What is the highest pressure normally used when leak testing a low-pressure centrifugal chiller?
Leak detection · EPA 608 Type III. The correct answer, and the reasoning behind it.
Pressurizing low-pressure systems for leak tests, signs of leaks, inspections and reports.
The question
What is the highest pressure normally used when leak testing a low-pressure centrifugal chiller?
- 0 psig
- 15 psig
- 10 psigCorrect answer
- 30 psig
Why “10 psig” is correct
EPA's test topics ask for the maximum leak test pressure without giving a number, and trade training teaches 10 psig. Low-pressure chiller shells are protected by a rupture disc, which on Trane CenTraVac chillers breaks at 15 psig, so staying at or under 10 psig keeps a margin below it. Some manufacturers set a lower limit (Trane specifies 8 psig of dry nitrogen), and the unit's own manual governs.
Source: EPA: Test Topics; Trane CVHE-SVX005E-EN, CenTraVac IOM (15 psig rupture disk); Trane CTV-SVX05H-EN, R-123 handling guide (8 psig leak test)
Why the other answers are wrong
- 0 psig — 0 psig is atmospheric pressure, which is not enough to push refrigerant out through a leak.
- 15 psig — 15 psig is a common rupture disc setting, so testing there risks bursting the disc.
- 30 psig — 30 psig is well beyond what a low-pressure chiller shell is protected for.
Practice more of this
More EPA 608 Type III practice questions, or see every EPA 608 practice test.
Unofficial, not affiliated with the EPA or any EPA-approved certifying organization. Questions are original practice written from public EPA material, not real exam questions.