Nitrogen Pressure Test (Temperature-Corrected)

Separates a real leak from the thermal swing in a standing nitrogen pressure test using Gay-Lussac's law (P/T constant at fixed volume, absolute units): the temperature-corrected expected gauge pressure, the pressure lost below it to a leak, and a holds / leak verdict against an editable tolerance.

Gay-Lussac at constant volume: expected_psig = (start_psig + atm) x (T2_R / T1_R) - atm, with T_R = T_F + 459.67. leak_drop_psi = expected_psig - end_psig (positive = lost below the temperature-corrected value = leak); within +/- tolerance is a thermal-only hold.

First-principles Gay-Lussac's law (ideal gas at constant volume, public physics); the standing nitrogen pressure test with temperature correction is standard refrigeration leak-check practice (by name).

The P/T = constant gas law is public physics; the test pressure and tolerance are editable field values.

Estimate. AHJ and licensed professional govern.

Field names used by the API: start_psig, start_temp_F, end_temp_F, end_psig, atm_psi, tolerance_psi, expected_psig, leak_drop_psi, gauge_change_psi

• Absolute units pressures in psia = psig + atmospheric (default 14.7); temperatures in Rankine = F + 459.67first principles
• Constant volume the system volume is fixed over the hold, so P/T is constant (Gay-Lussac)ideal-gas law
• Tolerance default +/-1 psi band on the leak figure (editable); read both temperatures at the same point on the systemfield practice