10
Roof Pitch (X/12) H (Min. ft)
Flat to 6/12 1
6/12 to 7/12 1.25
Over 7/12 to 8/12 1.5
Over 8/12 to 9/12 2
Over 9/12 to 10/12 2.5
Over 10/12 to 11/12 3.25
Over 11/12 to 12/12 4
Over 12/12 to 14/12 5
Over 14/12 to 16/12 6
Over 16/12 to 18/12 7
Over 18/12 to 20/12 7.5
Over 20/12 to 21/12 8
Table F: Minimum Height from Roof to Lowest
Discharge Opening
Refer to Fig. 4 for graphical reference
For connections to gas vents or chimneys, vent instal-
lations shall be in accordance with the Venting of
Equipment section of the National Fuel Gas Code,
ANSI Z223.1, or applicable provisions of the local
building codes.
Common Vents
Manifolds that connect more than one boiler to a com-
mon chimney must be sized to handle the combined
load. Consult available guides for proper sizing of the
manifold and the chimney. At no time should the area
be less than the area of the largest outlet.
Fig. 5: Minimum Venting Measurements
WARNING: These boilers must not be connected
i
nto any portion of mechanical draft systems
operating under positive pressure. To do so may
cause the flue products to be discharged into the
living space causing serious health injury.
Fig. 6: Common Venting