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HVAC & Piping

HVAC and piping calculators.

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Gas Pipe Size Calculator

Size natural gas or propane pipe with the NFPA 54 / IFGC longest-length method. Enter the total BTU load and the longest run to get the minimum Schedule 40 pipe size and its capacity in CFH. Free, no sign-up.

HVAC & Piping
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Drainage Fixture Unit (DFU) Calculator

Size sanitary drainage pipe from drainage fixture units. Add fixtures to total the DFU load, then get the minimum building drain, branch, or stack size per IPC Table 710.1. Free, no sign-up.

HVAC & Piping
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Drain Slope Calculator

Calculate drain pipe slope for DWV and sewer lines. Find the total fall from a run and pitch, or the slope from a measured drop, and check it against the IPC minimum grade by pipe size. Free, no sign-up.

HVAC & Piping
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