Gas & Fuel第 60 / 110 题
An appliance room contains a 120,000 BTU/hr furnace and a 40,000 BTU/hr water heater drawing combustion air from inside. Using the rule of 50 cubic feet of room volume per 1,000 BTU/hr for indoor air, what minimum room volume is required?
a.4,000 ft^3
b.12,000 ft^3
c.16,000 ft^3
d.8,000 ft^3
解析
Total input = 120,000 + 40,000 = 160,000 BTU/hr, and at 50 ft^3 per 1,000 BTU/hr the room needs 160 x 50 = 8,000 ft^3. If the space is smaller than this, combustion air must be brought in from outdoors through sized openings. Adequate combustion air prevents oxygen depletion and dangerous incomplete combustion.
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