Gas & FuelCâu 71 / 110
Using the known-air-infiltration method, an appliance space of 10,000 ft^3 is credited with 0.35 air changes per hour of natural infiltration. How many cubic feet of infiltration air per hour does the space provide?
a.350 cfh
b.1,750 cfh
c.3,500 cfh
d.35,000 cfh
Giải thích
Infiltration air = volume x air changes per hour = 10,000 x 0.35 = 3,500 cubic feet per hour. This method credits only the air that leaks through a standard building, which in a tight modern house is often too little for the appliance load. When it is insufficient, dedicated outdoor combustion air must be supplied.
Trích dẫn luật: IFGC §304.5Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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