Core TradesCâu 96 / 700
CALCULATION: A common rule of thumb provides 1 square inch of combustion air opening per 1,000 Btu/h of appliance input when air comes from inside a large space. For a 100,000 Btu/h furnace using two openings (high and low), what free area does EACH opening need under this rule?
a.50 square inches each
b.75 square inches each
c.100 square inches each
d.200 square inches each
Giải thích
Total required = 100,000 / 1,000 = 100 square inches, and each of the two openings (high and low) typically must provide the full required area, so each is about 100 square inches. Answers 50 and 75 undersize the openings; 200 doubles unnecessarily.
Trích dẫn luật: 2025 CA Mechanical CodeLuyện miễn phí toàn bộ 700 câu hỏi — không cần đăng ký.
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