Combustion And Ventilation Air - Desa LDL3924NR Owner's Operation And Installation Manual

AIR FOR COMbUSTION
AND VENTILATION
Continued
. . ____________ . Btu/Hr. (maximum. the.
space.can.support).
. . ____________ .Btu/Hr.(actual.amount.of.
Btu/Hr.used)
. Example:.
51,200 Btu/Hr (maximum the space can .
support).
73,000 Btu/Hr (actual amount of Btu/Hr
used)
The space in the above example is a confined
space.because.the.actual.Btu/Hr.used.is.more.
than.the.maximum.Btu/Hr.the.space.can.sup-
port.. You. must. provide. additional. fresh. air..
Your.options.are.as.follo.ws:
A. Rework worksheet, adding the space
of.an.adjoining.room..If.the.extra.space.
provides an unconfined space, remove
door.to.adjoining.room.or.add.ventilation.
grills.between.rooms..See.Ventilation Air
From Inside Building.
B.. Vent.room.directly. to. the. outdoors.. See.
Ventilation Air From Outdoors.
C. Install a lower Btu/Hr heater, if lower
Btu/Hr size makes room unconfined.
WARNING: If the area in
which the heater may be oper-
ated is smaller than that defined
as an unconfined space or if the
building is of unusually tight
construction, provide adequate

combustion and ventilation air

by one of the methods described
in the National Fuel Gas Code,
ANSI Z223.1/NFPA 54, Air for
Combustion and Ventilation or
applicable local codes.
VENTILATION AIR
Ventilation Air From Inside Building
This.fresh.air.would.come.from.an.adjoining.
unconfined space. When ventilating to an
adjoining unconfined space, you must provide
two.permanent.openings:.one.within.1".of.the.
111515-01J
ceiling and one within 12" of the floor on the
wall.connecting.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, ANSI
Z223.1/NFPA 54, Air for Combustion and
Ventilation for required size of ventilation
grills.or.ducts.
Ventilation
Grills Into
Adjoining
Room,
Option 1
Figure 2 - Ventilation Air from Inside
Ventilation Air From Outdoors
Provide. extra. fresh. air. by. using. ventilation.
grills.or.ducts..You.must.provide.two.perma-
nent.openings:.one.within.1".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..Follow.the.National Fuel
Gas Code, ANSI Z223.1/NFPA 54, Air for
Combustion and Ventilation for required size
of.ventilation.grills.or.ducts..
IMPORTANT: Do. not. provide. openings. for.
inlet.or.outlet.air.into.attic.if.attic.has.a.thermo-
stat-controlled.power.vent..Heated.air.entering.
the.attic.will.activate.the.power.vent.
Outlet
A ir
Inlet
Air
Figure 3 - Ventilation Air from Outdoors
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Ventilation Grills
Into Adjoining Room,
Or
Option 2
Remove
Door into
Adjoining
Room,
Option
3
12"
Building
Ventilated
Outlet
Attic
Air
Ventilated
Inlet Air
Crawl Space
12"
To Attic
To
Crawl
Space
7