Gas Pipe Sizing Calculator (NFPA 54)
What pressure drop does NFPA 54 allow?
For 2-PSI or less systems, 0.5" W.C. pressure drop is typical. For 2-PSI systems with a regulator at the appliance, larger drops (1.0" W.C. or 1.0 PSI on the high side) are allowed. The calculator defaults to 0.5" W.C., the most common residential design pressure drop.
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Use the Gas Pipe Sizing Calculator (NFPA 54) to get an exact answer for your inputs.
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