15
MODEL
PIPE
SIZE
1
2
3
4
5
6
7
8
2
75
70
65
60
55
50
45
40
3
114
107
100
93
86
79
72
65
2
45
40
35
30
25
20
15
10
3
168
161
154
147
140
133
126
119
2
35
30
25
20
15
10
5
N/A
3
168
161
154
147
140
133
126
119
2
60
55
50
45
40
35
30
25
3
113
106
99
92
85
78
71
64
2
45
40
35
30
25
20
15
10
3
120
113
106
99
92
85
78
71
2
40
35
30
25
20
15
10
5
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
158
151
144
137
130
123
116
109
2
100
95
90
85
80
75
70
65
3
137
130
123
116
109
102
95
88
2
45
40
35
30
25
20
15
10
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
110
103
96
89
82
75
68
61
*M9S960803BN - add 20' of 2" pipe for upflow position
7,000 ft altitude or above use 3" pipe
1) Maximum allowable limits listed on individual lengths for inlet and flue and NOT a
combination
2) Minimum requirement for each vent pipe is five (5) feet in length and one elbow/tee
3) Tee used in the vent/flue termination must be included when determining the number
of elbows in the piping system.
4) 2 1/2" or 3" diameter pipe can be used in place of 2" diameter pipe
Number of Elbows
*M9S960403AN
*M9S961005CN
*M9S961205DN
*M9S960603BN
*M9S960803BN
*M9S960804CN
*M9S960805CN
*C9S960403BN
*C9S960603BN
*C9S960804CN
*C9S961005CN
*C9S961205DN
Table 4
MODEL
PIPE
SIZE
1
2
3
4
5
6
7
8
2
75
70
65
60
55
50
45
40
3
114
107
100
93
86
79
72
65
2
55
50
45
40
35
30
25
20
3
127
120
113
106
99
92
85
78
2
30
25
20
15
10
5
N/A
N/A
3
72
65
58
51
44
37
30
23
2
30
25
20
15
10
5
N/A
N/A
3
72
65
58
51
44
37
30
23
2
40
35
30
25
20
15
10
5
3
72
65
58
51
44
37
30
23
2
60
55
50
45
40
35
30
25
3
168
161
154
147
140
133
126
119
2
30
25
20
15
10
5
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
65
58
51
44
37
30
23
16
7,000 ft altitude or above use 3" pipe
*M9S920803BN - add 10' of 2" pipe for up flow position, add 66' of 3" pipe for up flow
position
*M9S920804CN - add 25' of 2" pipe for up flow position, add 58' of 3" pipe for up flow
position
*M9S920805CN - add 15' of 2" pipe fpr upflow position, add 58' of 3" pipe for upflow
position
1) Maximum allowable limits listed on individual lengths for inlet and flue and NOT a
combination
2) Minimum requirement for each vent pipe is five (5) feet in length and one elbow/tee
3) Tee used in the vent/flue termination must be included when determining the number
of elbows in the piping system.
Number of Elbows
*M9S920403AN
*M9S920603BN
*M9S920803BN
*M9S920804CN
*M9S920805CN
*M9S921004CN
*M9S921005CN
*M9S921205DN
Table 5
1. Maximum allowable limits listed on individual lengths
for inlet and flue and NOT a combination.
2.
Minimum requirement for each vent pipe if five (5)
feet in length and one elbow/tee.
3.
Tee used in the vent/flue termination must be
included when determining the number of elbows in
the piping system.
4. 2 ½” or 3” diameter pipe can be used in place of 2”
diameter pipe.
5.
Increased Clearance Configuration using (2) 45
deg. Long Sweep elbows should be considered
equivalent to one 90 deg. elbow.
6.
One 90° elbow should be secured to the combustion
air intake connection.
Vent Pipe Connection
The vent pipe outlet is sized to accept 2” pipe. Secure vent
pipe directly into the furnace fitting with the appropriate
glue. Alternately, a small section of 2” pipe may be glued
in the furnace socket and a rubber coupling installed to
allow removal for future service. Piping should be routed in
a manner to avoid contact with refrigerant lines, metering
devices, condensate drain lines, etc. If necessary,
clearances may be increased by creating an offset using
two 45° elbows (Figure 7).
45 DEGREE
ELBOWS
Increased Clearance Configuration
Figure 7
COMBUSTION AIR PIPE CONNECTION
If the furnace is being installed without a combustion air
pipe, a 90° elbow should be used on the combustion air
intake to guard against blockage.
On up flow / horizontal models, secure the combustion
air intake pipe to the air intake coupling using a rubber
coupling supplied with the furnace. The rubber coupling
may be omitted by inverting the intake coupling and gluing
pipe directly to it. Piping may also be glued to the intake
coupling in its original position by using a plastic coupling.
On counterflow units secure the combustion air intake
pipe to the air intake coupling using the rubber coupling
and worm gear hose clamps provided with the unit. The
counterflow rubber coupling allows service removal of air
intake piping internal to the furnace blower compartment.
The combustion air intake pipe can also be secured
directly to the counterflow unit air intake pipe coupling.
