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Finned copper tube gas boilers & water heaters – Boiler Manual
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Figure 5
VENT OPTION 2: VERTICAL CHIMNEY VENTING
Vertical venting — with a metal chimney system
See Figure 4, page 7 for minimum pipe diameters.
Figure 6
VENT OPTION 2: VERTICAL CHIMNEY VENTING
Vertical venting — using a lined masonry chimney
See Figure 4, page 7 for minimum pipe diameters.
OPTION 2: VERTICAL VENTING
POSITIVE PRESSURE, CATEGORY IV
FIGURE 5 OR FIGURE 6
(VENT PIPE EQUIVALENT LENGTH UP TO 100 FEET MAXIMUM)
Masonry chimneys, when used, must be lined with a
metal liner certifi ed for Category IV venting.
A thorough inspection of the masonry chimney must be
performed to ensure that the chimney is clean, properly constructed,
lined and sized. Exterior masonry chimneys should not be used
unless properly lined to prevent condensation and draft problems.
Table 4 lists the equivalent breeching and fl ue sizes required for the
boiler/water heater.
Vent connections
Locate the boiler/water heater as close to the chimney as
possible. Use the shortest, straightest vent connector possible for
the installation. If horizontal runs exceed 5 ft , 1.5 m they must be
supported at 3 ft , 0.9 m intervals with overhead hangers.
Th e vent connector should be sloped up toward the chimney at a
minimum rate of ¼ in/ft , 21 mm/m. On masonry chimneys the
connector must terminate fl ush with the inside of the chimney fl ue,
Figure 8, page 13.
Always provide a minimum clearance of 6 inches, 152 mm between
single wall vent pipe and any combustible materials.
Failure to maintain minimum clearances between vent
connectors and any combustible material can result
in a fire causing extensive property damage, severe
personal injury or death!
