A2L STANDARD EXAMS ALL ANSWERS AND
QUESTIONS SET A+
✔✔When a vapor is superheated, it means that ___________ heat has been added
after it has changed state. - ✔✔sensible
✔✔Adding ___________ heat to a substance will cause it to change state. - ✔✔latent
✔✔Vapor line temperature - Low side saturation temperature = ___________ -
✔✔super heat
✔✔High side saturation temperature - Liquid line temperature = ___________ -
✔✔subcooling
✔✔In air conditioning applications, the industry standard for airflow across the
evaporator is ___________ cubic feet per minute (CFM), per ton of cooling. - ✔✔400
✔✔Refrigerant blends are created in the factory by ___________ and ___________,
not in the field by technicians. - ✔✔chemist, engineers
✔✔An ___________ refrigerant blend behaves like a single compound refrigerant. -
✔✔azeotropic
✔✔A ___________ refrigerant blend is a mixture of two or more refrigerants that can
separate, or fractionate, into its original components. - ✔✔zeotropic
✔✔___________ occurs when one or more of the refrigerants in a blend leaks at a
faster rate than other refrigerants in the blend. - ✔✔fractionation
✔✔___________ is term used to describe the range of boiling (or condensing)
temperatures for a refrigerant at a given pressure. - ✔✔temperature glide
, ✔✔When working with zeotropic and near-azeotropic refrigerants, the ___________ is
used for calculating superheat. - ✔✔dew point (vapor phase)
✔✔When working with zeotropic and near-azeotropic refrigerants, the ___________ is
used for calculating subcooling. - ✔✔bubble point (liquid phase)
✔✔When sizing and selecting system components for equipment that is charged with a
zeotropic or near-azeotropic refrigerant blend, the ___________ should be used. -
✔✔midpoint
✔✔AHRI Guideline N, Assignment of Refrigerant Container Colors, specifies that all
refrigerant containers should have one uniform paint color, a ___________ - ✔✔light-
green/grey
✔✔Flammable refrigerant tanks must continue to include a ___________ on the top of
the container. - ✔✔red band
✔✔Refrigerants that have a lowercase letter (a.b.c) designation indicate an
___________ - ✔✔isomer
✔✔An ___________ designation is used when the refrigerant blends are composed of
the same refrigerants, but with different percentages of each. - ✔✔uppercase letter
(A,B,C)
✔✔___________ contain hydrogen, flourine, and carbon and do not deplete the ozone
as they have no chlorine, and most have a high GWP. - ✔✔Hydrofluorocarbons (HFCs)
✔✔___________ refrigerants have a very low, single digit, global warming potential and
most are midly flammable (A2L) - ✔✔Hydrofluoroolefins (HFOs)
✔✔___________ refrigerants contain hydrogen and carbon and are classified by
ASHRAE in the A3 safety group, which are high flammable, and are often referred to as
natural referants. - ✔✔Hydrocarbons (HCs)
✔✔All refrigerant oils are ___________, meaning that they absorb moisture. -
✔✔hygroscopic
✔✔___________ oil is a synthetic oil suitable for most refrigeration systems using HFC
and HFO refrigerants, is very hygroscopic, and should not be exposed to the
atmosphere. - ✔✔Polyol Ester
QUESTIONS SET A+
✔✔When a vapor is superheated, it means that ___________ heat has been added
after it has changed state. - ✔✔sensible
✔✔Adding ___________ heat to a substance will cause it to change state. - ✔✔latent
✔✔Vapor line temperature - Low side saturation temperature = ___________ -
✔✔super heat
✔✔High side saturation temperature - Liquid line temperature = ___________ -
✔✔subcooling
✔✔In air conditioning applications, the industry standard for airflow across the
evaporator is ___________ cubic feet per minute (CFM), per ton of cooling. - ✔✔400
✔✔Refrigerant blends are created in the factory by ___________ and ___________,
not in the field by technicians. - ✔✔chemist, engineers
✔✔An ___________ refrigerant blend behaves like a single compound refrigerant. -
✔✔azeotropic
✔✔A ___________ refrigerant blend is a mixture of two or more refrigerants that can
separate, or fractionate, into its original components. - ✔✔zeotropic
✔✔___________ occurs when one or more of the refrigerants in a blend leaks at a
faster rate than other refrigerants in the blend. - ✔✔fractionation
✔✔___________ is term used to describe the range of boiling (or condensing)
temperatures for a refrigerant at a given pressure. - ✔✔temperature glide
, ✔✔When working with zeotropic and near-azeotropic refrigerants, the ___________ is
used for calculating superheat. - ✔✔dew point (vapor phase)
✔✔When working with zeotropic and near-azeotropic refrigerants, the ___________ is
used for calculating subcooling. - ✔✔bubble point (liquid phase)
✔✔When sizing and selecting system components for equipment that is charged with a
zeotropic or near-azeotropic refrigerant blend, the ___________ should be used. -
✔✔midpoint
✔✔AHRI Guideline N, Assignment of Refrigerant Container Colors, specifies that all
refrigerant containers should have one uniform paint color, a ___________ - ✔✔light-
green/grey
✔✔Flammable refrigerant tanks must continue to include a ___________ on the top of
the container. - ✔✔red band
✔✔Refrigerants that have a lowercase letter (a.b.c) designation indicate an
___________ - ✔✔isomer
✔✔An ___________ designation is used when the refrigerant blends are composed of
the same refrigerants, but with different percentages of each. - ✔✔uppercase letter
(A,B,C)
✔✔___________ contain hydrogen, flourine, and carbon and do not deplete the ozone
as they have no chlorine, and most have a high GWP. - ✔✔Hydrofluorocarbons (HFCs)
✔✔___________ refrigerants have a very low, single digit, global warming potential and
most are midly flammable (A2L) - ✔✔Hydrofluoroolefins (HFOs)
✔✔___________ refrigerants contain hydrogen and carbon and are classified by
ASHRAE in the A3 safety group, which are high flammable, and are often referred to as
natural referants. - ✔✔Hydrocarbons (HCs)
✔✔All refrigerant oils are ___________, meaning that they absorb moisture. -
✔✔hygroscopic
✔✔___________ oil is a synthetic oil suitable for most refrigeration systems using HFC
and HFO refrigerants, is very hygroscopic, and should not be exposed to the
atmosphere. - ✔✔Polyol Ester
