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LOW GWP REFRIGERANT SAFETY EXAM LATEST 2026-2027 ACTUAL
EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+|
||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
What are zeotropic and near-azeotropic refrigerants? - ANSWER-
Refrigerants like R-407C and R-422D that have two pressure
columns on a pressure/temperature chart, using dew point (vapor)
and bubble point (liquid) for calculations.
How is superheat defined in the context of refrigerants? -
ANSWER-Superheat is the temperature of the vapor above its
boiling point at a given pressure.
What is the suction pressure and vapor line temperature for R-
422D? - ANSWER-Suction Pressure: 74 psig; Vapor line Temp:
60°F.
What is subcooling in refrigerants? - ANSWER-Subcooling is the
process of cooling a liquid refrigerant below its boiling point at a
given pressure.
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What is the discharge pressure and liquid line temperature for R-
422D? - ANSWER-Discharge Pressure: 281 psig; Liquid line
Temp: 105°F.
What is the midpoint when sizing system components for blended
refrigerants? - ANSWER-The midpoint is the average temperature
of a coil (either condenser or evaporator) in a system charged
with a blended refrigerant.
How do you calculate the evaporator midpoint for a blended
refrigerant? - ANSWER-Multiply the bubble temperature by 0.40
and the dew temperature by 0.60, then add the results together.
What is the formula for calculating the evaporator midpoint using
R-422D at 84 psig? - ANSWER-Bubble point = 45°F, Dew point =
51°F; Midpoint = (45°F × 0.40) + (51°F × 0.60) = 48.6°F.
How do you calculate the condenser midpoint for a blended
refrigerant? - ANSWER-Add the dew and bubble temperatures
together, then divide by 2.
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What is the midpoint for R-407C at 196 psig? - ANSWER-Dew
point = 100°F, Bubble point = 90.8°F; Midpoint = (100 + 90.8) ÷ 2
= 95.4°F.
What does AHRI Guideline N specify for refrigerant container
colors? - ANSWER-All refrigerant containers should be light-
green/grey (RAL 7044) and existing colors should transition to this
standard by 2020.
What must be included on containers of flammable refrigerants? -
ANSWER-A red band on the top of the container.
What does a lowercase letter designation in refrigerants indicate?
- ANSWER-It indicates an isomer, which has the same formula
and molecular weight but different arrangements and properties.
What does an uppercase letter designation in refrigerants signify?
- ANSWER-It signifies that refrigerant blends are composed of the
same refrigerants but with different percentages.
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What are Hydrofluorocarbons (HFCs)? - ANSWER-Refrigerants
containing hydrogen, fluorine, and carbon that do not deplete the
ozone layer and often have high global warming potentials (GWP)
over 1,500.
What are Hydrofluoroolefins (HFOs)? - ANSWER-Chemically
similar to HFCs, HFOs have low GWP and are mildly flammable,
used in various applications like automotive air-conditioning.
What is the trend regarding HFC/HFO blends in the HVACR
industry? - ANSWER-They are becoming more common due to
their low GWP and application-specific uses.
What are hydrocarbons (HCs) in the context of refrigerants? -
ANSWER-Refrigerants containing hydrogen and carbon,
classified as highly flammable (A3 safety group) and often
referred to as natural refrigerants.
What limitations exist for the use of hydrocarbons (HCs)? -
ANSWER-Their use is limited to systems with very small charges,
typically 5.3 ounces or less.
LOW GWP REFRIGERANT SAFETY EXAM LATEST 2026-2027 ACTUAL
EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+|
||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
What are zeotropic and near-azeotropic refrigerants? - ANSWER-
Refrigerants like R-407C and R-422D that have two pressure
columns on a pressure/temperature chart, using dew point (vapor)
and bubble point (liquid) for calculations.
How is superheat defined in the context of refrigerants? -
ANSWER-Superheat is the temperature of the vapor above its
boiling point at a given pressure.
What is the suction pressure and vapor line temperature for R-
422D? - ANSWER-Suction Pressure: 74 psig; Vapor line Temp:
60°F.
What is subcooling in refrigerants? - ANSWER-Subcooling is the
process of cooling a liquid refrigerant below its boiling point at a
given pressure.
,2|Page
What is the discharge pressure and liquid line temperature for R-
422D? - ANSWER-Discharge Pressure: 281 psig; Liquid line
Temp: 105°F.
What is the midpoint when sizing system components for blended
refrigerants? - ANSWER-The midpoint is the average temperature
of a coil (either condenser or evaporator) in a system charged
with a blended refrigerant.
How do you calculate the evaporator midpoint for a blended
refrigerant? - ANSWER-Multiply the bubble temperature by 0.40
and the dew temperature by 0.60, then add the results together.
What is the formula for calculating the evaporator midpoint using
R-422D at 84 psig? - ANSWER-Bubble point = 45°F, Dew point =
51°F; Midpoint = (45°F × 0.40) + (51°F × 0.60) = 48.6°F.
How do you calculate the condenser midpoint for a blended
refrigerant? - ANSWER-Add the dew and bubble temperatures
together, then divide by 2.
,3|Page
What is the midpoint for R-407C at 196 psig? - ANSWER-Dew
point = 100°F, Bubble point = 90.8°F; Midpoint = (100 + 90.8) ÷ 2
= 95.4°F.
What does AHRI Guideline N specify for refrigerant container
colors? - ANSWER-All refrigerant containers should be light-
green/grey (RAL 7044) and existing colors should transition to this
standard by 2020.
What must be included on containers of flammable refrigerants? -
ANSWER-A red band on the top of the container.
What does a lowercase letter designation in refrigerants indicate?
- ANSWER-It indicates an isomer, which has the same formula
and molecular weight but different arrangements and properties.
What does an uppercase letter designation in refrigerants signify?
- ANSWER-It signifies that refrigerant blends are composed of the
same refrigerants but with different percentages.
, 4|Page
What are Hydrofluorocarbons (HFCs)? - ANSWER-Refrigerants
containing hydrogen, fluorine, and carbon that do not deplete the
ozone layer and often have high global warming potentials (GWP)
over 1,500.
What are Hydrofluoroolefins (HFOs)? - ANSWER-Chemically
similar to HFCs, HFOs have low GWP and are mildly flammable,
used in various applications like automotive air-conditioning.
What is the trend regarding HFC/HFO blends in the HVACR
industry? - ANSWER-They are becoming more common due to
their low GWP and application-specific uses.
What are hydrocarbons (HCs) in the context of refrigerants? -
ANSWER-Refrigerants containing hydrogen and carbon,
classified as highly flammable (A3 safety group) and often
referred to as natural refrigerants.
What limitations exist for the use of hydrocarbons (HCs)? -
ANSWER-Their use is limited to systems with very small charges,
typically 5.3 ounces or less.
