5
Gas piping (continued)
Natural Gas:
Pipe sizing for natural gas
1.Refer to Table 4 for pipe length and diameter. Base on rated boiler input (divide by 1,000 to obtain cubic feet per hour).
a.Table 4 is only for natural gas with specific gravity 0.60, with a pressure drop through the gas piping of 0.30" w.c.
b.For additional gas pipe sizing information, refer to ANSI Z223.1 (or B149.1 or B149.2 for Canadian installations).
Natural gas supply pressure requirements
1.Pressure required at gas valve inlet pressure port:
•Maximum: 13" w.c. with no flow (lockup) or with boiler on
•Minimum: 5" w.c. with gas flowing (verify during boiler startup, while boiler is at high fire)
2.Install 100% lockup gas pressure regulator in supply line if inlet pressure can exceed 13" w.c. at any time. Adjust lockup regulator for 13" w.c. maximum.
Propane Gas:
Ultra boilers are shipped ready to fire natural gas ONLY (exception:
Pipe sizing for natural gas
1.Contact gas supplier to size pipes, tanks and 100% lockup gas pressure regulator.
Propane supply pressure requirements
1.Adjust propane supply regulator provided by gas supplier for 13" w.c. maximum pressure.
2.Pressure required at gas valve inlet pressure port:
•Maximum: 13" w.c. with no flow (lockup) or with boiler on
•Minimum: 4" w.c. with gas flowing (verify during boiler startup, while boiler is at high fire)
Table 4 Pipe capacity for 0.60 specific gravity natural gas
| Gas pipe |
| Capacity of pipe for pipe size of: |
| ||
| (Capacity in cubic feet gas per hour) |
| |||
| length |
|
| |||
|
|
|
|
| |
(feet) | ½" | ¾" | 1" | 1¼" | 1½" |
| |||||
|
|
|
|
|
|
10 | 132 | 278 | 520 | 1050 | 1600 |
|
|
|
|
|
|
20 | 92 | 190 | 350 | 730 | 1100 |
|
|
|
|
|
|
30 | 73 | 152 | 285 | 590 | 860 |
|
|
|
|
|
|
40 | 63 | 130 | 245 | 500 | 760 |
|
|
|
|
|
|
50 | 56 | 115 | 215 | 440 | 670 |
|
|
|
|
|
|
75 | 45 | 93 | 175 | 360 | 545 |
|
|
|
|
|
|
100 | 38 | 79 | 150 | 305 | 460 |
|
|
|
|
|
|
150 | 31 | 64 | 120 | 250 | 380 |
|
|
|
|
|
|
22 | Part number |
