Gas PipingQuestion 86 of 120
The same 175,000 Btu/h total connected load is served by LP-gas instead of natural gas. Using about 2,500 Btu per cubic foot for propane, what flow must the piping carry?
a.70 cfh
b.175 cfh
c.437 cfh
d.44 cfh
Explanation
For propane, cfh equals Btu/h divided by 2,500, so 175,000 / 2,500 = 70 cfh. 175 cfh is the natural gas answer using 1,000 Btu/cu ft; 437 cfh comes from multiplying instead of dividing by 2.5; 44 cfh comes from using a heating value near 4,000, which no common fuel gas has.
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