Navien NHB H Series User Manual

49Connecting the Gas Supply
4.1 Gas Pipe Sizing Tables
The following tables are referenced from the 2021 National Fuel Gas Code and are 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)
1
/
2
in 454 312 250 214 190 172 158 147 138 131 116
3
/
4
in 949 652 524 448 397 360 331 308 289 273 242
1 in 1,790 1,230 986 844 748 678 624 580 544 514 456
1
1
/
4
in 3,670 2,520 2,030 1,730 1,540 1,390 1,280 1,190 1,120 1,060 936
1
1
/
2
in 5,500 3,780 3,030 2,600 2,300 2,090 1,920 1,790 1,670 1,580 1,400
2 in 10,600 7,280 5,840 5,000 4,430 4,020 3,690 3,440 3,230 3,050 2,700
2
1
/
2
in 16,900 11,600 9,310 7,970 7,060 6,400 5,890 5,480 5,140 4,860 4,300
3 in 29,800 20,500 16,500 14,100 12,500 11,300 10,400 9,690 9,090 8,580 7,610
4 in 60,800 41,800 33,600 28,700 25,500 23,100 21,200 19,800 18,500 17,500 15,500

Navien NHB H Series Specifications

General

Brand	Navien
Model	NHB H Series
Category	Boiler
Language	English