10
• The connector must be firmly attached and
sealed to prevent it from falling out.
• To aid in removing the connector, a thimble or
slip joint may be used.
• The connector must not extend beyond the
inner edge of the chimney as it may restrict
the space between it and the opposite wall of
the chimney
Chimney Termination Vent System
Seal
Do Not Extend
Vent Beyond Edge
Of Chimney
Maintain
Clearance*
Support Strap
3 FT.
Minimum
2 FT. Minimum Above Any Object
Within 10 FT. Horizontally
Slope Up
1/4 Inch
Per Foot
Minimum
Vent
Connector
Figure 8.
Do not reduce the vent to less than the draft
hood outlet diameter. Do not terminate the vent
connector in a chimney that has not been certified
for this purpose. Some local codes may prohibit
the termination of vent connectors in a masonry
chimney.
Vertical Exhaust Gas Vent: Vertical exhaust
gas vents must be installed with U.L. listed type
B vent pipe according to the vent manufacturer’s
instructions and the terms of its listing.
It must be connected to the water heater’s draft
hood by a listed vent connector or by directly
originating at the draft hood opening.
Vertical gas vents must terminate with a listed cap
or other roof assembly and be installed according to
their manufacturer’s instructions.
Gas vents must be supported to prevent damage,
joint separation, and maintain clearances to
combustible materials.
IMPORTANT: This gas vent must be terminated in a
vertical position to facilitate the removal of the burnt
gases.
An unused chimney fl ue or masonry enclosure
may be used as a passageway for the installation
of a gas vent. NOTE: The chimney fl ue or masonry
enclosure size may be too large to allow proper
venting.
Common (combined) venting is allowable with
vertical type B vent systems and lined masonry
chimneys as long as proper draft for the water
heater is established under all conditions of
operation. CAUTION: DO NOT common vent this
water heater with any power vented appliance.
The following fi gures are examples of vent pipe
system installations and may or may not be typical
for your specifi c application. Consult the “National
Fuel Gas Code”, NFPA 54, ANSI Z223.1-current
edition and the guidelines set forth by prevailing
local codes.
Maintain
Clearance*
Support Strap
3 FT.
Minimum
Vent
Connector
Slope Up
1/4 Inch
Per Foot
Minimum
**Maintain
Specified
Clearance
Venting Gas Vent System With Type B Double Wall Vent Pipe.
2 FT. Minimum Above
Any Object Within
10 FT. Horizontally
Type B Double
Wall Vent Pipe
Figure 9.
Consult the table found in the “National Fuel Gas
Code”, NFPA 54, ANSI Z223.1-current edition to
determine the minimum height from roof to lowest
discharge opening.
Seal
Maintain
Clearance*
Support Strap
Specified Minimum Clearance
Vent
Connector
Slope Up
1/4 Inch
Per Foot
Minimum
Vent Connector
**Maintain
Specified
Clearance
Venting Through Chimney With Type B Double Wall Vent Pipe.
Unused Chimney
Flue Or Masonry
Enclosure
Maintain Manufacturer’s
Listed Vent Cap
Figure 10.
*
Maintain vent pipe clearance requirements to local,
state and/or the “National Fuel Gas Code”, ANSI
Z223.1(NFPA 54)-current edition.
**
NFPA 211, Standard for Chimneys, Fireplaces,
Vents, and Solid Fuel-Burning Appliances states
that these chimneys are intended to be installed
in accordance with the installation instructions
provided with each chimney support assembly.
Minimum air space clearance to combustible
materials should be maintained as marked on the
chimney sections.
COMBUSTION AIR AND VENT SYSTEM REQUIREMENTS