Gas & FuelQuestion 110 of 110
A natural-gas dryer needs 35,000 BTU/hr and a range needs 65,000 BTU/hr on a shared branch. Using 1,000 BTU/ft^3, what is the combined cfh the common branch must carry?
a.35 cfh
b.100 cfh
c.65 cfh
d.1,000 cfh
Explanation
Combined input = 35,000 + 65,000 = 100,000 BTU/hr, and at 1,000 BTU per cubic foot that is 100 cfh on the shared branch. The common section always carries the sum of the downstream appliance demands. Each appliance's own connector is then sized for only its individual load.
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