The VTech MasSpec is an automatic helium leak tester capable of detecting leaks in the range of 5 x 10-6 mbar l/s, equivalent to approx. 0.1 oz. of refrigerant per year, in coils, components or refrigeration systems.

It involves pulling a deep vacuum inside the unit under test (UUT) and introducing low-pressure helium in the surrounding enclosure. Any resulting helium leakage inside the UUT is detected by the attached mass spectrometer. The test result is Pass/Fail. In order to locate the leaking point, a manual sniffer leak detector must be used.