Gas & Fuel第 72 / 110 题
A gas appliance vent connector runs 12 ft horizontally to the chimney. Code requires a minimum upward rise of 1/4 in per foot toward the chimney. What total vertical rise must the connector have?
a.1-1/2 in
b.6 in
c.12 in
d.3 in
解析
Rise = 1/4 in per ft x 12 ft = 3 in of upward slope from the appliance to the chimney. The rise keeps hot flue gas moving upward and prevents it from stalling and spilling back into the room. A level or downward-sloped connector defeats natural draft and can spill carbon monoxide.
法律依据: IFGC §503.6免费刷完整 110 道题库 — 无需注册。
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