EPA SECTION 608 EXAM | QUESTIONS AND ANSWERS | VERIED
ANSWERS | ALREADY GRADED A+ | LATEST EXAM
Compressor crankcase heaters (CCH) are used in refrigeration and air
conditioning to reduce what?
Reduce the amount of refrigerant in the oil
Compressor
Refrigerant system component that changes a low-pressure, low-temperature,
superheated vapor upon entry, to a high-pressure, high-temperature, highly
superheated vapor upon exit.
Compressors can only compress a gas
Condenser
The refrigerant system component where the refrigerant enters as a high-
pressure, high temperature vapor, circulates through a series of coils, and exits
as a high pressure, subcooled liquid
Receiver
The component in a refrigeration system directly following the condenser in a
refrigeration system using a thermal expansion valve
Where is the liquid receiver located in a system that uses a thermostatic
expansion valve?
Liquid line directly after the condenser
The state of refrigerant leaving the evaporator is?
Low pressure, low temperature superheated vapor
Refrigerant Migration
Refrigerant, traveling to the compressors suction line, or crankcase, during the
off cycle
Oil Sample Reason #1
A reason to take an oil sample is a unit that has had a compressor burnout
Oil Sample Reason #2
,An oil sample should be taken when a unit has had a leak or a major component
failure, as well as when moisture, acid, oil sludge formation, oil waxing, or
residual acidic oil from a burnout are suspected. A suspected increase in
temperature glide is not a reason to take an oil sample
500 Microns
After making a major repair, the appliance should be dehydrated by evacuating
the system to a minimum of 500 microns. This is also the minimum evacuation
level that should be achieved in most refrigeration systems before charging the
system.
Why should you never operate a compressor when the system is in deep
vacuum?
internal electrical arching could occur and burn the motor windings
Gauge Manifold Set
The color of the low pressure gauge on a typical gauge manifold set is blue.
The color of the high-pressure gauge on a typical gauge manifold set is red
Inches Hg and Psig
The compound pressure gauge for the low side of the system measures pressure
in Psig and inches of mercury
Low loss fittings
Recovery devices used to recover CFCs, HCFCs, and HFCs should contain low
loss fittings that can be either manually closed or automatically closed when
disconnected to prevent loss of refrigerant from hoses.
Ozone
The ozone layer protects the earth from ultraviolet radiation from the sun.
Ozone is the stratosphere above the earth consists of molecules containing three
(3) oxygen atoms. Depletion of ozone in the stratosphere is a global problem,
ODP
Ozone Depletion Potential. The ability of a substance to destroy ozone in the
stratosphere. CFCs have the highest ODP
Stratospheric Ozone
Helps form the earths protective shield. CFC and HCFC refrigerants damage the
stratospheric ozone. Miles 7 to 30 from earths surface
,Chlorine
The element of a CFC of HCFC molecule that causes ozone depletion. The
chlorine in CFCs and HCFCs will not dissolve in water or easily break down in
the atmosphere. Each chlorine atom in the stratosphere can destroy 100,000
ozone molecules
CFC
Chlorofluorocarbon. CFC refrigerants are the most harmful to stratospheric
ozone and have the highest ozone depletion potential (ODP).
CFCs do not dissolve in water so cannot be rained out out of the atmosphere.
Examples of CFC refrigerants include R-12
The ability of a substance to destroy ozone in the stratosphere is measured
by its?
ODP
Each chlorine atom in the stratosphere can destroy up to how many ozone
molecules?
100,000
Which of the following is not a component of CFC?
Hydrogen
HCFCs contain...
Hydrogen, Chlorine, Fluorine, and Carbon
GWP
Global Warming Potential. Provides a comparison of global warming impacts of
different gases over a span of time. R-600a (an HC) has a low GWP, while the
GWP of R-410a compared to carbon dioxide is thousands of time greater.
CO2 (R-744)
Carbon Dioxide. Used as the baseline measurement for global warming
potential (GWP)
HFO
Hydrofluoroolefin. An A2L refrigerant class with non-ozone depleting and low
global warming potential characteristics.
HFOs typically have the lowest global warming potential (GWP)
HFO refrigerants are less flammable than hydrocarbon refrigerants because they
, contain fluorine but are still mildly flammable. An example of an HFO
refrigerant is R-1234yf
Which refrigerant is used as the baseline for measuring global warming
potential?
R-744
A1
ASHRAE refrigerant safety classification. An A1 designation is considered the
safest
A2L
ASHRAE refrigerant safety classification. An A2L indicates lower flammability
A3
An A3 classification indicates a higher flammability refrigerant
HCFC
Hydrochlorofluorocarbon. HCFC refrigerants contain hydrogen, chlorine,
fluorine, and carbon
Azeotropic Refrigerant Mixture
An azeotropic refrigerant mixture is unique in the fact that the mixture acts like
a single component refrigerant over its entire range
Ternary Blend
A three-part mixture refrigerant
Which is the higher flammability rating?
A3
Which of the following has the highest ozone depletion potential?
CFC
Which ASHRAE classification means slightly flammable?
A2L
Temperature Glide
The term used to describe the fact that a refrigerant blend has a range of bubble
or dew points at a constant pressure
ANSWERS | ALREADY GRADED A+ | LATEST EXAM
Compressor crankcase heaters (CCH) are used in refrigeration and air
conditioning to reduce what?
Reduce the amount of refrigerant in the oil
Compressor
Refrigerant system component that changes a low-pressure, low-temperature,
superheated vapor upon entry, to a high-pressure, high-temperature, highly
superheated vapor upon exit.
Compressors can only compress a gas
Condenser
The refrigerant system component where the refrigerant enters as a high-
pressure, high temperature vapor, circulates through a series of coils, and exits
as a high pressure, subcooled liquid
Receiver
The component in a refrigeration system directly following the condenser in a
refrigeration system using a thermal expansion valve
Where is the liquid receiver located in a system that uses a thermostatic
expansion valve?
Liquid line directly after the condenser
The state of refrigerant leaving the evaporator is?
Low pressure, low temperature superheated vapor
Refrigerant Migration
Refrigerant, traveling to the compressors suction line, or crankcase, during the
off cycle
Oil Sample Reason #1
A reason to take an oil sample is a unit that has had a compressor burnout
Oil Sample Reason #2
,An oil sample should be taken when a unit has had a leak or a major component
failure, as well as when moisture, acid, oil sludge formation, oil waxing, or
residual acidic oil from a burnout are suspected. A suspected increase in
temperature glide is not a reason to take an oil sample
500 Microns
After making a major repair, the appliance should be dehydrated by evacuating
the system to a minimum of 500 microns. This is also the minimum evacuation
level that should be achieved in most refrigeration systems before charging the
system.
Why should you never operate a compressor when the system is in deep
vacuum?
internal electrical arching could occur and burn the motor windings
Gauge Manifold Set
The color of the low pressure gauge on a typical gauge manifold set is blue.
The color of the high-pressure gauge on a typical gauge manifold set is red
Inches Hg and Psig
The compound pressure gauge for the low side of the system measures pressure
in Psig and inches of mercury
Low loss fittings
Recovery devices used to recover CFCs, HCFCs, and HFCs should contain low
loss fittings that can be either manually closed or automatically closed when
disconnected to prevent loss of refrigerant from hoses.
Ozone
The ozone layer protects the earth from ultraviolet radiation from the sun.
Ozone is the stratosphere above the earth consists of molecules containing three
(3) oxygen atoms. Depletion of ozone in the stratosphere is a global problem,
ODP
Ozone Depletion Potential. The ability of a substance to destroy ozone in the
stratosphere. CFCs have the highest ODP
Stratospheric Ozone
Helps form the earths protective shield. CFC and HCFC refrigerants damage the
stratospheric ozone. Miles 7 to 30 from earths surface
,Chlorine
The element of a CFC of HCFC molecule that causes ozone depletion. The
chlorine in CFCs and HCFCs will not dissolve in water or easily break down in
the atmosphere. Each chlorine atom in the stratosphere can destroy 100,000
ozone molecules
CFC
Chlorofluorocarbon. CFC refrigerants are the most harmful to stratospheric
ozone and have the highest ozone depletion potential (ODP).
CFCs do not dissolve in water so cannot be rained out out of the atmosphere.
Examples of CFC refrigerants include R-12
The ability of a substance to destroy ozone in the stratosphere is measured
by its?
ODP
Each chlorine atom in the stratosphere can destroy up to how many ozone
molecules?
100,000
Which of the following is not a component of CFC?
Hydrogen
HCFCs contain...
Hydrogen, Chlorine, Fluorine, and Carbon
GWP
Global Warming Potential. Provides a comparison of global warming impacts of
different gases over a span of time. R-600a (an HC) has a low GWP, while the
GWP of R-410a compared to carbon dioxide is thousands of time greater.
CO2 (R-744)
Carbon Dioxide. Used as the baseline measurement for global warming
potential (GWP)
HFO
Hydrofluoroolefin. An A2L refrigerant class with non-ozone depleting and low
global warming potential characteristics.
HFOs typically have the lowest global warming potential (GWP)
HFO refrigerants are less flammable than hydrocarbon refrigerants because they
, contain fluorine but are still mildly flammable. An example of an HFO
refrigerant is R-1234yf
Which refrigerant is used as the baseline for measuring global warming
potential?
R-744
A1
ASHRAE refrigerant safety classification. An A1 designation is considered the
safest
A2L
ASHRAE refrigerant safety classification. An A2L indicates lower flammability
A3
An A3 classification indicates a higher flammability refrigerant
HCFC
Hydrochlorofluorocarbon. HCFC refrigerants contain hydrogen, chlorine,
fluorine, and carbon
Azeotropic Refrigerant Mixture
An azeotropic refrigerant mixture is unique in the fact that the mixture acts like
a single component refrigerant over its entire range
Ternary Blend
A three-part mixture refrigerant
Which is the higher flammability rating?
A3
Which of the following has the highest ozone depletion potential?
CFC
Which ASHRAE classification means slightly flammable?
A2L
Temperature Glide
The term used to describe the fact that a refrigerant blend has a range of bubble
or dew points at a constant pressure
