SYSTEM OPERATION
15
T
HE
RUBBER
ELBOW
IS
NOT
DESIGNED
TO
SUPPORT
A
LOAD
. W
HEN
THE
RUBBER
ELBOW
IS
MOUNTED
EXTERNALLY
TO
THE
FURNACE
CABINET
,
EXTREME
CARE
MUST
BE
TAKEN
TO
ADEQUATELY
SUPPORT
FIELD
-
SUPPLIED
VENT
/
FLUE
PIPING
,
AS
DAMAGE
CAN
RESULT
IN
LEAKS
CAUSING
BODILY
INJURY
OR
DEATH
DUE
TO
EXPOSURE
TO
FLUE
GASES
,
INCLUDING
CARBON
MONOXIDE
WARNING
COMBUSTION AIR INTAKE OPTIONS:
The RF000142
coupling can be secured directly to the furnace intake coupling
if condensation is a concern. If the RF000142 is used on the
combustion air inlet, it must be installed with the arrow pointing
up. It should be noted, the combustion air will actually be
moving in a direction opposite of the arrow on the RF000142
coupling. It must have a field supplied, trapped drain tube
free-draining to proper condensate disposal location. A loop
in the drain tube can serve as a trap. The unused RF000142
drain fitting should be capped. A tee installed in the intake
pipe is also an acceptable method of catching condensation.
It must have a field supplied, trapped drain tube or pipe, free-
draining to proper condensate disposal location. A loop in the
drain tube can serve as a trap. (See Figure 9B)
Non-Direct Vent Installations
A minimum of one 90° elbow should be installed on the combustion
air intake “coupling” to guard against inadvertent blockage.
Alternate Vent/Flue Location
The alternate vent/flue location is the large hole directly
in line
with the induced draft blower outlet. To use the alternate vent/
flue location refer to the following steps and the “Alternate
Vent/Flue Location” figure. This option is not available with
counter-flow models.
NOTE: In the horizontal left installation position, a means of
condensate collection must be provided to keep vent pipe
condensate from entering the draft inducer housing. If the vent
drain elbow is eliminated from the installation, an RF000142
kit must be used.
1. Remove the four screws from the vent pipe flange on top
the furnace.
2. Remove the internal elbow and vent pipe.
3. Cut 2 1/2” from the flange .
4. Remove plastic plug in line with the inducer outlet
5. Install cut end of the flanged section and connect to
inducer with rubber coupling supplied with furnace.
6. Install screws removed in step 1 securing flange to
cabinet.
B
E
SURE
NOT
TO
DAMAGE
INTERNAL
WIRING
OR
OTHER
COMPONENTS
WHEN
REINSTALLING
COUPLING
AND
SCREWS
.
CAUTION
Alternate Combustion Air Provision
(Upflow / Horizontal models only)
When using the alternate venting location, either in
a horizontal left side down installation or a vertical
installation using down – venting, an alternate com
-
bustion air opening can be used. A locating dimple is
located on the right side of the furnace cabinet. The
locating dimple is 1 7/8” measured from the front edge
of the cabinet in line with the knock out. To use the
alternate combustion air location:
1. Remove screws and combustion air flange from cabinet.
2. Insert cabinet plug in unused combustion air hole.
3. Drill a pilot hole at the cabinet dimple (size dictated by
knockout tool used).
4. Use a knockout tool to create a 3” diameter hole
5. Install combustion air flange and secure with screws
removed in step one.
6. Install screws removed in step 1 securing flange to
cabinet.
1
2
3
4
5
6
7
8
2
120
115
110
105
100
95
90
85
3
134
127
120
113
106
99
92
85
2
100
95
90
85
80
75
70
65
3
151
144
137
130
123
116
109
102
2
45
40
35
30
25
20
15
10
3
113
106
99
92
85
78
71
64
2
70
65
60
55
50
45
N/A
N/A
3
89
82
75
68
61
54
47
40
2
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
3
120
113
106
99
92
85
78
71
2
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
3
151
144
137
130
123
116
109
102
2
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
3
151
144
137
130
123
116
109
102
2
120
115
110
105
100
95
N/A
N/A
3
185
178
171
164
157
150
143
136
2
85
80
75
70
65
60
55
50
3
168
161
154
147
140
133
126
119
2
40
35
30
25
20
15
10
5
3
120
113
106
99
92
85
78
71
2
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
3
113
106
99
92
85
78
71
64
2
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
3
151
144
137
130
123
116
109
102
*MV96C0403BN
*MVC96/*CVC96 Direct Vent (2 - Pipe) and Non-Direct Vent (1- Pipe)
(6)
Maximum Allowable Length of Vent/Flue Pipe
MODEL
Pipe Size
(4)
(in.)
Number of Elbows
(3) (5)
*CVC960603BN
*CVC960804CN
*CVC961005CN
*CVC961205DN
*MVC960603BN
*MVC960803BN
*MVC960804CN
*MVC961005CN
*MVC961205DN
*CVC960403BN
*MVC961005DN
Non-Direct Vent (Single Pipe) Piping
Non-direct
vent
installations require only a vent/flue pipe. The
vent pipe can be run horizontally with an exit through the side
of the building or run vertically with an exit through the roof
of the building. The vent can also be run through an existing
unused
chimney; however, it must extend a minimum of 12
inches above the top of the chimney. The space between the
vent pipe and the chimney must be closed with a weather-
tight, corrosion-resistant flashing.
Although
non-direct
vent
installations do not require a
combustion air intake
pipe
, a minimum of one 90° elbow
should be attached to the furnace’s combustion air intake
if
:
an upright installation uses the standard intake location, or a
horizontal installation uses the alternate air intake location.
This elbow will guard against inadvertent blockage of the air
intake.
