EPA 608 UNIVERSAL EXAM 2024-2025 ACTUAL EXAM
ALL 250 QUESTIONS AND CORRECT DETAILED
ANSWERWERS WITH RATIONALES (VERIFIED
ANSWERWERS) |ALREADY GRADED A+
Where does refrigerant go after it leaves the purge unit of a low-pressure centrifugal system? -
ANSWERWER-The evaporator
Which refrigerants can be mixed in an appliance? - ANSWERWER-Refrigerants cannot be mixed
What gas should be used to leak check a system designed for use with R-410A that has been opened for
a major system repair? - ANSWERWER-Pressurized nitrogen
What is the term for removing refrigerant in any condition from a system and storing it in an external
container without necessarily testing or processing it in any way? - ANSWERWER-Recovery
What is meant by the term "high efficiency purge unit"? - ANSWERWER-Purge units that discharge a low
percentage of refrigerant with the air they remove
Before beginning a refrigerant recovery procedure, it is ALWAYS necessary to: - ANSWERWER-know the
type of refrigerant in the system
Which of the following gases is used as the baseline measurement for global warming potential? -
ANSWERWER-Carbon Dioxide
Which hydrocarbon refrigerant is approved for retrofit into existing household refrigerators? -
ANSWERWERHC R-600a 2 ounces or less
Recovered refrigerant may contain which of the following impurities? - ANSWERWER-Acids, moisture,
and oil
,A hydrostatic tube test kit will - ANSWERWER-determine if a lube leaks
When installing any type of access fitting onto a sealed system: - ANSWERWER-the fitting should be leak
tested before proceeding with recovery
A chiller with a charge of 200 pounds of an ozone-depleting refrigerant has passed the initial verification
leak test. When must a follow-up verification test be conducted? - ANSWERWER-Within 10 days
Why are some hydrofluoroolefin (HFO) refrigerants classified as "A2L"? - ANSWERWER-They are less
flammable than hydrocarbon refrigerants, but most are still mildly flammable
To determine if the system is leaking more than the allowed rate, the EPA allows the use of which one of
the following methods to determine the full charge? - ANSWERWER-Use of calculations based on
component and pipe sizes
When could a reciprocating compressor be damaged if energized? - ANSWERWER-When the discharge
service valve is closed
Which of the following are included in EPA's definition of a "small appliance"? - ANSWERWER-Products
manufactured, fully charged and hermetically sealed in a factory
Recovering refrigerant from a system in the vapor phase will minimize the loss of which of the following?
- ANSWERWER-Oil
Which of the following is an indicator of a leak in a high-pressure system with a capillary tube? -
ANSWERWER-Excessive superheat
A typical setting for the high-pressure cut-out control on a recovery unit used for evacuating the
refrigerant from a low-pressure chiller is: - ANSWERWER-10 psig
When is it essential to take measures to help release trapped CFC, HCFC, or HFC refrigerant from the
compressor oil during refrigerant recovery? - ANSWERWER-When using self-contained recovery devices
, Excessive running of a purge system on a low-pressure chiller generally indicates what condition? -
ANSWERWER-Leaking system
Which of the following always falls under the EPA definition for "major maintenance, service, or repair"?
- ANSWERWER-Replacing a compressor
What effect will low ambient temperatures have on recovery? - ANSWERWER-Increase the recovery
time
What should be used to remove ice from sight glasses or viewing glasses? - ANSWERWER-An alcohol
spray
After installation of a field piped split system, the unit should first be pressurized with: -
ANSWERWERnitrogen and leak checked
Pressure relief valves can only be installed: - ANSWERWER-in parallel
How many access valves are needed to recover the refrigerant on a sealed system with an operating
compressor that has a completely restricted capillary tube? - ANSWERWER-Only one access valve, on
the high side of the system
What is the state of the refrigerant entering the compressor of a refrigerant system? - ANSWERWER-
Low pressure vapor
When first inspecting a hermetic system known to be leaking, you should look for: - ANSWERWER-
traces of oil
Why should low and high side access valves be installed when recovering refrigerant from a household
refrigerator? - ANSWERWER-To improve speed of recovery
ALL 250 QUESTIONS AND CORRECT DETAILED
ANSWERWERS WITH RATIONALES (VERIFIED
ANSWERWERS) |ALREADY GRADED A+
Where does refrigerant go after it leaves the purge unit of a low-pressure centrifugal system? -
ANSWERWER-The evaporator
Which refrigerants can be mixed in an appliance? - ANSWERWER-Refrigerants cannot be mixed
What gas should be used to leak check a system designed for use with R-410A that has been opened for
a major system repair? - ANSWERWER-Pressurized nitrogen
What is the term for removing refrigerant in any condition from a system and storing it in an external
container without necessarily testing or processing it in any way? - ANSWERWER-Recovery
What is meant by the term "high efficiency purge unit"? - ANSWERWER-Purge units that discharge a low
percentage of refrigerant with the air they remove
Before beginning a refrigerant recovery procedure, it is ALWAYS necessary to: - ANSWERWER-know the
type of refrigerant in the system
Which of the following gases is used as the baseline measurement for global warming potential? -
ANSWERWER-Carbon Dioxide
Which hydrocarbon refrigerant is approved for retrofit into existing household refrigerators? -
ANSWERWERHC R-600a 2 ounces or less
Recovered refrigerant may contain which of the following impurities? - ANSWERWER-Acids, moisture,
and oil
,A hydrostatic tube test kit will - ANSWERWER-determine if a lube leaks
When installing any type of access fitting onto a sealed system: - ANSWERWER-the fitting should be leak
tested before proceeding with recovery
A chiller with a charge of 200 pounds of an ozone-depleting refrigerant has passed the initial verification
leak test. When must a follow-up verification test be conducted? - ANSWERWER-Within 10 days
Why are some hydrofluoroolefin (HFO) refrigerants classified as "A2L"? - ANSWERWER-They are less
flammable than hydrocarbon refrigerants, but most are still mildly flammable
To determine if the system is leaking more than the allowed rate, the EPA allows the use of which one of
the following methods to determine the full charge? - ANSWERWER-Use of calculations based on
component and pipe sizes
When could a reciprocating compressor be damaged if energized? - ANSWERWER-When the discharge
service valve is closed
Which of the following are included in EPA's definition of a "small appliance"? - ANSWERWER-Products
manufactured, fully charged and hermetically sealed in a factory
Recovering refrigerant from a system in the vapor phase will minimize the loss of which of the following?
- ANSWERWER-Oil
Which of the following is an indicator of a leak in a high-pressure system with a capillary tube? -
ANSWERWER-Excessive superheat
A typical setting for the high-pressure cut-out control on a recovery unit used for evacuating the
refrigerant from a low-pressure chiller is: - ANSWERWER-10 psig
When is it essential to take measures to help release trapped CFC, HCFC, or HFC refrigerant from the
compressor oil during refrigerant recovery? - ANSWERWER-When using self-contained recovery devices
, Excessive running of a purge system on a low-pressure chiller generally indicates what condition? -
ANSWERWER-Leaking system
Which of the following always falls under the EPA definition for "major maintenance, service, or repair"?
- ANSWERWER-Replacing a compressor
What effect will low ambient temperatures have on recovery? - ANSWERWER-Increase the recovery
time
What should be used to remove ice from sight glasses or viewing glasses? - ANSWERWER-An alcohol
spray
After installation of a field piped split system, the unit should first be pressurized with: -
ANSWERWERnitrogen and leak checked
Pressure relief valves can only be installed: - ANSWERWER-in parallel
How many access valves are needed to recover the refrigerant on a sealed system with an operating
compressor that has a completely restricted capillary tube? - ANSWERWER-Only one access valve, on
the high side of the system
What is the state of the refrigerant entering the compressor of a refrigerant system? - ANSWERWER-
Low pressure vapor
When first inspecting a hermetic system known to be leaking, you should look for: - ANSWERWER-
traces of oil
Why should low and high side access valves be installed when recovering refrigerant from a household
refrigerator? - ANSWERWER-To improve speed of recovery
