SERVICE AND TECHNICAL SUPPORT MANUAL
Gas Furnace: (F/G)9MXT
Specifications subject to change without notice.
8
440 04 4321 02
Table 2 (CONT.)
Orifice Size and Manifold Pressure (in. w.c.) for Gas Input Rate
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
Figure 4
Furnace Control Board
TEST / TWIN
HUM
PLT
PL1
W2 Y1 DHUM G COM W/W1 Y/Y2 R
24V
FUSE 3AMP
EAC2
EAC1
L1
BL1 XFMR
L2
COM
HI HT
COOL
LO H T
SPARE 1
24V MTR
TAPS
BLOWER SPEED
TERMINALS
115VAC (L2)
NEUTRAL
CONNECTIONS
LED OPERATION
& DIAGNOSTIC LIGHT
3AMP FUSE
24V THERMOS TAT
TERMINALS
SET UP SWITCHES
THERMOSTAT TYPE (TT)
AND HEAT OFFDELAY
TWINNING AND/OR
COMPONENT TEST
TERMINAL
HUMIDIFIER TERMINAL
(24 VAC 0.5 AMPS MAX)
TRANSFORMER
24 VAC CONNECTIONS
P1 LOW VOLTAGE
P2 HOT SURFACE
IGNITER/INDUCE R
MOTOR CONNECTION
115 VA C
BLOWER POWER (BL1)
CONNECTION
115 VAC LINE (L1)
INPUT
TT
OFF
DLY
ON
OFF
1 2 3
IDR
HSIR
IDM
IHI/LOR
PL2
1
HSI HI LO
1
EAC TERMINAL
115 VAC 1.0 AMP
MAX
115 VA C
TRANSFORMER
PRIMARY
SPARE 2
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ÎÎÎÎÎÎÎÎÎÎÎ
HUM
115 VAC HUM
COM/BLUE 24VAC/RED
CO
M
24V
24VAC
