AHR-110 Exam 3 Questions and Answers Graded A+
The most common type of system leaks are __________ leaks. - Answers Standing
A(n) ____________ leak detector requires a lubricant-specific dye be injected into a charged system to
find the leak. - Answers Ultraviolet
Removing air and/or other noncondensable gases from a system using a vacuum pump is called
___________. - Answers Degassing
The process of removing both noncondensable gases and water vapor is called ________. - Answers
Evacuation
Sludge and other solids can be removed from a system by using __________. - Answers liquid- and
suction-line filter/driers
Atmospheric pressure, 0 psig, is the equivalent of about __________ microns. - Answers 760,000
(T/F): The process of a solid changing to a vapor without passing through the liquid state is called
dehydration. - Answers False
(T/F): A system with Schrader valve gauge ports will take longer to evacuate than a system with service
valves. - Answers True
A ¼ inch service hose will only allow a vacuum pump to pull at _____ CFM, regardless of the pump's
CFM rating. - Answers 0.8
The mechanical strain of motion, rotation, and refrigerant flow are all associated with _________ leaks. -
Answers Vibration-Dependent
The low-pressure side of the system must not be pressurized to more than_________ when testing for
leaks. - Answers The low-side design pressure
Standing, pressure-dependent, temperature-dependent, vibration-dependent, combination-dependent,
and micro are all types of - Answers Leak Methods
The _____________ is both the greatest asset and the greatest liability of an electronic leak detector. -
Answers Sensitivity
A deep vacuum can most accurately be measured in - Answers Microns
Which of the tools used during the evacuation process can be wireless and use Bluetooth technology? -
Answers Micron Gauge
A ___________ can remove any type of foreign matter that enters a refrigeration system. - Answers
Filter Drier
, Moisture, acid buildup, and copper plating can all be caused by which of the following? - Answers Air in
the System
The only two substances that should be circulating in a refrigeration system are - Answers Refrigerant
and Oil
In order to remove moisture from a refrigeration system using a vacuum pump, it must be in a
____________state. - Answers Vapor
When checking for a leak in the evaporator coil, the leak detector can be placed - Answers In the drain
outlet
Two types of evacuation methods used by technicians are - Answers Deep vacuum and triple
evacuation.
An evacuation process that is performed a number of times with nitrogen being used to break the
vacuum, and ends with a deep vacuum is known as - Answers Triple Evacuation
A system that is equipped with a _____________ may require additional steps to ensure that the entire
system is evacuated. - Answers Solenoid Valve
The most accurate type of gauge for measuring a deep vacuum is a - Answers Digital Micron Gauge
A system that contains less than ______ of refrigerant does not require a leak to be repaired, but it is
recommended to do so. - Answers 50 lb
Which of the following conditions requires a system cleanup, an oil test, and oversized filters to be
added to the system? - Answers A compressor motor burnout
A large refrigeration system that contains a significant amount of moisture should be evacuated with -
Answers A high CFM vacuum pump
Proper maintenance for a vacuum pump would include which of the following? - Answers Changing the
oil as often as necessary
When a deep vacuum is reached (500 microns), the system valved and observed for 10 to 15 minutes. A
rise in pressure could indicate which of the following? - Answers There may be a leak or the presence of
air and/or moisture
One of the advantages of a microfoam leak detection solution over standard bubble solutions is that it -
Answers Will not pit or corrode the components
An oily dust spot on a condenser or evaporator coil could indicate - Answers A refrigerant leak
When leak checking the suction line with an electronic leak detector, the probe should be placed -
Answers Under the pipe insulation
The most common type of system leaks are __________ leaks. - Answers Standing
A(n) ____________ leak detector requires a lubricant-specific dye be injected into a charged system to
find the leak. - Answers Ultraviolet
Removing air and/or other noncondensable gases from a system using a vacuum pump is called
___________. - Answers Degassing
The process of removing both noncondensable gases and water vapor is called ________. - Answers
Evacuation
Sludge and other solids can be removed from a system by using __________. - Answers liquid- and
suction-line filter/driers
Atmospheric pressure, 0 psig, is the equivalent of about __________ microns. - Answers 760,000
(T/F): The process of a solid changing to a vapor without passing through the liquid state is called
dehydration. - Answers False
(T/F): A system with Schrader valve gauge ports will take longer to evacuate than a system with service
valves. - Answers True
A ¼ inch service hose will only allow a vacuum pump to pull at _____ CFM, regardless of the pump's
CFM rating. - Answers 0.8
The mechanical strain of motion, rotation, and refrigerant flow are all associated with _________ leaks. -
Answers Vibration-Dependent
The low-pressure side of the system must not be pressurized to more than_________ when testing for
leaks. - Answers The low-side design pressure
Standing, pressure-dependent, temperature-dependent, vibration-dependent, combination-dependent,
and micro are all types of - Answers Leak Methods
The _____________ is both the greatest asset and the greatest liability of an electronic leak detector. -
Answers Sensitivity
A deep vacuum can most accurately be measured in - Answers Microns
Which of the tools used during the evacuation process can be wireless and use Bluetooth technology? -
Answers Micron Gauge
A ___________ can remove any type of foreign matter that enters a refrigeration system. - Answers
Filter Drier
, Moisture, acid buildup, and copper plating can all be caused by which of the following? - Answers Air in
the System
The only two substances that should be circulating in a refrigeration system are - Answers Refrigerant
and Oil
In order to remove moisture from a refrigeration system using a vacuum pump, it must be in a
____________state. - Answers Vapor
When checking for a leak in the evaporator coil, the leak detector can be placed - Answers In the drain
outlet
Two types of evacuation methods used by technicians are - Answers Deep vacuum and triple
evacuation.
An evacuation process that is performed a number of times with nitrogen being used to break the
vacuum, and ends with a deep vacuum is known as - Answers Triple Evacuation
A system that is equipped with a _____________ may require additional steps to ensure that the entire
system is evacuated. - Answers Solenoid Valve
The most accurate type of gauge for measuring a deep vacuum is a - Answers Digital Micron Gauge
A system that contains less than ______ of refrigerant does not require a leak to be repaired, but it is
recommended to do so. - Answers 50 lb
Which of the following conditions requires a system cleanup, an oil test, and oversized filters to be
added to the system? - Answers A compressor motor burnout
A large refrigeration system that contains a significant amount of moisture should be evacuated with -
Answers A high CFM vacuum pump
Proper maintenance for a vacuum pump would include which of the following? - Answers Changing the
oil as often as necessary
When a deep vacuum is reached (500 microns), the system valved and observed for 10 to 15 minutes. A
rise in pressure could indicate which of the following? - Answers There may be a leak or the presence of
air and/or moisture
One of the advantages of a microfoam leak detection solution over standard bubble solutions is that it -
Answers Will not pit or corrode the components
An oily dust spot on a condenser or evaporator coil could indicate - Answers A refrigerant leak
When leak checking the suction line with an electronic leak detector, the probe should be placed -
Answers Under the pipe insulation
