Which statement describes a characteristic associated with a zeotropic blend?

• A. Two saturation valves that are far apart
• B. Access fittings
• C. Defrost heaters
• D. Release trapped refrigerant from the compressor oil

Answer: (A)

Zeotropic blends show a temperature glide during phase change because their components boil at different temperatures. As the refrigerant evaporates, the composition of the liquid and vapor changes, so there isn’t a single, sharp saturation temperature. Instead, evaporation occurs over a band of temperatures, meaning the two saturation conditions can be noticeably separated. Saying there are two saturation points that are far apart captures this wide boiling range inherent to a zeotropic mixture.

In contrast, the other options refer to hardware or procedures rather than a fundamental property of the blend, so they don’t describe what characteristic defines a zeotropic refrigerant.