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77
Table 19 -- Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Continued)
S
A
G
L
A
R
U
T
A
N
F
O
Y
T
I
V
A
R
G
C
I
F
I
C
E
P
S
S
A
G
.
G
V
A
HEAT VALUE
0.58
0.60
0.62
0.64
AT ALTITUDE
Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press
(Btu/cu ft)
No.
High/Low
No.
High/Low
No.
High/Low
No.
High/Low
TWO-STAGE FURNACE
(TABULATED DATA BASED ON 20,000 BTUH HIGH-HEAT / 13,000 BTUH LOW-HEAT PER BURNER,
DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
ALTITUDE
RANGE
ft (m)
650
42
3.4 / 1.4
42
3.5 / 1.5
42
3.6 / 1.5
42
3.7 / 1.6
7001
675
43
3.8 / 1.6
42
3.2 / 1.4
42
3.3 / 1.4
42
3.4 / 1.5
(2134)
700
43
3.5 / 1.5
43
3.7 / 1.5
43
3.8 / 1.6
42
3.2 / 1.4
725
44
3.8 / 1.6
43
3.4 / 1.4
43
3.5 / 1.5
43
3.6 / 1.5
750
44
3.5 / 1.5
44
3.7 / 1.5
44
3.8 / 1.6
43
3.4 / 1.4
8000
775
44
3.3 / 1.4
44
3.4 / 1.4
44
3.5 / 1.5
44
3.7 / 1.5
(2438)
800
45
3.8 / 1.6
44
3.2 / 1.4
44
3.3 / 1.4
44
3.4 / 1.4
825
46
3.7 / 1.6
46
3.8 / 1.6
45
3.8 / 1.6
44
3.2 / 1.4
625
42
3.4 / 1.4
42
3.5 / 1.5
42
3.6 / 1.5
42
3.7 / 1.6
8001
650
43
3.8 / 1.6
42
3.2 / 1.4
42
3.3 / 1.4
42
3.4 / 1.4
(2439)
675
43
3.5 / 1.5
43
3.6 / 1.5
43
3.7 / 1.6
42
3.2 / 1.3
700
44
3.7 / 1.6
43
3.4 / 1.4
43
3.5 / 1.5
43
3.6 / 1.5
725
44
3.5 / 1.5
44
3.6 / 1.5
44
3.7 / 1.6
44
3.8 / 1.6
9000
750
44
3.3 / 1.4
44
3.4 / 1.4
44
3.5 / 1.5
44
3.6 / 1.5
(2743)
775
45
3.7 / 1.6
44
3.2 / 1.3
44
3.3 / 1.4
44
3.4 / 1.4
9001
600
42
3.3 / 1.4
42
3.4 / 1.5
42
3.6 / 1.5
42
3.7 / 1.6
(2744)
625
43
3.7 / 1.6
42
3.2 / 1.3
42
3.3 / 1.4
42
3.4 / 1.4
650
43
3.5 / 1.5
43
3.6 / 1.5
43
3.7 / 1.6
43
3.8 / 1.6
675
44
3.7 / 1.6
44
3.8 / 1.6
43
3.4 / 1.4
43
3.5 / 1.5
10000
700
44
3.4 / 1.4
44
3.5 / 1.5
44
3.7 / 1.5
44
3.8 / 1.6
(3048)
725
44
3.2 / 1.3
44
3.3 / 1.4
44
3.4 / 1.4
44
3.5 / 1.5
* Orifice numbers shown in
BOLD
are factory-installed.
to
to
to
U.
S
.A.
On
ly
U.
S
.A.
On
ly
U.
S
.A.
On
ly
A11252B
SERVICE AND MAINTENANCE
PROCEDURES
Untrained personnel can perform basic maintenance functions such
as cleaning and replacing air filters. All other operations must be
performed by trained service personnel. A qualified service person
should inspect the furnace once a year.
FIRE, INJURY OR DEATH HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
The ability to properly perform maintenance on this
equipment requires certain knowledge, mechanical skills,
tools, and equipment. If you do not possess these, do not
attempt to perform any service and maintenance on this
equipment other than those procedures recommended in the
Owner’s Manual.
!
WARNING
ENVIRONMENTAL HAZARD
Failure to follow this caution may result in environmental
pollution.
Remove and recycle all components or materials (i.e. oil,
refrigerant, control board, etc.) before unit final disposal.
CAUTION
!
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death, or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag.
There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
Always reinstall access doors after completing service and
maintenance.
!
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this caution may result in improper
furnace operation or failure of furnace.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous
operation.
CAUTION
!
General
These instructions are written as if the furnace is installed in an
upflow application. An upflow furnace application is where the
blower is located below the combustion and controls section of the
furnace, and conditioned air is discharged upward. Since this
furnace can be installed in any of the 4 positions shown in Fig. 2,