Gas & FuelQuestion 73 of 110
A two-appliance system: appliance A needs 60 cfh and appliance B needs 40 cfh. Using the longest-length method, the section of pipe between the meter and the first tee carries what demand?
a.100 cfh
b.40 cfh
c.60 cfh
d.20 cfh
Explanation
The common section upstream of the first tee carries the sum of all downstream demand, 60 + 40 = 100 cfh, and is sized for that total at the system's longest length. Each branch downstream of the tee is then sized for only the appliance it serves. Undersizing the common section starves both appliances during simultaneous use.
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