INSTALLATION INSTRUCTIONS
Gas Furnace: (F/G)9MVT, (F/G)9MXT, (F/G)9MXE
12
440 01 4001 05
Specifications subject to change without notice.
Table 4
Minimum Space Volumes for 100% Combustion, Ventilation and Dilution Air from Outdoors
OTHER THAN FAN‐ASSISTED TOTAL
(1,000'S BTUH GAS INPUT RATE)
FAN‐ASSISTED TOTAL
(1,000'S BTUH GAS INPUT RATE)
ACH
30
40
50
40
60
80
100
120
140
Space Volume Ft
3
(M
3
)
0.60
1,050
(29.7)
1,400
(39.6)
1,750
(49.5)
1,400
(39.6)
1,500
(42.5)
2,000
(56.6)
2,500
(70.8)
3,000
(84.9)
3,500
(99.1)
0.50
1,260
(35.6)
1,680
(47.5)
2,100
(59.4)
1,680
(47.5)
1,800
(51.0)
2,400
(67.9)
3,000
(84.9)
3,600
(101.9)
4,200
(118.9)
0.40
1,575
(44.5)
2,100
(59.4)
2,625
(74.3)
2,100
(59.4)
2,250
(63.7)
3,000
(84.9)
3,750
(106.1)
4,500
(127.3)
5,250
(148.6)
0.30
2,100
(59.4)
2,800
(79.2)
3,500
(99.1)
2,800
(79.2)
3,000
(84.9)
4,000
(113.2)
5,000
(141.5)
6,000
(169.8)
7,000
(198.1)
0.20
3,150
(89.1)
4,200
(118.9)
5,250
(148.6)
4,200
(118.9)
4,500
(127.3)
6,000
(169.8)
7,500
(212.2)
9,000
(254.6)
10,500
(297.1)
0.10
6,300
(178.0)
8,400
(237.8)
10,500
(297.3)
8,400
(237.8)
9,000
(254.6)
12,000
(339.5)
15,000
(424.4)
18,000
(509.2)
21,000
(594.1)
0.00
NP
NP
NP
NP
NP
NP
NP
NP
NP
NP = Not Permitted
CONDENSATE TRAP
Condensate Trap
−
Upflow Orientation
When the furnace is installed in the upflow position, it is not
necessary to relocate the condensate trap or associated
tubing. Refer to
Figure 8
for upflow condensate trap
information. Refer to Condensate Drain section for information
how to install the condensate drain.
Condensate Trap
−
Downflow
Orientation
When the furnace is installed in the downflow position, the
condensate trap will be initially located at the upper left corner
of the collector box, as received from the factory. See the top
image in
Figure 9
. When the furnace is installed in the
downflow orientation, the condensate trap must be relocated
for proper condensate drainage. See the bottom image in
Figure 9
.
To Relocate the Condensate Trap:
Orient the furnace in the downflow position.
Figure 9
shows the condensate trap and tubing before and
after relocation. Refer to
Figure 9
to begin the trap conversion.
Refer to Condensate Drain section for information how to install
the condensate drain.
Figure 8
Upflow Trap Configuration
Condensate Trap
Relief Port
Collector Box
Plugs
Pressure Switch
Port
Condensate Trap
Outlet
Condensate Trap
Relief Port
Collector Box
Plug
Vent Elbow
Vent Elbow Clamp
Vent Pipe Clamp
UPFLOW TRAP CONFIGURATION
1 & 2 Stage Units
A11307
Representative drawing only, some models may vary in appearance.
