Standards may receive current information on all standards bycalling or writ
10、ing the American National Standards Institute, Inc., 11 West 42ndStreet, New York, N.Y. 10036, (212) 642-4900.EFFECTIVE DATE:MAn organization using this standard for product evaluationas a part of its certification program will normally establish the date by which allproducts certified by that organ
11、ization should comply with this standard.HISTORY OF THE DEVELOPMENT OF STANDARDFOR AUTOMATIC INTERMITTENT PILOT IGNITIONSYSTEMS FOR FIELD INSTALLATION(This History is informative and is not part of the standard.)At its April 12, 1978 meeting, AmericanNational Standards Committee Z21 consideredretrof
12、it measures for gas-fired appliances for thepurpose of fuel conservation which were suggestedby the Federal Energy Administration (nowDepartment of Energy). The Z21 Committeereferred these suggested retrofit measures to itsappropriate Z21 standards developing groups forconsideration.At its February
13、22, 1979 meeting, the Z21 GasAppliance Thermostat and Automatic Gas IgnitionSystems Working Committee considered theFederal Energy Administrations suggestion of fieldinstalling electric ignition systems to replacecontinuous pilots on already installed gasappliances.After due consideration, the Worki
14、ngCommittee agreed that a standard for retrofitignition systems should be developed but, forreasons of safety, limited the scope of the standardto intermittent pilot ignition systems adapted toexisting continuous pilots on listed gas-firedheating appliances and boilers equipped withatmospheric burne
15、rs and not of the direct venttype.The Working Committee assigned thepreparation of the draft standard to an ad hocworking group comprised of members of theStandards Review Task Group of the ControlsDivision of the Gas Appliance ManufacturersAssociation and representatives of utilities andcertifying
16、agencies.At its April 11, 1979 meeting, the Z21Committee concurred with its Working Committeesefforts to develop a draft standard for intermittentpilot ignition systems for field installation.By letter ballots of September 11, 1979 theWorking Committee and the Z21 Control DevicesSubcommittee approve
17、d the first draft of thestandard which was distributed for review andcomment during October 1979.The Working Committee, at its December13-14, 1979 meeting, reconsidered the draftstandard in light of comments received andreturned it to the ad hoc working group with therecommendation that the standard
18、 be expanded todifferentiate between those ignition systems forinstallation on appliances using natural gas andthose for installation on appliances using liquefiedpetroleum gases.A second draft of the proposed standard,modified as noted above, was approved by letterballot by the Working Committee an
19、d the ControlDevices Subcommittee and redistributed for reviewand comment during September 1980.At its October 1, 1980 meeting, the WorkingCommittee considered the second draft of thestandard in light of comments received and, withminor modifications, submitted the revisedstandard to the Control Dev
20、ices Subcommitteewhich, by letter ballot dated December 5, 1980,recommended it to the Z21 Committee. The Z21Committee in a letter ballot dated December 31,1980 approved the proposed standard, as modified,for submittal to the American National StandardsInstitute.This, the first edition of the standar
21、d forautomatic intermittent pilot ignition systems forfield installation, was subsequently approved asAmerican National Standard by the AmericanNational Standards Institute, Inc., on November 3,1981.This, the second edition of the standard forautomatic intermittent pilot ignition systems forfield in
22、stallation, was subsequently approved asAmerican National Standard by the AmericanNational Standards Institute, Inc., on January 13,1993.Previous editions of this standard and addendathereto, which have been approved by theAmerican National Standards Institute or itspredecessor organizations are as
23、follows:Z21.71-1981 Z21.71a-1985 Z21.71b-1989NOTE: This 1993 edition of Z21.71 incorporateschanges to the 1981 edition of Z21.71, andaddenda thereto. Changes, other thaneditorial, are denoted by a vertical line inthe margin.iiACCREDITED STANDARDS COMMITTEE Z21HOWARD I. FORMAN, ChairmanTHEODORE C. LE
24、MOFF, Vice ChairmanALLEN J. CALLAHAN, Administrative Secretary (Non-Voting)REPRESENTING AIR-CONDITIONINGCONTRACTORS OF AMERICA:James P. NorrisREPRESENTING AMERICAN GAS ASSOCIATION:Charles D. ApplequistMichael E. GriffinRichard L. HendricksJohn R. PeakJack D. ReaBilly R. WareREPRESENTING AMERICAN HOM
25、EECONOMICS ASSOCIATION:Frances GaileyREPRESENTING AMERICAN INSURANCESERVICES GROUP, INC.:Wallace D. MalmstedtREPRESENTING AMERICAN PUBLIC GASASSOCIATION:Robert S. CaveREPRESENTING ASSOCIATION OF HOMEAPPLIANCE MANUFACTURERS:Earl T. RhinehartREPRESENTING THE CANADIAN GASASSOCIATION:Kenneth BalesKevin
26、Campbell (Alternate)REPRESENTING CONSUMERS UNION:George PapritzREPRESENTING FACTORY MUTUAL SYSTEM:Armand V. BrandaoREPRESENTING GAS APPLIANCEMANUFACTURERS ASSOCIATION, INC.:W. C. ArndtDaniel J. CancliniAlbert B. ChamberlainWilliam E. DaltonJ. R. KatchkaJames MullenErnest WenczlREPRESENTING GENERAL S
27、ERVICESADMINISTRATION, FEDERAL SUPPLYSERVICE:Dennis DavisChristopher Pollock (Alternate)INDIVIDUAL MEMBERS:Howard I. FormanR. Michael MartinREPRESENTING INTERNATIONAL ASSOCIATIONOF PLUMBING AND MECHANICAL OFFI-CIALS:Jack AllenREPRESENTING MECHANICAL CONTRACTORSASSOCIATION OF AMERICA, INC.:William C.
28、 AbernathyiiiAccredited Standards Committee Z21 MembershipREPRESENTING NATIONAL ASSOCIATIONOF PLUMBING, HEATING, COOLINGCONTRACTORS:Terrell D. MoseleyRobert Warren (Alternate)REPRESENTING NATIONAL ELECTRICALMANUFACTURERS ASSOCIATION:G. E. WillertAlan R. Anderson (Alternate)J. E. Martin (Alternate)RE
29、PRESENTING NATIONAL FIREPROTECTION ASSOCIATION:Theodore C. LemoffREPRESENTING NATIONAL PROPANEGAS ASSOCIATION:Ty V. LotzREPRESENTING NAVAL FACILITIESENGINEERING COMMAND, U.S.DEPARTMENT OF THE NAVY:Danny C. MuiW. E. Watkins (Alternate)REPRESENTING SOUTHERN BUILDINGCODE CONGRESS:(Appointment Pending)R
30、EPRESENTING UNDERWRITERSLABORATORIES INC.:E. ToomsaluW. J. Smith (Alternate)REPRESENTING U.S. CONSUMER PRODUCTSAFETY COMMISSION:(Liaison Rep.)Donald W. SwitzerREPRESENTING U.S. DEPT. OF ENERGY:(Liaison Rep.)Ernie FreemanREPRESENTING U.S. DEPT. OF HEALTHAND HUMAN SERVICES:(Liaison Rep.)(Appointment P
31、ending)REPRESENTING U.S. DEPT. OF HOUSING ANDURBAN DEVELOPMENT:(Liaison Rep.)Victor J. FerranteivSUBCOMMITTEE ON STANDARDS FORGAS APPLIANCE CONTROL DEVICESERIC G. HAMMER, ChairmanREPRESENTING GAS COMPANIES:Eric G. HammerDaryl L. HoslereBilly D. KelleyJames P. LambJohn T. MielnikJohn W. PflumForrest
32、R. SpragueREPRESENTING MANUFACTURERS:Alan R. AndersonPaul E. BeachDonald W. CoxRichard CunhaJoseph HowverJ. R. KatchkaKent A. KeeneyG. E. WillertvCONTENTSPagePART I.MCONSTRUCTION1.1 Scope 11.2 General Construction 11.3 Materials . 21.4 Operation . 21.5 Electrical Equipment and Wiring . 21.6 Instruct
33、ions . 31.7 Homeowners Information 41.8 Marking 4Exhibit A.MRecommended Procedure for Safety InspectionExhibit A.Mof an Existing Appliance Installation as aExhibit A.MPreliminary Step to Applying an AutomaticExhibit A.MIntermittent Pilot System . . . 5Exhibit B.MProcedure for Installing AutomaticExh
34、ibit B.MIntermittent Pilot Systems . . . 7Exhibit C.MWire Color Designations 9Exhibit D.MList of Reference Standards . 10PART II.MDEFINITIONS . 11APPENDIX A.MPertinent References to ANSI Y14.15 13APPENDIX B.MPreferred Graphic Symbols of Commonly Used Items,APPENDIX B.MExtracted from ANSI/IEEE Standa
35、rd 315, GraphicAPPENDIX B.MSymbols for Electrical and Electronics DiagramsAPPENDIX B.Mand Abbreviations for These Items . . . 14APPENDIX C.MTable of Conversion Factors 22viAMERICAN NATIONAL STANDARD FORAUTOMATIC INTERMITTENT PILOT IGNITIONSYSTEMS FOR FIELD INSTALLATIONPART ICONSTRUCTION1.1MSCOPE1.1.
36、1MThis standard applies to the constructionand installation procedures for newly producedautomatic intermittent pilot ignition systems (seePart II, Definitions), hereinafter referred to as“systems,” constructed entirely of new, unusedparts and materials and designed to be adapted toexisting continuo
37、us pilot burners on listed forcedair heating appliances and boilers equipped withatmospheric burners.1.1.2MThis standard does not apply to a systemfor use on appliances equipped with powerburners or to direct vent appliances.1.1.3MSystems covered by this standard shall becomprised of at least:a. Pil
38、ot igniter(s) and cable(s);b. Pilot flame sensor(s);c. Associated system control;d. Two automatic valves in series,controlling main burner gas;e. Associated system wiring; andf. Pressure regulator(s).1.2MGENERAL CONSTRUCTION1.2.1MIgnition system components shall complywith the applicable provisions
39、of the Standard forAutomatic Gas Ignition Systems and Components,ANSI Z21.20.1.2.2MAutomatic valves shall comply with theapplicable provisions of the Standard forAutomatic Valves for Gas Appliances, ANSI Z21.21.1.2.3MManual valves shall comply with theapplicable provisions of the Standard for Manual
40、lyOperated Gas Valves for Appliances, ApplianceConnector Valves and Hose End Valves, ANSIZ21.15.1.2.4MPressure regulators shall comply with theapplicable provisions of the Standard for GasAppliance Pressure Regulators, ANSI Z21.18, andshall be equipped with a vent limiting device.1.2.5MPilot gas fil
41、ters shall comply with theapplicable provisions of the Standard for Pilot GasFilters, ANSI Z21.35.1.2.6MThe construction of systems, whetherspecifically covered in this standard or not, shallbe in accordance with reasonable concepts ofsafety, substantiality and durability. Componentparts shall be we
42、ll-fitted and not show signs ofbecoming warped, bent, broken or otherwisedamaged during any of the tests specified.1.2.7MEvery part of the system shall beconstructed so that when installed in accordancewith the manufacturers instructions, it will besecure against displacement and will maintain afixe
43、d relationship between essential parts undernormal and reasonable conditions of handling andusage.1.2.8MAll parts that may be contacted duringnormal adjustment or servicing shall be free fromsharp projections or edges and projective screwends.1.2.9MThe design of the system shall be suchthat when the
44、 system is installed in accordancewith the manufacturers installation instructions,any connection to the controls of the relatedappliance shall not adversely affect the operationof that appliance.1.2.10MAll electrical equipment, wiring andaccessories supplied for use with the system shallbe submitte
45、d for examination.11.3MMATERIALSThe manufacturer shall supply evidenceacceptable to the testing agency that all materialshave been evaluated and found to be suitable fortheir intended usage. Test data based on ASTM orother appropriate test procedures, certifications orhistorical data may be submitte
46、d for this purpose.The evidence shall show that the materials havebeen evaluated, as appropriate for resistance tomoisture, corrosion and the effects of fuel gases,including the sulfur compounds therein, and thatnon-metallic diaphragm and seal materials aresuitably resistant to the effects of ozone.
47、1.4MOPERATION1.4.1MUnder normal operating conditions, thesequence of operation of the system when installedin accordance with the manufacturers installationinstructions shall be:a. Upon a call for heat, the pilot shall beestablished and proven before gas isallowed to flow to the main burner; andb. W
48、hen the call for heat has been satisfied,both main burner and pilot burner gasshall be shut off. The main burner gasshall be shut off by means of twoautomatic valves in series.1.4.2MWhen the pilot is not proved the systemshall provide for automatic shutoff of:a. The main burner gas; andb. The pilot
49、burner gas for use with gaseshaving a specific gravity greater than 1.0.1.4.3MIn the event of a pilot outage during anoperating cycle, the system shall provide forautomatic shutoff of main burner gas and eitheract to reestablish the pilot in 0.8 second or less, orbe provided with a mechanical or electricalinterlocking means to prevent the flow of gas tothe main burner(s) when the pilot ignition meansis energized.1.5MELECTRICAL EQUIPMENT AND WIRING1.5.1MThe provisions of this section apply to allwiring and electrical components unless otherwisespecified.Wiring to be done in the field b
