VI. Gas Piping
WARNING
Failure to properly pipe gas supply to boiler may result in improper operation and damage to the boiler or structure. Always assure gas piping is absolutely leak free and of the proper size and type for the connected load.
An additional gas pressure regulator may be needed. Consult gas supplier.
A.Size gas Piping. Design system to provide adequate gas supply to boiler. Consider these factors:
1.Allowable pressure drop from point of delivery to boiler. Maximum allowable system pressure is ½ psig. Actual point of delivery pressure may be less; contact gas supplier for additional information. Minimum gas valve inlet pressure is indicated on Rating Label, located on the vestibule panel.
2.Maximum gas demand. Table 2 lists boiler input rate. Also consider existing and expected future gas utilization equipment (i.e. water heater, cooking equipment).
Table 2: Rated Input
Boiler | Rated Capacity | Gas | ||
Model | [cubic feet per hour] | Connection | ||
Number |
|
| Size | |
Natural | LP/Propane | |||
|
| |||
|
|
|
| |
IN3 | 62 | 24¾ | ½ | |
|
|
|
| |
IN4 | 105 | 42 | ½ | |
|
|
|
| |
IN5 | 140 | 56 | ½ | |
|
|
|
| |
IN6 | 175 | 70 | ½ | |
|
|
|
| |
IN7 | 210 | 84 | ¾ | |
|
|
|
| |
IN8 | 245 | 98 | ¾ | |
|
|
|
| |
IN9 | 280 | 112 | ¾ | |
|
|
|
| |
IN10 | 315 | 126 | ¾* | |
|
|
|
| |
IN11 | 349 | 139½ | ¾* | |
|
|
|
| |
IN12 | 385 | 154 | 1 | |
|
|
|
|
*Gas connection size is 1" on IN10 and IN11 Continuous Ignition (Standing Pilot)
3.Length of piping and number of fittings. Refer to
Table 3 for maximum capacity of Schedule 40 pipe.
Table 4 lists equivalent length for standard fittings.
4.Corrections for the specific gravity of natural gas can be found in Table 5.
For materials or conditions other than those listed above, refer to the National Fuel Gas Code, NFPA 54/ ANSI Z223.1 and/or CAN/CSA B149.1. Installation Codes, or size system using standard engineering methods acceptable to authority having jurisdiction.
WARNING
Failure to use proper thread compounds on all gas connectors may result in leaks of flammable gas.
WARNING
Gas supply to boiler and system must be absolutely shut off prior to installing or servicing boiler gas piping.
B.Connect boiler gas valve to gas supply system.
1.Use methods and materials in accordance with local plumbing codes and requirements of gas supplier. In absence of such requirements, follow the National Fuel Gas Code, NFPA 54/ANSI Z223.1 and/or CAN/CSA B149.1 Installation Codes.
2.Use thread (joint) compounds (pipe dope) resistant to action of liquefied petroleum gas.
3.Install sediment trap,
Figure 29: Recommended Gas Piping
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