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    Fixture Unit Calculator (DFU / WSFU)

    How do I convert fixture units to GPM?

    Use Hunter’s curve (the IPC water-supply demand chart): fixture-unit totals are converted to probable simultaneous demand in GPM, because not every fixture runs at once. Roughly, 10 WSFU is about 8 GPM and 100 WSFU is about 44 GPM, but the curve is nonlinear — read it from the code table rather than scaling linearly.

    Run the numbers for your project

    Use the Fixture Unit Calculator (DFU / WSFU) to get an exact answer for your inputs.

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    Related questions

    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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