Design & SizingQuestion 15 of 110
A house has three natural-gas appliances: a 100,000 BTU/hr furnace, a 40,000 BTU/hr water heater, and a 65,000 BTU/hr range. Using 1,000 BTU per cubic foot, what total cfh must the gas meter and main serve?
a.165 cfh
b.240 cfh
c.205 cfh
d.2,050 cfh
Explanation
Total input = 100,000 + 40,000 + 65,000 = 205,000 BTU/hr, and at 1,000 BTU per cubic foot that is 205 cfh. The whole-house demand sizes the meter and the main from the meter to the first tee. Individual branches are then sized for the appliance each one serves.
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