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Page 21
Figure 30
VENT TERMINAL
AIR SUPPLY INLET
AREA WHERE TERMINAL IS NOT PERMITTED
VENT CLEARANCES
A = *Clearance above grade, veranda, porch, deck or balcony
[*12 inches (30cm) minimum]
B = clearance to window or door that may be opened [*12 inches
(30cm) minimum for appliances < 100,000 Btuh (30kW)
C = clearance to permanently closed window [minimum 12
inches (30cm) recommended to prevent condensation on
window]
D = vertical clearance to ventilated soffit located above the
terminal within a horizontal distance of 24 inches (60 cm)
from the center of the terminal [18 Inches (46 cm) minimum
E = clearance to unventilated soffit [12 inches 30cm) minimum]
F = clearance to outside corner [See Page 24]
G = clearance to inside corner [See Page 24]
H = *not to be installed above a meter/regulator assembly
within 3 feet (90cm) horizontally from the center-line of the
regulator
I = clearance to service regulator vent outlet [*6 feet (1.8m)
minimum]
J = clearance to non-mechanical air supply inlet to building or
the combustion air inlet to any other appliance [*12 inches
(30cm) minimum for appliances ≤ 100,000 Btuh (30 kW)
36 inches (90cm) minimum for appliances > 100,000 Btuh
(30kW)]
K = clearance to a mechanical air supply inlet [* 6 feet (1.8m)
minimum]
L = †clearance above paved sidewalk or a paved driveway
located on public property [*7 feet (2.1m) minimum]
M = clearance under veranda, porch, deck, or balcony [*12
inches (30cm) minimum ¥]
† a vent shall not terminate directly above a sidewalk or
paved driveway which is located between two single family
dwellings and serves both dwellings*
¥ only permitted if veranda, porch, deck, or balcony, is fully
open on a minimum of 2 sides beneath the floor*
* as specified in CGA B149 Installations Codes or ANSI
Z223.1. Note: Local Codes or Regulations may require
different clearances.
Distances are to non-combustible surfaces unless indicated.
