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TABLE 5
Vent Connector Capacity
Type B Double−Wall Vents with Type B Double−Wall Connectors
Serving Two or More Category I Appliances
Vent
Connector
Vent and Connector Diameter − D (inches)
Vent
Height
Connector
Rise
3 Inch
4 Inch
5 Inch
6 Inch
Height
H
(feet)
Rise
R
(feet)
Appliance Input Rating in Thousands of Btu Per Hour
(feet)
(feet)
MIN
MAX
MIN
MAX
MIN
MAX
MIN
MAX
1
22
37
35
66
46
106
58
164
6
2
23
41
37
75
48
121
60
183
6
3
24
44
38
81
49
132
62
199
1
22
40
35
72
49
114
64
176
8
2
23
44
36
80
51
128
66
195
3
24
47
37
87
53
139
67
210
1
22
43
34
78
49
123
65
189
10
2
23
47
36
86
51
136
67
206
3
24
50
37
92
52
146
69
220
1
21
50
33
89
47
142
64
220
15
2
22
53
35
96
49
153
66
235
3
24
55
36
102
51
163
68
248
1
21
54
33
99
46
157
62
246
20
2
22
57
34
105
48
167
64
259
3
23
60
35
110
50
176
66
271
1
20
62
31
113
45
181
60
288
30
2
21
64
33
118
47
190
62
299
3
22
66
34
123
48
198
64
309
TABLE 6
Common Vent Capacity
Type B Double−Wall Vents with Type B Double−Wall Connectors
Serving Two or More Category I Appliances
Vent
Common Vent Diameter − D (inches)
Vent
Height
4 Inch
5 Inch
6 Inch
7 Inch
Height
H
(feet)
Appliance Input Rating in Thousands of Btu Per Hour
(feet)
FAN + FAN
FAN + NAT
FAN + FAN
FAN + NAT
FAN + FAN
FAN + NAT
FAN + FAN
FAN + NAT
6
92
81
140
116
204
161
309
248
8
101
90
155
129
224
178
339
275
10
110
97
169
141
243
194
367
299
15
125
112
195
164
283
228
427
352
20
136
123
215
183
314
255
475
394
30
152
138
244
210
361
297
547
459
