Rinnai Tankless Water Heater Installation and Operation Manual
27
4.5.4 Direct Vent (Indoor): Termination Clearances
U.S. Installations
1
(ANSI Z223.1/NFPA 54)
Ref
Description
Direct Vent (Indoor Unit)
A
Clearance above grade, veranda, porch, deck, or balcony
12 in. (30 cm)
B
Clearance to window or door that may be opened
12 in. (30 cm)
C
Clearance to permanently closed window
*
D
Vertical clearance to ventilated soffit, located above the 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
12 in.
H
Clearance to each side of center line extended above meter/regulator
assembly
*.
I
Clearance to service regulator vent outlet
*
J
Clearance to non-mechanical air supply inlet to building or the
combustion air inlet to any other appliance
12 in. (30 cm)
K
Clearance to a mechanical air supply inlet
3 ft (91 cm) above if within 10 ft (3 m) horizontally
L
Clearance above paved sidewalk or paved driveway located on public
property
Vents for Category II and IV appliances cannot be located
above public walkways or other areas where condensate or
vapor can cause a nuisance or hazard.
M
Clearance under veranda, porch, deck, or balcony
*
Clearance to opposite wall is 24 in. (60 cm).
[1] A vent shall not terminate directly above a sidewalk or paved driveway that is
located between two single family dwellings and serves both dwellings.
[2] Permitted only if veranda, porch, deck, or balcony is fully open on a minimum
of two sides beneath the floor.
*Clearances are in accordance with local installation codes
and the requirements of the gas supplier.
AIR SUPPLY INLET
VENT TERMINAL
AREA WHERE TERMINAL
IS NOT PERMITTTED
X
V
SNOW
TERMIN
A
TION
Clearance in
Ref.
A also
applies to
anticipated
snow line
Regulator vent outlet
AIR SUPPLY INLET
VENT TERMINAL
AREA WHERE TERMINAL
IS NOT PERMITTTED
X
V
SNOW
TERMIN
A
TION
Clearance in
Ref.
A also
applies to
anticipated
snow line
Figure 20: Direct Vent Termination Clearances
Table 10
Notes:
1
In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code.
I
If locally adopted installation codes specify clearances different than those illustrated, then the most stringent clearance shall prevail.