Page 169 - 2018_IFGC

APPENDIX B

Example: Manifolded Common Vent Connector LM shall be not greater than
18 times the common vent connector manifold inside diameter; i.e., a 4-inch
(102 mm) inside diameter common vent connector manifold shall not exceed Vent connector size depends on: Common vent size depends on:
72 inches (1829 mm) in length (see Section 504.3.4). • Input • Combined inputs
Note: This is an illustration of a typical manifolded vent connector. Different • Rise • Available total height “H”
appliance, vent connector, or common vent types are possible. Consult • Available total height “H” • Table 504.3(1) common vent
Section 502.3. • Table 504.3(1) connectors
FIGURE B-11 FIGURE B-13
USE OF MANIFOLD COMMON VENT CONNECTOR MULTISTORY GAS VENT DESIGN PROCEDURE
FOR EACH SEGMENT OF SYSTEM

USE INDIVIDUAL LISTED CAP
VENT FOR
TOP FLOOR
APPLIANCE IF
CONNECTOR
REQUIREMENT FOR
RISE OF TOTAL USE AVAILABLE TOTAL HEIGHT FOR TOP
HEIGHT CANNOT FLOOR APPLIANCE AND COMBINED INPUT
BE MET OF ALL APPLIANCES ON COMMON VENT
AVAILABLE TOTAL
HEIGHT FOR TOP
FLOOR APPLIANCE
THIRD INTERCONNECTION TEE*
USE VENT CONNECTOR TABLE
AVAILABLE TOTAL HEIGHT FOR THIRD
FLOOR APPLIANCE
RISE
AVAILABLE TOTAL HEIGHT FOR THIRD FLOOR
TOP FLOOR APPLIANCE APPLIANCE AND COMBINED INPUT OF THREE
APPLIANCES (IF TOP FLOOR APPLIANCE IS NOT
CONNECTED, MEASURED TOTAL HEIGHT TO
4 VENT TOP)
USE VENT CONNECTOR TABLE SECOND INTERCONNECTION TEE*
RISE USE AVAILABLE TOTAL HEIGHT FOR SECOND
FLOOR APPLIANCE AND COMBINED HEAT INPUT
OF TWO APPLIANCES
THIRD FLOOR APPLIANCE
AVAILABLE TOTAL HEIGHT FOR SECOND
3 FLOOR APPLIANCE
FIRST INTERCONNECTION TEE*
USE VENT CONNECTOR TABLE
RISE
SECOND FLOOR APPLIANCE
DESIGN VENT CONNECTOR FOR
FIRST FLOOR APPLIANCE AS AN
2 INDIVIDUAL VENT OF THIS TOTAL
HEIGHT FOR INPUT OF FIRST
FLOOR APPLIANCE
USE VENT CONNECTOR TABLE
FIRST FLOOR APPLIANCE
TEE WITH CAP OPTIONAL
1 * EACH INTERCONNECTION TEE IS SAME SIZE AS
THE SEGMENT OF COMMON VENT DIRECTLY ABOVE
Example: Offset Common Vent
Note: This is an illustration of a typical offset vent. Different appliance, vent Principles of design of multistory vents using vent connector and common
connector, or vent types are possible. Consult Sections 504.2 and 504.3. vent design tables (see Sections 504.3.11 through 504.3.17).
FIGURE B-12 FIGURE B-14
USE OF OFFSET COMMON VENT MULTISTORY VENT SYSTEMS
156 2018 INTERNATIONAL FUEL GAS CODE ®
Copyrighted © 2017 by, or licensed to, ICC (ALL RIGHTS RESERVED); licensed to UL, LLC pursuant to License Agreement with ICC. No further reproductions authorized or distribution authorized.
ANY UNAUTHROIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT; AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.