Refrigerant Identification & Testing Flashcards
7 cards from real CFC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Refrigerant Identification & Testing flashcards as text
What does the term 'temperature glide' mean when referring to zeotropic refrigerant blends?
Answer: The difference in temperature between the start and end of evaporation or condensation at constant pressure
Temperature glide is the range between the bubble point and dew point temperatures of a zeotropic blend at constant pressure, meaning the blend changes phase over a temperature range rather than at a single point.
Which refrigerant has the highest Ozone Depletion Potential (ODP) among the following options?
Answer: R-11
R-11 (trichlorofluoromethane) has an ODP of 1.0, which is the Montreal Protocol reference value, compared to R-22's ODP of 0.05, while R-134a and R-410A have an ODP of zero.
What is the significance of a refrigerant's Global Warming Potential (GWP) value?
Answer: It compares the refrigerant's heat-trapping ability to CO2 over a 100-year period
GWP quantifies how much heat a refrigerant traps in the atmosphere relative to CO2 (GWP = 1) over 100 years, helping regulators assess climate impact during refrigerant leaks.
What is the correct method for sampling vapor-phase refrigerant from a cylinder when using a refrigerant identifier?
Answer: Sample from the vapor phase after allowing the cylinder to stabilize at room temperature
Vapor-phase samples taken after the cylinder has thermally stabilized at room temperature provide the most accurate and representative composition reading for refrigerant identification.
How does a technician confirm that a system has been adequately evacuated of refrigerant before opening it for component replacement?
Answer: Measure system pressure with manifold gauges — readings should be at or below atmospheric (0 psig or in vacuum)
After refrigerant recovery, manifold gauges must show pressure at or below atmospheric (ideally in vacuum) to confirm the system is safe to open for repairs without releasing refrigerant.
What contaminant is most likely present when recovered refrigerant from a system has a sharp, pungent, acrid odor?
Answer: Acid and decomposition products from a compressor motor burnout
A pungent or acrid odor in recovered refrigerant indicates acidic decomposition products from a motor burnout, where extreme heat has broken down refrigerant and oil into corrosive compounds.
Which regulatory framework governs the labeling, marking, and transportation requirements for refrigerant cylinders shipped in the United States?
Answer: DOT Hazardous Materials Regulations under 49 CFR
The U.S. Department of Transportation regulates refrigerant cylinders under 49 CFR as hazardous materials, covering proper labeling, marking, placarding, and shipping requirements.