Gas PipingQuestion 254 of 360
A branch serves two appliances downstream: a 30,000 BTU/hr wall heater and a 120,000 BTU/hr furnace. In natural gas cfh, what demand governs that branch?
a.150 cfh
b.120 cfh
c.30 cfh
d.90 cfh
Explanation
Add the two inputs, 30,000 plus 120,000 equals 150,000 BTU/hr, then divide by 1,000 to get 150 cfh of natural gas demand. That combined cfh is what the branch must carry at the design pressure drop. Sections closer to just one appliance carry only that appliance's demand.
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