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// CODE SNIPPET

Section G2428 (504) Sizing of Category I Appliance Venting Systems

Residential Code 2018 of Kansas > 24 Fuel Gas > G2428 (504) Sizing of Category I Appliance Venting Systems
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G2428.1 (504.1) Definitions

The following definitions apply to the tables in this section.
APPLIANCE CATEGORIZED VENT DIAMETER/AREA. The minimum vent area/diameter permissible for Category I appliances to maintain a nonpositive vent static pressure when tested in accordance with nationally recognized standards.
FAN-ASSISTED COMBUSTION SYSTEM. An appliance equipped with an integral mechanical means to either draw or force products of combustion through the combustion chamber or heat exchanger.
FAN Min. The minimum input rating of a Category I fan-assisted appliance attached to a vent or connector.
FAN Max. The maximum input rating of a Category I fan-assisted appliance attached to a vent or connector.
NAT Max. The maximum input rating of a Category I draft-hood-equipped appliance attached to a vent or connector.
FAN + FAN. The maximum combined appliance input rating of two or more Category I fan-assisted appliances attached to the common vent.
FAN + NAT. The maximum combined appliance input rating of one or more Category I fan-assisted appliances and one or more Category I draft-hood-equipped appliances attached to the common vent.
NA. Vent configuration is not allowed due to potential for condensate formation or pressurization of the venting system, or not applicable due to physical or geometric restraints.
NAT + NAT.The maximum combined appliance input rating of two or more Category I draft-hood-equipped appliances attached to the common vent.

G2428.2 (504.2) Application of Single-Appliance Vent Tables G2428.2(1) and G2428.2(2)

The application of Tables G2428.2(1) and G2428.2(2) shall be subject to the requirements of Sections G2428.2.1 through G2428.2.17.
TABLE G2428.2(1) [504.2(1)]
TYPE B DOUBLE-WALL GAS VENT
Number of AppliancesSingle
Appliance TypeCategory I
Appliance Vent ConnectionConnected directly to vent
HEIGHT
(H)
(feet)
LATERAL
(L)
(feet)
VENT DIAMETER—(D) inches
3456789
APPLIANCE INPUT RATING IN THOUSANDS OF BTU/H
FANNATFANNATFANNATFANNATFANNATFANNATFANNAT
MinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMax
600784601528602511410375205052428506983700897470
21351361897672715710532232157443212175342528563543370
42149343094643915310350227153663162117941927993536362
625463236916147149100592231497831020593413273110530354
8008450016594027615504152350583320078041501,006537
212574016109752517812028263180423652475048332260619418
523533832103714217111553255173703562378347331399607407
828493539986651164109642471658434722799463303117596396
100088530175100029516604472550631345084745001,096585
212614217118812319412926289195404022734853335557684457
523574032113774118712452280188683922638152234695671446
103051364110470541761156726717588376245104504330122651427
150094580191112032718705022850716390097052501,263682
211694815136932022615022339225384753164563341453815544
522654530130873921914249330217644633007662040390800529
10295941401218251206135643152088444528899600386116777507
153553374811276611951287630119898429275115580373134755491
20009761020211903492020540307077643001,05757501,384752
2107551141491001825016620377249335313464171147050917612
521714829143963824216047367241625193377369746086902599
10286444381338950229150623512288149932195675443112877576
153458404612484592171427333721794481308111654427129853557
2048523555116786920613484322206107464295125634410145830537
300010064021312803742200587336085347501,17365001,548855
2981561316611214283185184322802761339433826535421,072700
52177542816010836275176454212735860038569811524821,055688
1027705037150102482621715940526177580371917885071071,028668
153364NA44141965724916370389249905603571057654901241,002648
205658NA53132906623715480374237102542343119743473139977628
30NANANA73113NA88214NA104346219131507321149702444171929594
500010167021613403972320633363093251801,29770801,730952
2886611118312214320206154973142271544526975615331,276813
52082NA2717711935312200434873085570243865960605771,259798
102676NA35168114452991905647129873681426869355891011,230773
155970NA42158NA5428718066455288856624131009115721171,203747
20NANANA50149NA6327516976440278976424011138885561311,176722
30NANANA69131NA84250NA994102591236053761418445221611,125670
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 British thermal unit per hour = 0.2931 W.
TABLE G2428.2(2) [504.2(2)]
TYPE B DOUBLE-WALL GAS VENT
Number of AppliancesSingle
Appliance TypeCategory I
Appliance Vent ConnectionSingle-wall metal connector
HEIGHT
(H)
(feet)
LATERAL
(L)
(feet)
VENT DIAMETER—(D) inches
34567891012
APPLIANCE INPUT RATING IN THOUSANDS OF BTU/H
FANNATFANNATFANNATFANNATFANNATFANNATFANNATFANNATFANNAT
MinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMax
603877455915185852491401263732041655222842116953692678944693711,1185695371,639849
239513660966685156104123231156159320213201423284251541368347673453498979648
4NANA33749263102152102146225152187313208237416277295533360409664443584971638
6NANA3183896011414799163220148207307203263409271327526352449656433638962627
803783505816493832731541234122341615803192067774142581,0025363601,2576585211,852967
23956395910875831761191212611791553632461974823212466174173397685134861,120743
5NANA3777102691071681141512521711933522352454703113056044044187545005981,104730
8NANA339095641221611071752431632233422252804583003445913924707404866651,089715
1003787535717499822931651204442541586283442028444492531,0935843511,3737185072,0311,057
23961415911780821931281192871941534002721935313542426814563328495594751,242848
552563976111761051851221482771861903882612415183442996674434098345445841,224825
10NANA3497100681321711121882611712373692412964973253636434234928085206881,194788
15036935756190111803251861164992831537133881959665232441,2596813361,5918384882,3741,237
23869475713693802251491153372241484733141876314132328125433191,0156734571,491983
551634475128861022161401443262171824592982316164002877955263929976575621,469963
10NANA3995116791282011311823082032284382842845923813497685014709666286641,433928
15NANANANANA721581861242202901922724182693345683674047424845409376017501,399894
20035966054200118783462011145373061497724281901,0535732381,3797503261,7519274732,6311,346
23774505614899782481651133752481445283441827084682279146113091,1467544431,6891,098
550684773140941002391581413632391785143342246924572798965963811,1267345471,6651,074
10NANA4193129861252231461773442242224913162776664373398665704571,0927026461,6261,037
15NANANANANA801552081362163252102644693013256404193938385495261,0606777301,5871,005
20NANANANANANA1861921262543061963094482853746164004488105265921,0286518081,550973
30034996353211127763722191105843341448494721841,1686472291,5428523121,9711,0564542,9961,545
237805655164111762811831094292791396103921758235332191,0696982961,3468634241,9991,308
549745272157106982711731364172711715953822158065212691,0496843661,3248465241,9711,283
10NANANA91144981222551681713972572135703672657775013271,0176624401,2878216201,9271,234
15NANANA115131NA1512391572083772422555473493127504813799856385071,2517947021,8841,205
20NANANANANANA181223NA2463572282985243333607234614339556155701,2167687801,8411,166
30NANANANANANANANANANANANA3894773054616704265418955747041,1477209371,7591,101
50033996651213133733942301056293611389285151761,2927042201,7249482952,2231,1894283,4321,818
236846153181121733182051044953121337124431689716132091,2738112801,6151,0074012,4261,509
54880NA70174117943081981314823051646964352049536022571,2527953471,5919914962,3961,490
10NANANA89160NA1182921861624612922036714202539235833131,2177654181,5519635892,3471,455
15NANANA112148NA1452751741994412802446464052998945623631,1837364811,5129346682,2991,421
20NANANANANANA176257NA2364202672856223893458665434151,1507085441,4739067412,2511,387
30NANANANANANANANANA315376NA373573NA4428095025211,0866496741,3998488922,1591,318
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 British thermal unit per hour = 0.2931 W.

G2428.2.1 (504.2.1) Vent Obstructions

These venting tables shall not be used where obstructions, as described in Section G2427.15, are installed in the venting system. The installation of vents serving listed appliances with vent dampers shall be in accordance with the appliance manufacturer's instructions or in accordance with the following:
  1. The maximum capacity of the vent system shall be determined using the "NAT Max" column.
  2. The minimum capacity shall be determined as if the appliance were a fan-assisted appliance, using the "FAN Min" column to determine the minimum capacity of the vent system. Where the corresponding "FAN Min" is "NA," the vent configuration shall not be permitted and an alternative venting configuration shall be utilized.

G2428.2.2 (504.2.2) Minimum Size

Where the vent size determined from the tables is smaller than the appliance draft hood outlet or flue collar, the smaller size shall be permitted to be used provided that all of the following requirements are met:
  1. The total vent height (H) is not less than 10 feet (3048 mm).
  2. Vents for appliance draft hood outlets or flue collars 12 inches (305 mm) in diameter or smaller are not reduced more than one table size.
  3. Vents for appliance draft hood outlets or flue collars larger than 12 inches (305 mm) in diameter are not reduced more than two table sizes.
  4. The maximum capacity listed in the tables for a fan-assisted appliance is reduced by 10 percent (0.90 × maximum table capacity).
  5. The draft hood outlet is greater than 4 inches (102 mm) in diameter. Do not connect a 3-inch-diameter (76 mm) vent to a 4-inch-diameter (102 mm) draft hood outlet. This provision shall not apply to fan-assisted appliances.

G2428.2.3 (504.2.3) Vent Offsets

Single-appliance venting configurations with zero (0) lateral lengths in Tables G2428.2(1) and G2428.2(2) shall not have elbows in the venting system. Single-appliance venting configurations with lateral lengths include two 90-degree (1.57 rad) elbows. For each additional elbow up to and including 45 degrees (0.79 rad), the maximum capacity listed in the venting tables shall be reduced by 5 percent. For each additional elbow greater than 45 degrees (0.79 rad) up to and including 90 degrees (1.57 rad), the maximum capacity listed in the venting tables shall be reduced by 10 percent. Where multiple offsets occur in a vent, the total lateral length of all offsets combined shall not exceed that specified in Tables G2428.2(1) and G2428.2(2).

G2428.2.4 (504.2.4) Zero Lateral

Zero (0) lateral (L) shall apply only to a straight vertical vent attached to a top outlet draft hood or flue collar.

G2428.2.5 (504.2.5) High-Altitude Installations

Sea-level input ratings shall be used when determining maximum capacity for high-altitude installation. Actual input, derated for altitude, shall be used for determining minimum capacity for high-altitude installation.

G2428.2.6 (504.2.6) Multiple Input Rate Appliances

For appliances with more than one input rate, the minimum vent capacity (FAN Min) determined from the tables shall be less than the lowest appliance input rating, and the maximum vent capacity (FAN Max/NAT Max) determined from the tables shall be greater than the highest appliance rating input.

G2428.2.7 (504.2.7) Liner System Sizing and Connections

Listed corrugated metallic chimney liner systems in masonry chimneys shall be sized by using Table G2428.2(1) or G2428.2(2) for Type B vents with the maximum capacity reduced by 20 percent (0.80 × maximum capacity) and the minimum capacity as shown in Table G2428.2(1) or G2428.2(2). Corrugated metallic liner systems installed with bends or offsets shall have their maximum capacity further reduced in accordance with Section G2428.2.3. The 20-percent reduction for corrugated metallic chimney liner systems includes an allowance for one long-radius 90-degree (1.57 rad) turn at the bottom of the liner.
Connections between chimney liners and listed double-wall connectors shall be made with listed adapters designed for such purpose.

G2428.2.8 (504.2.8) Vent Area and Diameter

Where the vertical vent has a larger diameter than the vent connector, the vertical vent diameter shall be used to determine the minimum vent capacity, and the connector diameter shall be used to determine the maximum vent capacity. The flow area of the vertical vent shall not exceed seven times the flow area of the listed appliance categorized vent area, flue collar area, or draft hood outlet area unless designed in accordance with approved engineering methods.

G2428.2.9 (504.2.9) Chimney and Vent Locations

Tables G2428.2(1) and G2428.2(2) shall be used only for chimneys and vents not exposed to the outdoors below the roof line. A Type B vent or listed chimney lining system passing through an unused masonry chimney flue shall not be considered to be exposed to the outdoors. Where vents extend outdoors above the roof more than 5 feet (1524 mm) higher than required by Figure G2427.6.4, and where vents terminate in accordance with Section G2427.6.4, Item 2, the outdoor portion of the vent shall be enclosed as required by this section for vents not considered to be exposed to the outdoors or such venting system shall be engineered. A Type B vent shall not be considered to be exposed to the outdoors where it passes through an unventilated enclosure or chase insulated to a value of not less than R-8.

G2428.2.10 (504.2.10) Corrugated Vent Connector Size

Corrugated vent connectors shall be not smaller than the listed appliance categorized vent diameter, flue collar diameter, or draft hood outlet diameter.

G2428.2.11 (504.2.11) Vent Connector Size Limitation

Vent connectors shall not be increased in size more than two sizes greater than the listed appliance categorized vent diameter, flue collar diameter or draft hood outlet diameter.

G2428.2.12 (504.2.12) Component Commingling

In a single run of vent or vent connector, different diameters and types of vent and connector components shall be permitted to be used, provided that all such sizes and types are permitted by the tables.

G2428.2.13 (504.2.13) Draft Hood Conversion Accessories

Draft hood conversion accessories for use with masonry chimneys venting listed Category I fan-assisted appliances shall be listed and installed in accordance with the manufacturer's instructions for such listed accessories.

G2428.2.14 (504.2.14) Table Interpolation

Interpolation shall be permitted in calculating capacities for vent dimensions that fall between the table entries.

G2428.2.15 (504.2.15) Extrapolation Prohibited

Extrapolation beyond the table entries shall not be permitted.

G2428.2.16 (504.2.16) Engineering Calculations

For vent heights less than 6 feet (1829 mm) and greater than shown in the tables, engineering methods shall be used to calculate vent capacities.

G2428.2.17 (504.2.17) Height Entries

Where the actual height of a vent falls between entries in the height column of the applicable table in Tables G2428.2(1) and G2428.2(2), either interpolation shall be used or the lower appliance input rating shown in the table entries shall be used for FAN Max and NAT Max column values and the higher appliance input rating shall be used for the FAN Min column values.

G2428.3 (504.3) Application of Multiple Appliance Vent Tables G2428.3(1) Through G2428.3(4)

The application of Tables G2428.3(1) through G2428.3(4) shall be subject to the requirements of Sections G2428.3.1 through G2428.3.24.
TABLE G2428.3(1) [504.3(1)]
TYPE B DOUBLE-WALL VENT
Number of AppliancesTwo or more
Appliances TypeCategory I
Appliances Vent ConnectionType B double-wall connector
VENT CONNECTOR CAPACITY
VENT
HEIGHT

(H)
(feet)
CONNECTOR
RISE
(R)
(feet)
TYPE B DOUBLE-WALL VENT AND CONNECTOR DIAMETER—(D) inches
345678910
APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU/H
FANNATFANNATFANNATFANNATFANNATFANNATFANNATFANNAT
MinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMax
612237263566464610672581641047722514292296185109376237128466289
22341313775554812186601831247925316895333220112424282131526345
32444353881624913296621991398227518997363248114463317134575386
8122402735724849114766417610984243148100320194118408248138507303
223443236805751128906619512986269175103356230121454294141564358
3244736378764531391016721014588290198105384258123492330143612402
10122432834785049123786518911389257154106341200125436257146542314
223473336865951136936720613491282182109374238128479305149596372
3245037379267521461046922015094303205111402268131515342152642417
15121503033895347142836422012088298163110389214134493273162609333
222533535966349153996623514291320193112419253137532323165658394
32455403610271511631116824816093339218115445286140565365167700444
20121543133995646157876224612586334171107436224131552285158681347
22257373410566481671046425914989354202110463265134587339161725414
32360423511074501761166627116891371228113486300137618383164764466
301206233311135945181936028813483391182103512238125649305151802372
22164393311870471901106229915885408215105535282129679360155840439
32266443412379481981246430917888423242108555317132706405158874494
COMMON VENT CAPACITY
VENT
HEIGHT

(H)
(feet)
TYPE B DOUBLE-WALL COMMON VENT DIAMETER (D)—inches
45678910
COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU/H
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
6928165140116103204161147309248200404314260547434335672520410
81019073155129114224178163339275223444348290602480378740577465
101109779169141124243194178367299242477377315649522405800627495
1512511291195164144283228206427352280556444365753612465924733565
201361231022151831603142552294753943106214994058426885231,035826640
301521381182442101853612972665474593607205854709798086051,209975740
501671531342792442144213533106415474238547065501,1649777051,4511,188860
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 British thermal unit per hour = 0.2931 W.
TABLE G2428.3(2) [504.3(2)]
TYPE B DOUBLE-WALL VENT
Number of AppliancesTwo or more
Appliances TypeCategory I
Appliances Vent ConnectionSingle-wall metal connector
VENT CONNECTOR CAPACITY
VENT
HEIGHT

(H)
(feet)
CONNECTOR
RISE
(R)
(feet)
SINGLE-WALL METAL VENT CONNECTOR DIAMETER—(D) inches
345678910
APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU/H
FANNATFANNATFANNATFANNATFANNATFANNATFANNATFANNAT
MinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMax
61NANA26NANA46NANA71NANA102207223140262293183325373234447463286
2NANA31NANA55NANA85168182123215251167271331219334422281458524344
3NANA34NANA6212113195175198138222273188279361247344462316468574385
81NANA27NANA48NANA75NANA106226240145285316191352403244481502299
2NANA32NANA5712512689184193127234266173293353228360450292492560355
3NANA35NANA64130138100191208144241287197302381256370489328501609400
101NANA28NANA5011912177182186110240253150302335196372429252506534308
2NANA3384855912413491189203132248278183311369235381473302517589368
3NANA36899167129144102197217148257299203320398265391511339528637413
151NANA2979875211613881177214116238291158312380208397482266556596324
2NANA3483946212115097185230138246314189321411248407522317568646387
3NANA398710070127160109193243157255333215331438281418557360579690437
20149563078975411515284175238120233325165306425217390538276546664336
25259368210364120163101182252144243346197317453259400574331558709403
35562408710772125172113190264164252363223326476294412607375570750457
301476031771105711217589169278129226380175296497230378630294528779358
25162378111567117185106177290152236397208307521274389662349541819425
35464428511976122193120185300172244412235316542309400690394555855482
COMMON VENT CAPACITY
VENT
HEIGHT

(H)
(feet)
TYPE B DOUBLE-WALL COMMON VENT DIAMETER—(D) inches
45678910
COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU/H
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
6NA7864NA11399200158144304244196398310257541429332665515407
8NA8771NA126111218173159331269218436342285592473373730569460
10NA9476163137120237189174357292236467369309638512398787617487
1512110888189159140275221200416343274544434357738599456905718553
20131118982081771563052472234633833026064873958246735121,013808626
301451321132362021803502862575334463497035704599587905931,183952723
501591451282682332084063372966225294108336865351,1399546891,4181,157838
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 British thermal unit per hour = 0.2931 W.
TABLE G2428.3(3) [504.3(3)]
MASONRY CHIMNEY
Number of AppliancesTwo or more
Appliances TypeCategory I
Appliances Vent ConnectionType B double-wall connector
VENT CONNECTOR CAPACITY
VENT
HEIGHT

(H)
(feet)
CONNECTOR
RISE

(R)
(feet)
TYPE B DOUBLE-WALL VENT CONNECTOR DIAMETER—(D) inches
345678910
APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU/H
FANNATFANNATFANNATFANNATFANNATFANNATFANNATFANNAT
MinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMax
6124332139624052106676519410187274141104370201124479253145599319
226432841795253133856723012489324173107436232127562300148694378
327493442926155155976926214391369203109491270129633349151795439
8124392239724155117697121310594304148113414210134539267156682335
226472940875357140867324612797350179116473240137615311160776394
327523442976259159987526914599383206119517276139672358163848452
101244222388042551307174232108101324153120444216142582277165739348
2265029409354571538776261129103366184123498247145652321168825407
327553541105635817010078284148106397209126540281147705366171893463
151244823389344541547472277114100384164125511229153658297184824375
22555313910555561748974299134103419192128558260156718339187900432
326593541115645718910276319153105448215131597292159760382190960486
201245224371024653172777131311998437173123584239150752312180943397
225583139114565519091733351381014671991266252701538053541841,011452
3266335401236557204104753531571044932221296613011568513961871,067505
COMMON VENT CAPACITY
VENT
HEIGHT

(H)
(feet)
MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)
12192838506378113
COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU/H
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
6NA7425NA11946NA17871NA257103NA351143NA458188NA5822461,041853NA
8NA8028NA13053NA19382NA279119NA384163NA5012187246362781,144937408
10NA8431NA13856NA20790NA299131NA4091776065382367766863021,2261,010454
15NANA36NA15267NA233106NA3341525234672126826112838747813651,3741,156546
20NANA41NANA75NA250122NA3681725655082437426683259558584191,5131,286648
30NANANANANANANA270137NA4041986155642788167473811,0629694961,7021,473749
50NANANANANANANANANANANANANA6203288798314611,1651,0896061,9051,692922
For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2, 1 foot = 304.8 mm, 1 British thermal unit per hour = 0.2931 W.
TABLE G2428.3(4) [504.3(4)]
MASONRY CHIMNEY
Number of AppliancesTwo or more
Appliances TypeCategory I
Appliances Vent ConnectionSingle-wall connector
VENT CONNECTOR CAPACITY
VENT
HEIGHT

(H)
(feet)
CONNECTOR
RISE

(R)
(feet)
SINGLE-WALL METAL VENT CONNECTOR DIAMETER (D)—inches
345678910
APPLIANCE INPUT RATING LIMITS IN THOUSANDS OF BTU/H
FANNATFANNATFANNATFANNATFANNATFANNATFANNATFANNAT
MinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMaxMinMaxMax
61NANA21NANA39NANA66179191100231271140292366200362474252499594316
2NANA28NANA52NANA84186227123239321172301432231373557299509696376
3NANA34NANA6113415397193258142247365202309491269381634348519793437
81NANA21NANA40NANA68195208103250298146313407207387530263529672331
2NANA28NANA5213713985202240125258343177323465238397607309540766391
3NANA34NANA6214315698210264145266376205332509274407663356551838450
101NANA22NANA4113015170202225106267316151333434213410571273558727343
2NANA29NANA5313615086210255128276358181343489244420640317569813403
3NANA34971026214316699217277147284389207352530279430694363580880459
151NANA23NANA4312915173199271112268376161349502225445646291623808366
2NANA30921035413517088207295132277411189359548256456706334634884424
3NANA349611263141185101215315151286439213368586289466755378646945479
201NANA2387994512816776197303117265425169345569235439734306614921347
2NANA30911115513418590205325136274455195355610266450787348627986443
3NANA3596119641401991032133431542824812193656442984618313916391,042496
COMMON VENT CAPACITY
VENT
HEIGHT

(H)
(feet)
MINIMUM INTERNAL AREA OF MASONRY CHIMNEY FLUE (square inches)
12192838506378113
COMBINED APPLIANCE INPUT RATING IN THOUSANDS OF BTU/H
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
FAN
+FAN
FAN
+NAT
NAT
+NAT
6NANA25NA11845NA17671NA255102NA348142NA455187NA579245NA846NA
8NANA28NA12852NA19081NA276118NA380162NA497217NA6332771,136928405
10NANA31NA13656NA20589NA295129NA405175NA5322341716803001,2161,000450
15NANA36NANA66NA230105NA335150NA4002106776022808667723601,3591,139540
20NANANANANA74NA247120NA362170NA5032407656613219478494151,4951,264640
30NANANANANANANANA135NA398195NA5582758087393771,0529574901,6821,447740
50NANANANANANANANANANANANANA612325NA8214561,1521,0766001,8791,672910
For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2, 1 foot = 304.8 mm, 1 British thermal unit per hour = 0.2931 W.
SEE MORE

Related Code Sections


Section G2428 Fuel Gas, (504) Sizing of Category I Appliance Venting Systems
permissible for Category I appliances to maintain a nonpositive vent static pressure when tested in accordance with nationally recognized standards. FAN ...
Residential Code 2018 of Kansas > 24 Fuel Gas > G2428 (504) Sizing of Category I Appliance Venting Systems
G2428.2.13 Fuel Gas, (504.2.13) Draft Hood Conversion Accessories
Draft hood conversion accessories for use with masonry chimneys venting listed Category I fan-assisted appliances shall be listed and installed ...
Residential Code 2018 of Kansas > 24 Fuel Gas > G2428 (504) Sizing of Category I Appliance Venting Systems > G2428.2 (504.2) Application of Single-Appliance Vent Tables G2428.2(1) and G2428.2(2) > G2428.2.13 (504.2.13) Draft Hood Conversion Accessories
G2428.2.7 Fuel Gas, (504.2.7) Liner System Sizing and Connections
Listed corrugated metallic chimney liner systems in masonry chimneys shall be sized by using Table G2428.2(1) or G2428.2(2) for Type B vents ...
Residential Code 2018 of Kansas > 24 Fuel Gas > G2428 (504) Sizing of Category I Appliance Venting Systems > G2428.2 (504.2) Application of Single-Appliance Vent Tables G2428.2(1) and G2428.2(2) > G2428.2.7 (504.2.7) Liner System Sizing and Connections
G2428.2.10 Fuel Gas, (504.2.10) Corrugated Vent Connector Size
Corrugated vent connectors shall be not smaller than the listed appliance categorized vent diameter, flue collar diameter, or draft hood ...
Residential Code 2018 of Kansas > 24 Fuel Gas > G2428 (504) Sizing of Category I Appliance Venting Systems > G2428.2 (504.2) Application of Single-Appliance Vent Tables G2428.2(1) and G2428.2(2) > G2428.2.10 (504.2.10) Corrugated Vent Connector Size
G2428.2.11 Fuel Gas, (504.2.11) Vent Connector Size Limitation
Vent connectors shall not be increased in size more than two sizes greater than the listed appliance categorized vent diameter, flue collar ...
Residential Code 2018 of Kansas > 24 Fuel Gas > G2428 (504) Sizing of Category I Appliance Venting Systems > G2428.2 (504.2) Application of Single-Appliance Vent Tables G2428.2(1) and G2428.2(2) > G2428.2.11 (504.2.11) Vent Connector Size Limitation
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