Modine HDS Serie Manuel D'installation Et D'entretien page 9

InsTAllATIon - venTIng
section C – Horizontal 2-pipe vent system
Installation
C1. This section applies to horizontally vented 2-pipe
vent systems (one combustion air inlet pipe and one
vent pipe) and is in addition to "Section A – General
Instructions – All Units".
C2. Horizontal vent systems terminate horizontally
(sideways).
C3. All horizontal vents must be terminated with a Gary Steel
1092 vent cap. The cap must terminate a minimum
distance from the external wall, as summarized in
Figure 9.1.
C4 . The termination of horizontally vented system must
extend 16 inches beyond the exterior surface of an
exterior wall.
C5 . The combustion air pipe must be a minimum of 6 inches
below the vent pipe, and 4 inches from the exterior wall.
C6. Construct the vent system as shown in Figure 9.1.
figure .1 - Horizontal venting with downward pitch
ADJACENT
BUILDING
2' MIN 12"
6" MIN
SPECIFIED
TERMINAL
4" MIN
SUPPORT BRACKET
C7. 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 9.2.
C8. The vent must be supported as shown in Figure 9.2.
figure .2 - exhaust vent Construction Through
Combustible Walls and support Bracket
METAL
SLEEVE
2" MIN.
VENT PIPE
DIAMETER
METAL FACE
METAL
SLEEVE
2" MIN.
1"
C9. When condensation may be a problem, the vent system
shall not terminate over public walkways or over an area
where condensate or vapor could create a nuisance
or hazard or could be detrimental to the operation of
regulators, relief openings, or other equipment.
C10. Maintain a 1/4" per foot downward slope away from the
heater and place a drip leg with clean out near the exit of
the vent as shown in Figure 9.1, or allow the condensate
to drip out the end.
SLOPE 1/4" PER FOOT
DOWNWARD FROM UNIT
EXHAUST
COMBUSTION AIR
TEE WITH DRIP LEG AND
CLEANOUT CAP AT LOW
POINT OF VENT SYSTEM
FIBER GLASS
INSULATION
MIN. 2"
PLATE
1"
9"
VENT TERMINATION
45° SUPPORT BRACKET
9" (where required)
(Make from 1" x 1" steel angle)
C11. For a vent termination located under an eave, the
distance of the overhang must not exceed 24". The
clearance to combustibles above the exterior vent
must be maintained at a minimum of 12". Consult the
National Fuel Gas Code for additional requirements for
eaves that have ventilation openings.
C12. Once venting is complete, proceed section titled
"Installation – Gas Connections".
6-584.2