NOTICE
USA boilers built for installation at altitudes greater than 2,000 feet above sea level have been specially orificed to reduce gas input rate 4 percent per 1,000 feet above sea level per the National Fuel Gas Code, ANSI Z223.1, Section 8.1.2 and Appendix F. Canadian boilers' orifice siz ing is indicated on the rating label. High altitude boiler models are identifiable by the model number suffix "H" on the rating label.
Table 4: Fitting Equivalent Lengths
Fitting |
| Nominal Pipe Size |
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½ |
| ¾ | 1 |
| 1¼ | |
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45° Ell | 0.7 |
| 1 | 1.2 |
| 1.6 |
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90° Ell | 1.6 |
| 2.1 | 2.6 |
| 3.5 |
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Tee (As Elbow) | 3.1 |
| 4.1 | 5.2 |
| 6.9 |
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C.Pressure test. The boiler and its gas connection must be leak tested before placing boiler in operation.
1. Protect boiler gas control valve. For all testing over ½ psig, boiler and its individual shutoff valve must be disconnected from gas supply piping. For testing at ½ psig or less, isolate boiler from gas supply piping by closing boiler's individual manual shutoff valve.
Table 5: Specific Gravity Correction Factors
Specific | Correction | Specific | Correction |
Gravity | Factor | Gravity | Factor |
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0.50 | 1.10 | 1.30 | 1.07 |
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0.55 | 1.04 | 1.40 | 1.04 |
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0.60 | 1.00 | 1.50 | 1.00 |
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0.65 | 0.96 | 1.60 | 0.97 |
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0.70 | 0.93 | 1.70 | 0.94 |
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0.75 | 0.90 |
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0.80 | 0.87 |
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2.Locate leaks using approved combustible gas detector, soap and water, or similar nonflammable solution. Do not use matches, candles, open flames, or other ignition source.
Figure 8: Recommended Gas Piping
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