Gas PipingQuestion 226 of 360
A natural gas furnace is rated at 100,000 BTU/hr input. Using a heating value of 1,000 BTU per cubic foot, what gas demand in cubic feet per hour (cfh) must the piping supply?
a.100 cfh
b.10 cfh
c.1,000 cfh
d.10,000 cfh
Explanation
Divide the BTU/hr input by the heating value: 100,000 divided by 1,000 equals 100 cubic feet per hour. This cfh demand is the number you carry into the gas pipe sizing tables. Natural gas is commonly figured at about 1,000 BTU per cubic foot.
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