Navien NHB H Series Installation And Operation Manual page 58

Terminal Clearances for Direct Vent Installations
Ref Description
A Clearance above grade, veranda, porch, deck, or balcony 12 in (30 cm)
B Clearance to window or door that may be opened
C Clearance to permanently closed window
Vertical clearance to ventilated soffit located above the
D terminal within a horizontal distance of 2 ft (61 cm) from
the center line of the terminal
E Clearance to unventilated soffit
F Clearance to outside corner
G Clearance to inside corner
Clearance to each side of center line extended above
H
meter/regulator assembly
I Clearance to service regulator vent outlet
Clearance to nonmechanical air supply inlet to building
J
or the combustion air inlet to any other appliance
K Clearance to a mechanical air supply inlet
Clearance above paved sidewalk or paved driveway
L
located on public property
M Clearance under veranda, porch deck, or balcony
* Suggested clearances by the manufacturer. If the clearances required by local codes are different from those from the table above,
the greater clearance should apply.
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
3 If locally adopted installation codes specify clearances different than those illustrated, then the most stringent clearance shall prevail.
4 Soffit with 12" depth requires a minimum of 12" vertical clearance from the termination (36" soffit requires a minimum of 36"
vertical clearance)
5 In the areas where corrosion and discoloration of building materials can occur, a minimum clearance of 12" shall apply.
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and
serves both dwellings.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
Direct exhaust vapors and condensate away from building materials to avoid degradation. The minimum distance from adjacent
public walkways, adjacent buildings, openable windows, and building openings shall not be less than those values specified in the
National Fuel Gas Code, ANSI Z223.1/NFPA 54, and/or the Natural Gas and Propane Installation Code, CSA B149.1.
58 Venting for Combustion Air
Canadian Direct Vent
Installations
1
36 in (91 cm)
0 in (0 cm)
5
Equal or greater than
soffit depth
4, 5
Equal or greater than
soffit depth
4, 5
2 ft (61 cm)*
12 in (30 cm)*
3 ft (91 cm) within a
height 15 ft above the
meter/regulator assembly
3 ft (91 cm)
36 in (91 cm)
6 ft (1.83 m)
7 ft (2.13 m)
†
12 in (30 cm)
‡
US Direct Vent
Installations
2
12 in (30 cm)
12 in (30 cm)
0 in (0 cm)
5
Equal or greater than
soffit depth
4, 5
Equal or greater than
soffit depth
4, 5
2 ft (61 cm)*
12 in (30 cm)*
3 ft (91 cm) within a
height of 15 ft (4.6 m)*
3 ft (91 cm)*
12 in (30 cm)
3 ft (91 cm) above
if within 10 ft (3 m)
horizontally
7 ft (2.13 m)
†
12 in (30 cm) - open
on 3 sides*