Practice Test Geeks(A2L) A2L Low GWP Flammable Refrigerant Safety Certification Practice Test
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Properties and Classification Flashcards

6 cards from real A2L practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 Properties and Classification flashcards as text

  1. R-454B is a blend of which two refrigerants?

    Answer: R-32 and R-1234yf

    R-454B consists of 68.9% R-32 and 31.1% R-1234yf by weight. This blend achieves a balance of performance, lower GWP (466), and A2L safety classification.

  2. What is 'temperature glide' in an A2L refrigerant blend?

    Answer: The difference between the dew point and bubble point temperatures at a given pressure — the blend evaporates and condenses over a temperature range rather than at a single temperature

    Temperature glide occurs in blends where different components evaporate at different rates. R-454B has a small glide (~1.5°C), while some blends have larger glides affecting system design.

  3. How does the operating pressure of R-32 compare to R-410A?

    Answer: Slightly higher than R-410A

    R-32 operates at slightly higher pressures than R-410A. This means R-410A components may not be directly reusable, and technicians need to verify equipment pressure ratings.

  4. What property makes A2L refrigerants more environmentally friendly than traditional HFCs?

    Answer: Their significantly lower Global Warming Potential means less impact on climate change if released to the atmosphere

    The primary environmental advantage is dramatically lower GWP. While all HFCs contribute to global warming if released, A2L alternatives contribute far less per kilogram than R-410A.

  5. What is 'fractionation' and why is it a concern with A2L refrigerant blends?

    Answer: When blend components separate due to different leak rates, changing the remaining refrigerant's composition and properties

    In blends like R-454B, different components have different vapor pressures. During a leak, the more volatile component escapes faster, leaving a blend with altered composition, changed performance, and potentially different safety characteristics.

  6. Which A2L refrigerant has the lowest GWP and is primarily used in automotive air conditioning?

    Answer: R-1234yf

    R-1234yf (HFO-1234yf) has a GWP of less than 1 — essentially no global warming impact. It's the global standard replacement for R-134a in automotive AC systems.