8
441 01 1411 04
Specifications are subject to change without notice.
Table 3 – Minimum Space volumes for 100% combustion, Ventilation, and Dilution from Indoors
ACH
OTHER THAN FAN
−
ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE
FAN
−
ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE)
30
40
50
44
66
88
110
132
Space Volume (ft.
3
)
0.60
1,050
1,400
1,750
1,100
1,650
2,200
2,750
3,300
0.50
1,260
1,680
2,100
1,320
1,980
2,640
3,300
3,960
0.40
1,575
2,100
2,625
1,650
2,475
3,300
4,125
4,950
0.30
2,100
2,800
3,500
2,200
3,300
4,400
5,500
6,600
0.20
3,150
4,200
5,250
3,300
4,950
6,600
8,250
9,900
0.10
6,300
8,400
10,500
6,600
9,900
13,200
16,500
19,800
0.00
NP
NP
NP
NP
NP
NP
NP
NP
ACH = Air Changes/Hour
NP = Not Permitted
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
Do not install the furnace on its back or hang furnace
with control compartment facing downward. Safety
control operation will be adversely affected. Never
connect return
−
air ducts to the back of the furnace.
(See Figure 6)
!
WARNING
Figure 6
−
Prohibit Installation on Back
A02054
FURNACE CORROSION HAZARD
Failure to follow this caution may result in furnace
damage.
Air for combustion must not be contaminated by
halogen compounds, which include fluoride, chloride,
bromide, and iodide. These elements can corrode
heat exchangers and shorten furnace life. Air
contaminants are found in aerosol sprays,
detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products.
CAUTION
!
LOCATION RELATIVE TO COOLING EQUIPMENT
The cooling coil must be installed parallel with, or on the
downstream side of the unit to avoid condensation in the heat
exchangers. When installed parallel with the furnace,
dampers or other flow control must prevent chilled air from
entering the furnace. If the dampers are manually operated,
they must be equipped with means to prevent operation of
either unit unless the damper is in the full
−
heat or full
−
cool
position.
AIR FOR COMBUSTION AND
VENTILATION
Provisions for adequate combustion, ventilation, and dilution
air must be provided in accordance with:
S
U.S. installations: Section 9.3 of the NFGC
NFPA54/ANSI Z223.1
−
2012, Air for Combustion and
Ventilation, and applicable provisions of the local
building codes.
!
WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
The operation of exhaust fans, kitchen ventilation
fans, clothes dryers, attic exhaust fans or fireplaces
could create a NEGATIVE PRESSURE CONDITION
at the furnace. Make
−
up air MUST be provided for the
ventilation devices, in addition to that required by the
furnace. Refer to Carbon Monoxide Poisoning Hazard
warning in venting section of these instructions to
determine if an adequate amount of make
−
up air is
available.
The requirements for combustion and ventilation air depend
upon whether or not the furnace is located in a space having
a volume of at least 50 cubic feet per 1,000 Btuh input rating
for all gas appliances installed in the space.
S
Spaces having less than 50 cubic feet per 1,000
Btuh require the
OUTDOOR COMBUSTION AIR
METHOD.
S
Spaces having at least 50 cubic feet per 1,000 Btuh
may use the
INDOOR COMBUSTION AIR,
STANDARD or KNOWN AIR INFILTRATION
METHOD.
Outdoor Combustion Air Method
1. Provide the space with sufficient air for proper combus-
tion, ventilation, and dilution of flue gases using per-
manent horizontal or vertical duct(s) or opening(s) dir-
ectly communicating with the outdoors or spaces that
freely communicate with the outdoors.
2. Figure 7 illustrates how to provide TWO OUTDOOR
OPENINGS, one inlet and one outlet combustion and
ventilation air opening, to the outdoors.
a. One opening
MUST
commence within 12
−
in. (300
mm) of the ceiling and the second opening
MUST
commence within 12
−
in. (300 mm) of the floor.
b. Size openings and ducts per Figure 7 and Table 2.
