49
Connecting the Gas Supply
4.1 Gas Pipe Sizing Tables
The following tables are referenced from 2012 National Fuel Gas Code for reference only. Please consult the gas pipe manufacturer for actual
pipe capacities.
Maximum Natural Gas Delivery Capacity
In Cubic Feet (ft
3
) per Hour (0.60 Specific Gravity; 0.5 in WC Pressure Drop). Contact your gas supplier for BTU/ft
3
ratings. Use 1,000 BTU/ft
3
for
simplified calculations. This table is recommended for supply pressures less than 6 in WC.
Pipe Size
Length (including fittings)
10 ft
(3 m)
20 ft
(6 m)
30 ft
(9 m)
40 ft
(12 m)
50 ft
(15 m)
60 ft
(18 m)
70 ft
(21 m)
80 ft
(24 m)
90 ft
(27 m)
100 ft
(30 m)
125 ft
(38 m)
3
/
4
in
360
247
199
170
151
137
126
117
110
104
92
1 in
678
466
374
320
284
257
237
220
207
195
173
1
1
/
4
in
1,390
957
768
657
583
528
486
452
424
400
355
1
1
/
2
in
2,090
1,430
1,150
985
873
791
728
677
635
600
532
2 in
4,020
2,760
2,220
1,900
1,680
1,520
1,400
1,300
1,220
1,160
1,020
2
1
/
2
in
6,400
4,400
3,530
3,020
2,680
2,430
2,230
2,080
1,950
1,840
1,630
3 in
11,300
7,780
6,250
5,350
4,740
4,290
3,950
3,670
3,450
3,260
2,890
4 in
23,100
15,900
12,700
10,900
9,660
8,760
8,050
7,490
7,030
6,640
5,890
In Cubic Feet (ft
3
) per Hour (0.60 Specific Gravity; 3.0 in WC Pressure Drop). Contact your gas supplier for BTU/ft
3
ratings. Use 1,000 BTU/ft
3
for
simplified calculations. This table is recommended for supply pressures of 6 in WC or greater.
Pipe Size
Length (including fittings)
10 ft
(3 m)
20 ft
(6 m)
30 ft
(9 m)
40 ft
(12 m)
50 ft
(15 m)
60 ft
(18 m)
70 ft
(21 m)
80 ft
(24 m)
90 ft
(27 m)
100 ft
(30 m)
125 ft
(38 m)
3
/
4
in
949
652
524
448
397
360
331
308
289
273
242
1 in
1,787
1,228
986
844
748
678
624
580
544
514
456
1
1
/
4
in
3,669
2,522
2,025
1,733
1,536
1,392
1,280
1,191
1,118
1,056
936
1
1
/
2
in
5,497
3,778
3,034
2,597
2,302
2,085
1,919
1,785
1,675
1,582
1,402
2 in
10,588
7,277
5,844
5,001
4,433
4,016
3,695
3,437
3,225
3,046
2,700
2
1
/
2
in
16,875
11,598
9,314
7,971
7,065
6,401
5,889
5,479
5,140
4,856
4,303
3 in
29,832
20,503
16,465
14,092
12,489
11,316
10,411
9,685
9,087
8,584
7,608
4 in
43,678
30,020
24,107
20,632
18,286
16,569
15,243
14,181
13,305
12,568
11,139
Summary of Contents for NHB Series
Page 120: ...120 Appendixes 12 6 Component Assembly Diagrams and Part Lists 12 6 1 Case Assembly NFB 301C...
Page 122: ...122 Appendixes 12 6 2 Case Assembly NFB 399C...
Page 124: ...124 Appendixes 12 6 3 Heat Exchanger and Waterway Assembly NFB 301C...
Page 126: ...126 Appendixes 12 6 4 Heat Exchanger and Waterway Assembly NFB 399C...
Page 128: ...128 Appendixes 12 6 5 Combustion Parts Assembly NFB 301C...
Page 131: ...131 Appendixes 12 6 6 Combustion Parts Assembly NFB 399C...
Page 134: ...Memo...
