22
18-CD19D8-18
Installer’s Guide
6" Min.
40 Inch
Upflow or
Downflow
Furnace
Slope 1/4" per ft.
Slope 1/4" per ft.
All horizontal pipes must be
supported at maximum of 3
foot intervals
DOWNWARD VENTING
Furnace may be in vertical or horizontal configuration.
/
NOTES:
A)
Condensate trap for vent pipe must be a minimum of 6 inches in height.
B)
Condensate trap for vent and inlet pipe must be connected into a condensate drain pump; an open or
vented drain; or it can be connected to the outlet hose of the furnace's condensate trap. Outdoor drain-
ing of the furnace and coil condensate is permissible if allowed by local codes. Caution should be taken
to prevent drains from freezing or causing slippery conditions that could lead to personal injury. Exces-
sive draining of condensate may cause saturated ground conditions that may result in damage to plants.
C)
The condensate trap should be primed at initial start up prior to heating season operation.
DOWNWARD VENT LENGTH IS
LIMITED TO A MAXIMUM OF 15
EQUIVALENT FEET.
TABLE 12 Direct Vent Terminal Clearances
Canadian Installations
US Installations
A=
Clearance above grade, veranda, porch,
deck, or balcony
12 inches (30 cm)
12 inches (30 cm)
B=
Clearance to window or door that may be
opened
6 inches (15 cm) for appliances =/< 10,000 Btuh (3 kw),
12 inches (30 cm) for appliances > 10,000 Btuh (3 kw)
and =/< 100,000 Btuh (30 kw),
36 inches (91 cm) for appliances > 100,000 Btuh (30 kw)
6 inches (15 cm) for appliances =/< 10,000 Btuh (3 kw),
9 inches (23 cm) for appliances > 10,000 Btuh (3 kw)
and =/< 50,000 Btuh (15 kw),
12 inches (30 cm) for appliances > 50,000 Btuh (15 kw)
C=
Clearance to permanently closed window
*
*
D=
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet (61 cm)
from the center line of the terminal
*
*
E=
Clearance to unventilated soffit
*
*
F=
Clearance to outside corner
*
*
G=
Clearance to inside corner
*
*
H=
Clearance to each side of center line
extended above meter/regulator assembly
3 feet (91 cm) with a height 15 feet (4.5 m) above the
meter/regulator assembly
*
I=
Clearance to service regulator vent outlet
3 feet (91 cm)
*
J=
Clearance to nonmechanical air supply
inlet to building or the combustion air
inlet to any other appliance
6 inches (15 cm) for appliances =/< 10,000 Btuh (3 kw),
12 inches (30 cm) for appliances > 10,000 Btuh (3 kw)
and =/< 100,000 Btuh (30 kw),
36 inches (91 cm) for appliances > 100,000 Btuh (30 kw)
6 inches (15 cm) for appliances =/< 10,000 Btuh (3 kw),
9 inches (23 cm) for appliances > 10,000 Btuh (3 kw)
and =/< 50,000 Btuh (15 kw),
12 inches (30 cm) for appliances > 50,000 Btuh (15 kw)
K=
Clearance to a mechanical air supply inlet
6 feet (1.83m)
3 feet (91 cm) above if within 10 feet (3m) horizontally
L=
Clearance above a paved sidewalk or
paved driveway located on public property
7 feet (2.13 m) †
*
M=
Clearance under veranda, porch, deck,
or balcony
12 inches (30 cm) ‡
*
Notes:
1. In accordance with the current CSA B149.1 Natural Gas and Propane Installation Code.
2. In accordance with the current ANSI Z223.1/NFPA 54 National Fuel Gas Code.
†. A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwelling and serves both dwellings.
‡. Pemitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
* Clearance in accordance with local installation codes and the requirements of the gas supplier and the manufacturer's Installation Instructions.
