Refrigerants & Environmental Regulations Flashcards

What refrigerant classification is R-717 (ammonia)?

Answer: B2L (higher toxicity, lower flammability)

Ammonia (R-717) is classified as B2L under ASHRAE 34 — 'B' for higher toxicity and '2L' for lower flammability (mildly flammable), requiring special safety considerations in system design and operation.

What is the primary environmental concern with R-410A that is driving its phase-down under the Kigali Amendment?

Answer: Very high global warming potential (GWP ~2088)

R-410A has a GWP of approximately 2088, making it a potent greenhouse gas; the Kigali Amendment to the Montreal Protocol requires the phase-down of high-GWP HFCs including R-410A.

What low-GWP refrigerant is being widely adopted as a replacement for R-410A in residential HVAC systems?

Answer: R-32

R-32 (difluoromethane) has a GWP of 675 — significantly lower than R-410A — and is being widely adopted as a more climate-friendly replacement for residential air conditioning globally, including in Canada.

Under Canadian ODSHAR regulations, what must technicians do with recovered refrigerant that cannot be reused?

Answer: Store it in an approved container and send it to a licensed refrigerant reclaimer or destruction facility

Intentional venting of controlled refrigerants is prohibited in Canada; recovered refrigerant that cannot be reused must be sent to a licensed reclaimer or destruction facility in approved containers.

What is R-744 and what is its main advantage as a refrigerant?

Answer: It is CO2; its GWP is 1 (the baseline), making it extremely climate-friendly

R-744 is carbon dioxide (CO2), and because GWP is referenced to CO2, its GWP is exactly 1, making it one of the most climate-friendly refrigerant options available.

What does the term 'zeotropic blend' mean for refrigerants such as R-407C?

Answer: A blend of refrigerants with different boiling points that exhibit a temperature glide during phase change

Zeotropic blends are mixtures of refrigerants with different boiling points; they exhibit temperature glide — the temperature changes during evaporation and condensation at constant pressure — which must be accounted for in system design.