Leak testing a low-pressure refrigeration system with nitrogen in excess of 10 psig could cause which component to fail?

• A. ruptured disc
• B. relief valve
• C. gauge
• D. valve seat

Answer: (A)

When you test for leaks by pressurizing with gas, safety devices are the first line of protection against overpressure. A ruptured disc is a one‑time, sacrificial safety component that is designed to burst open if the pressure reaches its predetermined limit. If you push nitrogen into a low‑pressure refrigeration system above that limit, the disc will rupture to relieve the excess pressure, protecting the rest of the system from more serious damage. The relief valve is intended to vent only at its own set point, which is usually higher than the disc’s burst pressure, so it isn’t expected to fail in this lower‑pressure leak test. The gauge and valve seats are not the devices designed to fail under an overpressure event in this context; the ruptured disc is the component that’s meant to give way.