8
Vertical Concentric Venting:
Figure 8.1
Vertical Concentric Vent (Back view typical)
1.
The vent must terminate with a Gary Steel Model 1092 or
Briedert Type L cap for the appropriate pipe size.
2.
The combustion air pipe must terminate with the cap
supplied by the manufacturer. This cap is specially designed
to work with the concentric vent system. Refer to the parts
list on page 6 for the appropriate part.
3.
The bottom of the air intake pipe must terminate above the
snow line, or at least 12 inches above the roof, which ever
distance is greater.
4.
The bottom of the vent cap must terminate at least 6 inches
above the top of the air intake cap.
5.
To attach the caps, slide the combustion air cap over the
vent pipe and fasten it to the combustion air pipe with at
least 3 non corrosive fasteners. Then, attach the vent cap to
the vent pipe, also using at least 3 non corrosive fasteners.
6.
Caulk the gap between the combustion air cap and the vent
pipe with silicone sealant, or other appropriate sealants
suitable for metal to metal contact and for temperatures of
350° F.
2 Pipe Venting
Two pipe venting refers to using two penetrations through an
exterior wall or roof. This method of venting is primarily used
for replacement units where two holes through the exterior of a
building exist. To vent using this method, either (2) Briedert Type
L style caps or (2) Gary Steel Model 1092 (3" part #5H72285B5,
4" part #5H72285B1) caps must be used. These caps are used
for both vertical and horizontal venting of the units.
Vertical 2 Pipe Venting
1.
Construct the vent system as shown in Figure 8.2.
2.
The bottom of the combustion air cap must be located
above the snow line or 12 inches above the roof, which ever
is greater.
3.
The vent must terminate at least 1 foot above and 6 inches
horizontally from the combustion air inlet.
4.
When the vent passes through a combustible roof, a
metal thimble 4 inches greater than the vent diameter is
necessary. If there are 6 feet or more of vertical vent pipe
in the open space between the unit heater and where the
vent pipe passes through the roof, the thimble need only
be 2 inches greater than the diameter of the vent pipe. If
a thimble is not used, all combustible material must be cut
away to proved a 6 inch clearance. Any material used to
close the opening must be noncombustible.
Figure 8.2
Vertical 2 Pipe Vent
Horizontal 2 Pipe Venting
1.
Construct the vent system as shown in Figure 8.3.
Figure 8.3
Horizontal 2 Pipe Vent
2.
When horizontal vents pass through a combustible wall (up
to 22 inches thick), the vent passage must be constructed
and insulated as shown in Figure 8.4.
Figure 8.4
Exhaust Vent Construction Through Combustible
Walls and Support Bracket
3.
The termination of horizontally vented system must extend
16 inches beyond the exterior surface of an exterior wall.
4.
The combustion air pipe must be a minimum of 6 inches
below the vent pipe, and 4 inches from the exterior wall.
5.
Support the vent and combustion air pipe as shown in
Figure 8.4.
Combustion Air
Inlet Terminal
Outlet Vent
Termination Cap
Building
Roof / Ceiling
Combustion Air
Exhaust
* SIZE ACCORNING
TO EXPECTED
SNOW DEPTH.
TO WALL OR ADJOINING BUILDING
12" MIN
12" MIN*
2' MIN
6" MIN
USE THIMBLE
THROUGH
CELLING
TEE WITH DRIP LEG
AND CLEANOUT CAP
ROOF FLASHING
TERMINAL
TERMINAL
COMBUSTION AIR
EXHAUST
SLOPE 1/4" PER FOOT
DOWNWARD FROM UNIT
TEE WITH DRIP LEG AND
CLEANOUT CAP AT LOW
POINT OF VENT SYSTEM
TERMINAL
SUPPORT BRACKET
6" MIN
2' MIN
4" MIN
12"
ADJACENT
BUILDING
METAL
SLEEVE
FIBER GLASS
INSULATION
MIN. 2"
2" MIN.
VENT TERMINATION
SUPPORT BRACKET
(where required)
(Make from 1" x 1" steel angle)
9"
9"
45
°
1"
METAL
SLEEVE
2" MIN.
VENT PIPE
DIAMETER
METAL FACE
PLATE
1"
INSTALLATION
