| 25
Installation Instructions
Singular Combi Boiler - BTC 439003301 B (2021/07)
5 Connecting the Gas Supply
5.1 Gas Pipe Sizing Tables
Gas pipe sizing is based on the gas type, supplied gas pressure, pressure drop in
the system, and gas line type. The tables below are for reference only (when the
gas supply is piping straight to the boiler with no connections to any other gas
appliances). For gas pipe sizing, refer to the latest National Fuel Gas code, NFPA 54
and consult the gas pipe manufacturer for actual gas pipe capacities.
Natural Gas
Maximum Capacity of Natural Gas Based on a 0.60 specifi c gravity at a 0.5" WC
pressure drop.
Pipe Size kBTU/H of Natural Gas
Length 10' 20' 30' 40' 50' 60' 70' 80' 90' 100' 125' 150' 200'
3/4" 360 247 199 170 151 137 126 117 110 104 92 83 71
1" 678 466 374 320 284 257 237 220 207 195 173 157 134
1 1/4" 1390 957 768 657 583 528 486 452 424 400 355 322 275
1 1/2" 2090 1430 1150 985 873 791 728 677 635 600 532 482 412
2" 4020 2760 2220 1900 1680 1520 1400 1300 1220 1160 1020 928 794
2 1/2" 6400 4400 3530 3020 2680 2430 2230 2080 1950 1840 1630 1480 1270
3" 11300 7780 6250 5350 4740 4290 3950 3670 3450 3260 2890 2610 2240
4" 23100 15900 12700 10900 9660 8760 8050 7490 7030 6640 5890 5330 4560
Table 6 For less than 6" WC supply pressure.
Maximum Capacity of Natural Gas Based on a 0.60 specifi c gravity at a 3.0" WC
pressure drop.
Pipe Size kBTU/H of Natural Gas
Length 10' 20' 30' 40' 50' 60' 70' 80' 90' 100' 125' 150' 200'
1/2" 454 312 250 214 190 172 158 147 138 131 116 105 90
3/4" 949 652 524 448 397 360 331 308 289 273 242 219 188
1" 1790 1230 986 844 748 678 624 580 544 514 456 413 353
1 1/4" 3670 2520 2030 1730 1540 1390 1280 1190 1120 1060 936 848 726
1 1/2" 5500 3780 3030 2600 2300 2090 1920 1790 1670 1580 1400 1270 1090
2" 10600 7280 5840 5000 4430 4020 3690 3440 3230 3050 2700 2450 2090
2 1/2" 16900 11600 9310 7970 7060 6400 5890 5480 5140 4860 4300 3900 3340
3" 29800 20500 16500 14100 12500 11300 10400 9690 9090 8580 7610 6890 5900
4" 60800 41800 33600 28700 25500 23100 21200 19800 18500 17500 15500 14100 12000
Table 7 For 6" WC or greater supply pressure.
Liquid Propane Gas
Maximum Capacity of propane (LP) Gas Based on 11" WC supply pressure at a 0.5"
WC pressure drop.
Pipe Size kBTU/H of Propane Gas
Length 10' 20' 30' 40' 50' 60' 80' 100' 125' 150' 175' 200' 250'
1/2" 291 200 160 137 122 110 101 94 89 84 74 67 62
3/4" 608 418 336 287 255 231 212 197 185 175 155 140 129
1" 1150 787 632 541 480 434 400 372 349 330 292 265 243
1 1/4" 2350 1620 1300 1110 985 892 821 763 716 677 600 543 500
1 1/2" 3520 2420 1940 1660 1480 1340 1230 1140 1070 1010 899 814 749
2" 6790 4660 3750 3210 2840 2570 2370 2200 2070 1950 1730 1570 1440
Table 8
To Next Page
Loading...
Need help?
General