At standard atmospheric pressure, R-123 boils at about what temperature?
Refrigeration · EPA 608 Type III. The correct answer, and the reasoning behind it.
Purge units and pressure-temperature behaviour of low-pressure refrigerants.
The question
At standard atmospheric pressure, R-123 boils at about what temperature?
- -41 °F
- 82 °FCorrect answer
- -15 °F
- 118 °F
Why “82 °F” is correct
R-123 boils near 82 °F (27.8 °C) at 29.9 inches of mercury, and R-11 near 75 °F (23.8 °C). Because those boiling points sit close to room temperature, R-123 and R-11 chillers sit near atmospheric pressure when idle and run in a vacuum in the evaporator.
Source: EPA: Test Topics; Hudson Technologies R-123 and R-11 P-T charts
Why the other answers are wrong
- -41 °F — -41 °F is the boiling point of R-22, a much higher-pressure refrigerant.
- -15 °F — -15 °F is close to the boiling point of R-134a.
- 118 °F — 118 °F is close to the boiling point of R-113.
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.