A low-side gauge on an R-22 system reads 0 psig. What is the absolute pressure at sea level?
Refrigeration · EPA 608 Type II. The correct answer, and the reasoning behind it.
Identifying refrigerants, system components and the state of refrigerant in each.
The question
A low-side gauge on an R-22 system reads 0 psig. What is the absolute pressure at sea level?
- 0 psia
- 14.7 psiaCorrect answer
- 29.9 psia
- -14.7 psia
Why “14.7 psia” is correct
A gauge reads 0 at atmospheric pressure, which is about 14.7 psia at sea level. To convert any gauge reading to absolute pressure, add 14.7.
Source: EPA: Test Topics
Why the other answers are wrong
- 0 psia — 0 psia would be a perfect vacuum.
- 29.9 psia — 29.9 is atmospheric pressure in inches of mercury, not psi.
- -14.7 psia — Absolute pressure cannot be negative.
Practice more of this
More EPA 608 Type II 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.