1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJune 3, 20091SUBJECT 2112OUTLINE OF INVESTIGATIONFORVENTING SYSTEMS FOR USE WITH GAS-FIRED DIRECT VENTAPPLIANCESIssue Number: 1June 3, 2009Summary of TopicsThis is the first issue of the Outline
2、of Investigation for Venting Systemsfor Use with Gas-Fired Direct Vent Appliances, Subject 2112. Theserequirements cover these types of direct vent venting systems that arenot directly dependent on the intended end-use application. This wouldreduce the amount of duplicate testing (testing done on bo
3、th theappliance and the venting system).The UL Foreword is no longer located within the UL Outline of Investigation. Forinformation concerning the use and application of the requirements contained inthis Outline of Investigation, the current version of the UL Foreword is located onULStandardsInfoNet
4、 at: http:/ 2009 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJUNE 3, 2009SUBJECT 21122No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM
5、ULCONTENTSINTRODUCTION1 Scope .42 Units of Measurement .43 Glossary .44 Components 5CONSTRUCTION5 Materials .66 Assembly 77 Joints 78 Firestop Spacers 89 Thimbles .810 Support Assembly .811 Radiation Shields 912 Vent Termination Assembly .9PERFORMANCE13 General 1014 Vertical Support Test 1115 Streng
6、th Tests 1115.1 Impact test 1115.2 Vent termination load test .1415.3 Longitudinal force test 1415.4 Load test for vent elbows 1515.5 Vent joint load test .1516 Wind Load Test 1616.1 Test on roof assemblies .1616.2 Test on lateral supports .1717 Rain Test 2018 Vent Sag Test for Horizontal Installati
7、ons 2319 Joint Sealing Compound Test 2620 Test Conditions for Markings .2720.1 Air oven-aging test .2720.2 Humidity test .2720.3 Unusual-condition exposure test .27MARKING21 General 2722 Permanency of Marking .28INSTRUCTIONS23 Installation and Maintenance Instructions 29Standards for ComponentsA1JUN
8、E 3, 2009 SUBJECT 2112 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 These requirements cover venting systems intended for venting direct vented gas-fired appliancesthat comply with ANSI Z21 series Standards. Venting
9、systems covered by these requirements areintended to be used with direct vented gas-fired appliances that have been installed in accordance withthe National Fuel Gas Code, NFPA 54 and with Codes such as the International Mechanical Code,International Residential Code, Uniform Mechanical Code, and lo
10、cal Codes.1.2 The requirements covered by this Outline are intended to address the structural integrity supportingmeans, rain effects, and corrosion effects of the venting system. For wind effects, leakage, and clearanceto combustible construction the appliance standard requirements shall be applied
11、.1.3 These requirements do not cover venting systems intended for use with Category II, III or IVappliances.2 Units of Measurement2.1 When a value for measurement is followed by a value in other units in parentheses, the second valuemay be only approximate. The first stated value is the requirement.
12、3 Glossary3.1 For the purpose of this Outline the following definitions apply.3.2 APPLIANCE Utilization equipment, normally built in standardized sizes or types, that is installedor connected as a unit to perform one or more functions, such as clothes washing, air conditioning, foodmixing, cooking,
13、heating, and refrigerating.3.3 BTU Abbreviation for British Thermal Unit. The quantity of heat required to raise the temperatureof 1 lb of water 1F.3.4 COMBUSTIBLE MATERIAL Material made of or surfaced with wood, compressed paper, plantfibers, or other material that will ignite and burn as applied t
14、o materials adjacent to or in contact withheat-producing appliances, vent connectors and chimney connectors. Such material shall be determinedto be combustible even though flame proofed, fire retardant treated or plastered.3.5 DIRECT VENT APPLIANCES A system consisting of an appliance, combustion ai
15、r and flue gasconnections between the appliance and the outdoor atmosphere, and a vent cap constructed so all airfor combustion is obtained from the outdoor atmosphere and all flue gases are discharged to theoutdoor atmosphere.3.6 FLUE GAS Products of combustion plus excess air in appliance flues.3.
16、7 NONCOMBUSTIBLE MATERIAL A material that, in the form in which it is used and under theconditions of normal use does not ignite, burn, support combustion, or release flammable vapors whensubjected to fire or heat.3.8 OFFSET VENT A venting system that incorporates elbows.3.9 PRODUCT All venting syst
17、ems or any part thereof covered by these requirements unlessspecifically noted otherwise.JUNE 3, 2009SUBJECT 21124UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL3.10 RADIATION SHIELD An integral part of a firestop-spacer or support assembly i
18、ntended to limitthe temperature rise of combustible construction.3.11 TEMPERATURE RATING The maximum use temperature specified by the vent manufacturerfor which the venting system is intended.3.12 THIMBLE The part of the venting system that is intended to provide a means for routing theventing syste
19、m through a combustible wall in a horizontal installation.3.13 VENT GAS CONDUIT The parts of a venting system that is a continuous conveyer of thegases from the appliance outlet to the outside atmosphere.3.14 VENT TERMINATION CAP The parts of a venting system that terminates exterior to thebuilding
20、and is intended to resist the entrance of debris and rain into the vent gas conduit.3.15 VENTING SYSTEM A complete assembly, external of an appliance, comprised of all field-installed component parts required to convey vent gas products from an appliance to the outsideatmosphere.4 Components4.1 Exce
21、pt as indicated in 4.2, a component of a product covered by this Outline shall comply with therequirements for that component. See Appendix A for a list of standards covering components generallyused in the products covered by this Outline.4.2 A component is not required to comply with the specific
22、requirement that:a) Involves a feature or characteristic not required in the application of the component in theproduct covered by this Outline; orb) Is superseded by a requirement in this Outline.4.3 A component shall be used in accordance with its rating established for the intended conditions ofu
23、se.4.4 Specific components are incomplete in construction features or restricted in performance capabilities.Such components are intended for use only under limited conditions, such as certain temperatures notexceeding specified limits, and shall be used only under those specific conditions.JUNE 3,
24、2009 SUBJECT 2112 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONSTRUCTION5 Materials5.1 A direct-vent venting part shall be made of noncombustible corrosion-resistant materials. Metals shallnot be used in combinations that results in gal
25、vanic action at any location within the assembly.5.2 The minimum thickness of sheet metal, including any coatings, shall be as specified in Table 5.1,unless otherwise specified.5.3 Aluminum alloys containing more than 1.0 percent magnesium shall not be used when the reflectivityof the material is ut
26、ilized to reduce the risk of fire.Table 5.1Minimum metal thicknessMetal Inch (mm)Aluminum alloys (1100, 3003) inner pipe 0.012 (0.30)Aluminum alloys (1100, 3003) other thaninner pipe steel0.016 (0.41)Galvanized steel (G90 coating class) 0.018 (0.46)Aluminized-coated steel 0.40 ounces persquare foot
27、(0.12 kg/m2)0.018 (0.46)Stainless steel (Type 430) 0.012 (0.30)5.4 A flue-gas conveying conduit shall be of a material having durability and resistance to corrosion andheat equivalent to that of Type 1100 aluminum, Series 300 or Types 430 and 446 stainless steel, orporcelain-coated steel complying w
28、ith the requirements contained herein. Except as noted in 5.5, parts incontact with flue gases or flue gas-air mixtures, or subject to condensation, shall be of material havingdurability and resistance to corrosion and heat equivalent to Type 1100 aluminum or Series 300 or Types430 and 446 stainless
29、 steel.5.5 An outer casing or other structural part shall be of stainless steel, galvanized steel, or aluminized steelwhen any of the following apply:a) Deterioration or corrosion of the part results in collapse of the venting system or otherwiseincreases the risk of injury to persons;b) The part ad
30、joins firestopping material; orc) The part is subject to condensation.Exception: This requirement does not apply to the flue gas conveying conduit or other parts in contactwith flue-gas or flue-gas air mixtures. See 5.4.5.6 Galvanized steel used for outer casings, structural parts, firestoppings, or
31、 other components orsubassemblies shall have a zinc-coating complying with the coating designation G90 in the StandardSpecification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by theHot-Dip Process, ASTM A653 with not less than 40 percent of the zinc on any sid
32、e, based on theminimum single spot test in ASTM A653. The weight of zinc coating shall be established in accordanceJUNE 3, 2009SUBJECT 21126UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULwith the Standard Test Method for Weight Mass of Coatin
33、g on Iron and Steel Articles with Zinc orZinc-Alloy Coatings, ASTM A90. Aluminum coated steel shall be of Type T1-40 (regular) 0.40 ounce persquare foot (0.12 kg/m2).5.7 Metallic materials which are coated shall be free of sharp edges, burrs or protrusions which damagemating parts in a manner so as
34、to reduce the thickness of the coating.5.8 An adhesive or cement used to attach such materials together shall retain its adhesive qualities at anyelevated temperature the adhesive attains when tested in accordance with these requirements and at 0F(-18C).6 Assembly6.1 A venting system shall consist o
35、f all the essential parts required for the intended installation. Eachventing system part shall be constructed for assembly as intended without requiring alteration, cutting,threading, drilling, welding or similar tasks.6.2 Two or more parts of a venting system that bear a definite relationship to e
36、ach other in the intendedapplication shall:a) Be arranged and constructed in order for them to be incorporated into the completeassembly without alteration or alignment, and only in the correct relationship with each other; orb) Be assembled and shipped from the factory as one unit.6.3 Each individu
37、al part, such as a vent pipe system, elbow, vent cap, firestop-spacer, or tee shall becompletely assembled by the manufacturer at the factory.6.4 A venting system shall not void the firestopping required between spaces of a building when theassembly is installed in accordance with the manufacturers
38、installation instructions.6.5 A venting system shall not take air from an occupied space and exhaust such air to the outside of abuilding for cooling purposes.7 Joints7.1 Parts of a venting system shall be joined and secured, so they do not disengage when tested inaccordance with these requirements.
39、7.2 When cement, joining compounds, tape, screws, or similar materials are required for sealing ventjoints, they shall be provided or specified in the manufacturers installation instructions and be readilyavailable. Joint compounds and tape shall be resistant to deterioration due to aging and temper
40、aturesanticipated during use of a venting system. See Joint Sealing Compound Test, Section 19.7.3 A joint shall not retain condensate or permit condensate to flow from the interior to the exterior of thevent gas conduit.JUNE 3, 2009 SUBJECT 2112 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER RE
41、PRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL7.4 A joint shall not reduce the cross-sectional area of the vent gas conduit.8 Firestop Spacers8.1 A venting system intended for vertical installation within a trade size 2 by 4 inches nominal 1-1/2 by3-1/2 inches (38 by 89 mm) or a trade size 2 b
42、y 6 inches nominal 1-1/2 by 5-1/2 inches (38 by 140 mm)stud space, with other than zero clearance, shall be provided with ceiling plate spacers constructed tolocate the venting system centrally in the stud space.8.2 A ceiling-plate spacer shall constitute a complete firestop.8.3 A spacer shall have
43、enough strength and bearing surface to maintain the required clearance fromventing system parts to joists, ceiling and floor material, and the inner surface of walls.8.4 A firestop shall provide complete firestopping when the assembly is installed in a framed joistopening, or through a stud space, t
44、hat is 1/2 inches (13 mm) greater on each side than the opening forwhich the space is intended. A spacer shall provide for continuous interference around the perimeter ofthe construction for a height of not less than 1 inch (25 mm). The inside diameter of the firestop openingshall not be more than 1
45、/8 inch (3.2 mm) greater than the outside diameter of the venting system, eitherat the firestop or at the outside diameter of the venting system, excluding vent joints and raisedprojections.8.5 During these tests, temperatures are to be determined with fireplace screens withdrawn (open).9 Thimbles9.
46、1 A venting system intended for horizontal installation shall be provided with a thimble constructed toenable the venting system to penetrate a vertical wall unless the venting system is tested at zeroclearance to combustible construction.9.2 A thimble shall have enough strength and bearing surface
47、to maintain the required clearance from theventing system parts to the wall studs and inner surfaces of walls.10 Support Assembly10.1 A support assembly, when required, shall establish and maintain the minimum required clearancebetween a venting system and combustible construction. A support for ins
48、tallation in a joist area shallconstitute a complete firestop when tested in accordance with these requirements.10.2 A support assembly shall sustain a load equivalent to four times the weight imposed upon it by allthe venting system parts it is intended to support. See Vertical Support Test, Sectio
49、n 14.10.3 A support assembly intended to be secured by nails or screws shall be arranged so that the load onsuch holding means is a shear or compressive load.10.4 A venting system intended for exterior installation shall be provided with support assemblies.JUNE 3, 2009SUBJECT 21128UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL10.5 An offset vent shall be supported at or immediately above the vertical return elbow at the first floor
