Refrigerant Properties and Identification Flashcards

What is the ASHRAE/ARI standard cylinder color for R-22 refrigerant?

Answer: Green

ASHRAE/ARI assigns green as the standard cylinder color for R-22 to prevent misidentification during service.

Which refrigerant is classified as a hydrofluorocarbon (HFC)?

Answer: R-134a

R-134a is an HFC (tetrafluoroethane) containing only hydrogen, fluorine, and carbon — no chlorine — giving it zero ozone depletion potential.

What does the term 'azeotropic blend' mean when referring to refrigerants?

Answer: A mixture that behaves like a single refrigerant with a constant boiling point

An azeotropic blend maintains its composition during phase changes and boils at a constant temperature, behaving like a single-component refrigerant.

Which of the following is a chlorofluorocarbon (CFC) refrigerant?

Answer: R-12

R-12 (dichlorodifluoromethane) is a CFC containing only chlorine and fluorine with no hydrogen, making it highly ozone-depleting and fully phased out.

What substance serves as the reference standard (GWP = 1) for Global Warming Potential calculations?

Answer: Carbon dioxide (CO2)

CO2 has a defined GWP of 1 and serves as the baseline against which all other greenhouse gases are measured over a 100-year horizon.

Which refrigerant blend is classified as zeotropic (near-azeotropic)?

Answer: R-407C

R-407C is a zeotropic HFC blend of R-32, R-125, and R-134a that exhibits temperature glide because its components have different boiling points.

What ozone depletion potential (ODP) does R-134a have?

Answer: 0

R-134a has an ODP of zero because it contains no chlorine or bromine atoms — the elements responsible for destroying stratospheric ozone.