A small pressure change does not always mean a leak. Before a decision is made, temperature, stabilization, instrument accuracy, and the volume of the tested section must be evaluated.
Temperature
Even a small change in temperature can significantly change the pressure in a closed system.
Stabilization time
Immediately after pressurizing the network, a natural fluctuation may occur until the temperature stabilizes.
Installation volume
The same leak size can cause a different rate of pressure drop depending on the total volume.
Instrument accuracy
A small change near the accuracy limit of the instrument should not be interpreted without additional confirmation.
Correct evaluation
Pressure, temperature, and time are recorded and, if in doubt, the test is repeated with appropriate equipment.
