6
104385
UNVENTED NATURAL GAS LOG HEATER
CGS2718N, CGS3124N, CLD3018N,
CLD3924NT, and CCL3930NT(A)
AIR FOR
COMBUSTION AND
VENTILATION
Continued
WARNING: Rework work-
sheet, adding the space of the
adjoining unconfined space. The
combined spaces must have
enough fresh air to supply all
appliances in both spaces.
Figure 3 - Ventilation Air from Outdoors
Ventilation Air From Outdoors
Provide extra fresh air by using ventilation
grills or ducts. You must provide two per-
manent openings: one within 12" of the
ceiling and one within 12" of the floor.
Connect these items directly to the outdoors
or spaces open to the outdoors. These spaces
include attics and crawl spaces.
IMPORTANT:
Do not provide openings for
inlet or outlet air into attic if attic has a
thermostat-controlled power vent. Heated air
entering the attic will activate the power vent.
Figure 2 - Ventilation Air from Inside Building
Outlet
Air
Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air
Ventilated
Crawl Space
To
Crawl
Space
To Attic
Or
Remove
Door into
Adjoining
Room,
Option
3
Ventilation Grills
Into Adjoining Room,
Option 2
Ventilation
Grills
Into Adjoining
Room,
Option 1
12"
12"
VENTILATION AIR
Ventilation Air From Inside
Building
This fresh air would come from an adjoin-
ing unconfined space. When ventilating
to an adjoining unconfined space, you
must provide two permanent openings:
one within 12" of the ceiling and one
within 12" of the floor on the wall con-
necting the two spaces (see options 1 and
2, Figure 2). You can also remove door
into adjoining room (see option 3, Figure
2). Follow the National Fuel Gas Code
NFPA 54/ANS Z223.1, Section 5.3, Air for
Combustion and Ventilation for required
size of ventilation grills or ducts.
