Design & SizingCâu 14 / 110
A natural-gas furnace is rated at 120,000 BTU/hr. Natural gas has a heating value of about 1,000 BTU per cubic foot. What gas volume flow, in cubic feet per hour (cfh), must the piping deliver?
a.12 cfh
b.120 cfh
c.60 cfh
d.1,200 cfh
Giải thích
cfh = BTU/hr load / heating value = 120,000 / 1,000 = 120 cfh. Because natural gas is roughly 1,000 BTU per cubic foot, the cfh figure is simply the input in thousands of BTU. This cfh value is what you carry into the gas-pipe sizing table with the longest run.
Trích dẫn luật: UPC §610.0Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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