Westinghouse WBRU 100W Series, Installation, Start-Up And Maintenance Instructions

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WHL-032 REV. 6.2.16
A. ADDITIONAL PRECAUTION FOR EXCESS FLOW VALVE (EFV)
If an excess flow valve (EFV) is in the gas line, check the manufacturer’s minimum and
maximum flow capacity ratings. An improperly sized EFV will not allow for a full flow of
gas to the boiler and will cause the boiler to malfunction.
B. GAS PIPE SIZING TABLES
1. Gas Pipe Sizing
This information is for reference use only. Refer to gas pipe manufacturer specifications
for actual delivery capacity. The DOE standard for Natural Gas is 1100 BTU/ft
3
. Contact
the local gas supplier for actual BTU/ft
3
rating.
2. Natural Gas Pipe Sizing
The following tables list maximum capacity of pipe in cubic feet of gas per hour for gas
pressures of 14” or less and a pressure drop of 0.5 inches water column, based on a 0.60 specific gravity for natural gas.
Maximum Natural Gas Delivery Capacity
– Length of Corrugated Stainless Steel Pipe in Feet
Pipe Size
Cubic Feet per Hour (0.60 Specific Gravity, 0.5 WC Pressure Drop)
10 20 30 40 50 60 80 100 150 200
¾”
192 137 112 97 87 80 69 62 48 44
1”
383 269 218 188 168 153 132 118 91 82
1 ¼”
639 456 374 325 292 267 232 208 171 148
1 ½”
1260 888 723 625 559 509 440 393 320 277
2”
2930 2080 1700 1470 1320 1200 1040 933 762 661
Table 11
– Natural Gas Delivery Capacity – Corrugated Stainless Steel Pipe – Refer to ANSI Z223.1 – National Fuel Gas Code,
Latest Edition
Maximum Natural Gas Delivery Capacity
– Length of Black Iron Pipe (Sch. 40 Metallic) in Feet
Pipe Size
Cubic Feet per Hour (0.60 Specific Gravity, 0.5 WC Pressure Drop)
10 20 30 40 50 60 80 100 150 200
¾”
360 247 199 170 151 137 117 104 83 71
1”
678 466 374 320 284 257 220 195 157 134
1 ¼”
1390 957 768 657 583 528 452 400 322 275
1 ½”
2090 1430 1150 985 873 791 677 600 482 412
2”
4020 2760 2220 1900 1680 1520 1300 1160 928 794
2 ½”
6400 4400 3530 3020 2680 2430 2080 1840 1480 1270
3”
11300 7780 6250 5350 4740 4290 3670 3260 2610 2240
4”
23100 15900 12700 10900 9660 8760 7490 6640 5330 4560
Table 12
– Natural Gas Delivery Capacity – Black Iron Pipe – Refer to ANSI Z223.1 – National Fuel Gas Code, Latest Edition
3. LP (Liquid Propane) Gas Pipe Sizing
The following is intended for use for piping between a Single or Second Stage (Low Pressure) Regulator and the water heater. The
following tables list maximum capacity of pipe in cubic feet of gas per hour for an inlet pressure of 11 inches water column and specific
pressure drop of 0.5 inches water column based on 1.5 specific gravity for liquid propane.
Maximum Liquid Propane Delivery Capacity
– Length of Corrugated Stainless Steel Pipe in Feet
Pipe Size
Cubic Feet per Hour (0.60 Specific Gravity, 0.5 WC Pressure Drop)
10 20 30 40 50 60 80 100 150 200
¾”
303 216 177 153 137 126 109 98 75 69
1”
605 425 344 297 265 241 208 186 143 129
1 ¼”
971 661 528 449 397 359 307 270 217 183
1 ½”
1990 1400 1140 988 884 805 696 621 506 438
2”
4640 3290 2680 2330 2080 1900 1650 1480 1210 1050
Table 13
– Liquid Propane Delivery Capacity – Corrugated Stainless Steel Pipe – Refer to ANSI Z223.1 – National Fuel Gas
Code, Latest Edition
Figure 17
– Excess Flow Valve (EFV)