EPA 608 609 Refrigerant Properties and Identification 2 — Questions and Answers
Question 1: What is the ASHRAE/ARI standard cylinder color for R-410A refrigerant?
- Green
- Orange
- Rose (pink) (Correct answer)
- Yellow
Correct answer: Rose (pink)
ASHRAE/ARI assigns rose (pink) as the standard cylinder color for R-410A to distinguish it from other refrigerants during service.
Question 2: Which refrigerant is classified as an HCFC (hydrochlorofluorocarbon)?
- R-12
- R-410A
- R-22 (Correct answer)
- R-134a
Correct answer: R-22
R-22 is an HCFC (chlorodifluoromethane) because it contains hydrogen, chlorine, and fluorine; its chlorine content gives it an ODP of 0.055.
Question 3: What does a refrigerant's 'critical temperature' refer to?
- The temperature at which it becomes flammable
- The lowest temperature achievable in the refrigeration cycle
- The temperature above which it cannot be liquefied regardless of pressure (Correct answer)
- The boiling point at atmospheric pressure
Correct answer: The temperature above which it cannot be liquefied regardless of pressure
The critical temperature is the point above which a refrigerant exists only as a gas and cannot be liquefied by increasing pressure, defining the upper bound of the two-phase region.
Question 4: Which of the following refrigerants has the highest ozone depletion potential (ODP)?
- R-22
- R-12 (Correct answer)
- R-134a
- R-410A
Correct answer: R-12
R-12, a CFC, has an ODP of 1.0 — the reference value — which is higher than R-22's ODP of 0.055; HFCs like R-134a and R-410A have zero ODP.
Question 5: What ASHRAE/ARI color code identifies R-404A refrigerant cylinders?
- Green
- Rose (pink)
- Orange (Correct answer)
- Light blue
Correct answer: Orange
ASHRAE/ARI assigns orange as the standard cylinder color for R-404A, the HFC blend widely used in commercial refrigeration as an R-502 replacement.
Question 6: Which ASHRAE refrigerant numbering series designates inorganic compounds such as ammonia and CO2?
- 100 series
- 400 series
- 600 series
- 700 series (Correct answer)
Correct answer: 700 series
The 700 series designates inorganic refrigerants in the ASHRAE 34 system, including R-717 (ammonia) and R-744 (carbon dioxide).
Question 7: What is the approximate normal boiling point of R-134a at atmospheric pressure?
- -41°F (-41°C)
- -15°F (-26°C) (Correct answer)
- 5°F (-15°C)
- -62°F (-52°C)
Correct answer: -15°F (-26°C)
R-134a boils at approximately -15°F (-26.1°C) at atmospheric pressure, which is higher than older CFC and HCFC refrigerants like R-12 and R-22.
EPA 608 609 Refrigerant Properties and Identification 2
What is the ASHRAE/ARI standard cylinder color for R-410A refrigerant?