INSTALLATION INSTRUCTIONS
Gas Furnace: (F/G)MAC
44
440 01 4201 01
Specifications subject to change without notice.
Figure 59
Direct Vent Termination Clearance
V
V
Item
Clearance Description
Canadian Installation (1)
U.S. Installation (2)
A
Clearance above grade, veranda, porch, deck, balcony, or
anticipated snow level
12 in. (305 mm). 18 in. (457mm) above roof surface
12 in. (305 mm)
B
Clearance to a window or door that may be opened
12 in. (305 mm) for appliances
u
10,000 Btuh (3 kW) and
v
100,000 Btuh (30 kW), 36 in. (914 mm) for appliances
u
100,000 Btuh (30 kW)
9 in. (229 mm) for appliances
u
10,000 Btuh (3 kW) and
v
50,000 Btuh (14.7 kW), 12
″
(30 cm) for appliances
u
50,000
Btuh (14.7 kW)
C
Clearance to a permanently closed window
For clearances not specified in ANSI Z223.1/NFPA 54 or
CAN/CSA B149.1, clearances shall be in accordance with
local installation codes and the requirements of the gas suppli
er and the manufacture's installation instructions.
For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/
CSA B149.1, clearances shall be in accordance with local instal
lation codes and the requirements of the gas supplier and the
manufacture's installation instructions.
D
Vertical clearance to a ventilated soffit located above the
terminal within a horizontal distance of 2
′
(61cm) from the
centerline of the terminal
E
Clearance to an unventilated soffit
F
Clearance to an outside corner
G
Clearance to an inside corner
H
Clearance to each side of the centerline extended above
electrical meter or gas service regulator assembly
3 ft. (.9 m) within a height15 feet (4.5 m) above the meter/reg
ulator assembly
3 ft. (.9 m) within 15 feet (4.5 m) above the meter/regulator
assembly
I
Clearance to service regulator vent outlet
3 ft. (.9 m)
3 ft. (.9 m) For clearances not specified in ANSI Z223.1/NFPA
54 or CAN/CSA B149.1, clearances shall be in accordance with
local installation codes and the requirements of the gas supplier
and the manufacture's installation instructions.
J
Clearance to non-mechanical air supply inlet to building or the
combustion air inlet to any other appliance
12 in. (305 mm) for appliances
u
10,000 Btuh (3 kW) and
v
100,000 Btuh (30 kW), 36
″
(91 cm) for appliances
u
100,000
Btuh (30 kW)
9 in. (23 cm) for appliances
u
10,000 Btuh (3 kW) and
v
50,000 Btuh (15 kW), 12
″
(30 cm) for appliances
u
50,000
Btuh (14.7 kW)
K
Clearance to a mechanical air supply inlet
6 ft. (1.8 m)
3 ft. (.9 m) above if within 10
′
(3m) horizontally
L
Clearance under a veranda, porch, deck, or balcony
12 in. (305 mm) Permitted only if veranda, porch, deck, or
balcony is fully open on a minimum of two sides beneath the
floor.
For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/
CSA B149.1, clearances shall be in accordance with local instal
lation codes and the requirements of the gas supplier and the
manufacture's installation instructions.
M
Clearance to each side of the centerline extended above or
below vent terminal of the furnace to a dryer or water heater
vent, or other appliance's direct vent intake or exhaust.
12 in. (305 mm)
12 in. (305 mm)
N
Clearance to the vent terminal of a dryer vent, water heater
vent, or other appliances direct vent intake or exhaust.
3 ft. (.9 m)
3 ft. (.9 m)
O
Clearance from a plumbing vent stack
3 ft. (.9 m)
3 ft. (.9 m)
P
Clearance above a paved sidewalk or paved driveway located
on public property.
7 ft. (2.1 m) A vent shall not terminate directly above a side
walk or paved driveway that is located between two single
family dwellings and serves both dwellings.
For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/
CSA B149.1, clearances shall be in accordance with local instal
lation codes and the requirements of the gas supplier and the
manufacture's installation instructions.
u
greater than,
w
greater than or equal to,
t
less than,
v
less than or equal to
(1) In accordance with the current CAN/CSA B149.1, Natural Gas and Propane Installation Code
(2) In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code
Notes:
1
The vent for this appliance shall not terminate
a. Over public walkways; or
b. Near soffit vents or crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or property damage; or
c. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.
2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion products of adjacent vents.
Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of the heat exchangers.
3. Avoid venting under a deck or large overhang. Recirculation could occur and cause performance or system problems.
