EPA 608 Study Guide
In which component of a system does the refrigerant change from a high-pressure vapor to a high-pressure liquid
Condenser
The low-side test-pressure data-plate value should be used by a technician to determine a safe pressure for
Leak testing
After refrigerant liquid transfer between recovery unit and the system being emptied you need to avoid trapping
Liquid refrigerant between service valves
Which international agreement (treaty) regulated the production and use of CFCs, HCFCs, halons, methyl chloroform and carbon tetrachloride
Montreal protocol
When can you use a disposable cylinder to recover refrigerant
Never
Ester-based oils can be mixed with
No the oils
It has been illegal to vent substitutes for CFC & HCFC refrigerants since
November 1995
When using nitrogen to pressurize a system you should
Only charge with nitrogen vapor
We dealing with small systems how many different refrigerants may be recovered into the same cylinder
Only one
What type of synthetic oils are commonly used in new HFC systems and for retrofitting HCFC equipment to HFC refrigerants
Polyester
Systems charged with R-134a should be leak checked with:
Pressurized nitrogen
Which of the following refrigerant has a GWP of "1"
R-1234ze
Which of the following refrigerants is an HFO
R-1234ze
Which refrigerant is an HCFC
R-124
If a technician has a system where some R-502 was added to a R-22 system. The technician should:
Recover all the refrigerant into a separate tank
Before you dispose of any system containing a refrigerant you must:
Recover the refrigerant
What must be done before disposing of any appliance containing a CFC, HCFC, or HFC refrigerant
Recover the refrigerant
During servicing of a refrigeration system containing R-12 The refrigerant must be:
Recovered
A cylinder with a gray body and a yellow top indicates that the cylinder is designed to hold:
Recovered refrigerant
____ Refers to the process of cleaning refrigerant by oil separation and single or multiple passes through filter-driers, which reduce moisture and acidity
Recycling
When using nitrogen in repairing a sealed refrigeration system, what should the nitrogen tank always be equipped with
Regulator
Which of the following repairs would always be considered "major" under EPA regulations
Replacement of an evaporator coil
It is the best practice to use dry nitrogen to break the vacuum when dehydrating by the triple evacuation method. However, it:
Requires a pressure regulator
Which of the following is true if a system will not hold the vacuum after it has been evacuated
The system may be leaking
An ozone molecule contains
Three oxygen atoms
The color code for approved refrigerant recovery cylinders is
Yellow tops and gray bodies
Approved refrigerant recovery cylinders can be identified by which color code
Yellow tops and grey bodies
Even though R-22 is considered non-toxic it:
can cause asphyxia
An award of up to what amount may be paid to a person supplying information that leads to a penalty against a technician who is intentionally venting
$10,000
How much can a person be fined per day per violation for knowingly releasing a regulated substance that violates the clean air act
$44,539
To scrap a disposable cylinder the internal cylinder pressure should be reduced to at least
0 psig
The high pressure gauge on service manifold sets has a continuous scale, usually calibrated to read from:
0-500 psi
A single chlorine atom can destroy how many ozone molecules
100,000
Each chlorine atom in the stratosphere can destroy ____ ozone molecules.
100,000
CFCs will no longer be manufactured or imported into the United States after:
1995
Reusable refrigerant containers that are normally under pressure above 15 psig, must be hydrostatically tested and date stamped every:
5 years
Reusable refrigerant containers under high-pressure must be hydrostatically tested how often
5 years
When an HFC system with POE oil has been opened for a major system repair what is the minimum evacuation level that should be achieved before charging the system
500 µm(microns)
A refillable refrigerant cylinder must never be filled to more than ________ of its capacity by weight:
80%
All recovery equipment currently being made is required to have
A EPA approved certification label
When a pungent order is detected during a sealed system recovery and/or repair which of the following is most likely
A compressor burnout has occurred
Ozone depletion potential or ODP is:
A measure of the ability of CFCs' and HCFCs' to destroy ozone.
It is necessary to place a refrigerant label on
A refrigerant cylinder which is being returned for reclaiming
What are the two factors that if present are most likely to lead to an explosion with hydrocarbon refrigerants
A sufficient concentration of the refrigerant in the space and an ignition source
The Montreal protocol is:
A treaty among nations that controls production of CFCs and HCFCs
According to ASHRAE's 1992 refrigerant safety classification, which designations is the most safe
A-1
Which ASHRAE classification means slightly flammable
A2L
Under EPA's regulations what standard must reclaimed refrigerant meet before I can be resold
ARI 700
Recycling and recovery equipment intended for use with air-conditioning and refrigeration equipment except for small appliances must be tested under
ARI 740
Which of the following is an approved "drop-in" service replacement for R-12
According to the EPA there are no drop in replacements
When moisture exists in an operating system which of the following is most likely to occur
Acid will form
The synthetic lubricant presently used with ternary blends containing HCFC's is:
Alkylbenzene
According to the EPA when dealing with customer complaints regarding additional costs due to refrigerant recovery efforts the technician should
All of the above
Data shows that chlorine in the stratosphere comes mainly from CFCs rather than from natural sources such as volcanoes because:
All of the above
Refrigeration technicians who violate the clean air act can
All of the above
Which safety precautions should always be followed
All of the above
R-410A is not a typical blended refrigerant because:
All of the above are true-it is a near azeotropic refrigerant and it can be charged as either a liquid or a vapor and while it has a 400 series refrigerant number it behaves like a 500 series refrigerant
What factors affect the speed of evacuation
All of the above including the size of the equipment being evacuated and the ambient temperature and the amount of moisture in the system
When using recovery unit the fill level of the recovery tank can be controlled by:
All of the above- mechanical float switch and electric shut off device and weight
When operating refrigerant recovery or recycling equipment the following precautions should always be followed
All of the above- including wear safety glasses wear protective gloves follow all safety precautions for the equipment
The recovery of refrigerants is necessary to:
All of the above- maintain adequate supplies for service calls after the production bans. prevent the venting of refrigerants to the atmosphere. prevent stratospheric ozone depletion.
Refrigerant cylinders should always be
All of the above-free of rust and damage and color-coded to indicate the contents and secure
Never use an open flame to heat a refrigerant tank because:
All of the above-it can result in venting refrigerant to the atmosphere and the tank may explode causing serious injury to people nearby and refrigerant in the tank may decompose forming a toxic material
Which refrigerant(s) must be recovered before opening a system or disposing of a system
All refrigerants must be recovered- R-410a , R-407c, R-134a
Use ___________________ to remove ice from a sight glass
An alcohol spray
What should be used to remove ice from sight glasses or viewing glasses
An alcohol spray
Which of the following human health effects could result from an increase in ultraviolet radiation
An increase in cataracts cases
What is the Montreal protocol
An international treaty that addresses O'zone depleting substances and their alternatives
A very large refrigerant leak can cause suffocation because refrigerants
Are heavier than air and displace oxygen
HCFC refrigerants:
Are less harmful to the stratospheric ozone in CFCs
In general blended refrigerants should be charged
As a liquid
To obtain an accurate vacuum readings during system evacuation the system vacuum gauge should be located colon
As far from the vacuum pump as possible
When evacuating a system the hoses should be
As short in length and as large in diameter as possible
The proper method of discarding a disposable refrigerant cylinder is to:
Assure that all refrigerant is recovered and that the cylinder is rendered useless then recycle the metal
When transporting cylinders containing used refrigerant the DOT requires that you:
Attach DOT classification tags
Which type of refrigerant is the most harmful to stratospheric ozone
CFC
Which of the following has the highest Ozone depletion potential
CFCs
Which type of refrigerant has the highest ozone depletion potential
CFCs
of the refrigerant listed below which refrigerant type have the highest ozone depletion potential
CFCs
Self-contained recovery devices:
Can capture liquid and or vapor refrigerant without the assistance of components in the air conditioning or refrigeration equipment
What is being done in the US. To stop Damage to the stratospheric ozone layer
Capturing and ultimately eliminating use of chlorofluorocarbons
Which of the following gases is used as the baseline measurement for global warming potential
Carbon dioxide
When evacuating a system the use of a severely oversized vacuum pump could
Cause trapped water to freeze
The condenser
Changes a high-pressure vapor to a high-pressure liquid
The compressor
Changes a low-pressure vapor to a high-pressure vapor
When using nitrogen to pressurize the system you should always:
Charge through a pressure regulator
The molecule found in CFCs and HCFCs that depletes ozone is
Chlorine
Which atom of the CFC molecule causes ozone depletion
Chlorine
The chemical was found in the upper stratosphere and that indicates that the ozone layer is being destroyed
Chlorine monoxide
Which leak repair category does the EPA define as air conditioning appliances used to provide cooling in order to control heat and humidity in occupied facilities including but not limited to residential, office, and commercial buildings
Comfort cooling
In a refrigeration system the device that changes a low pressure vapor to a high-pressure vapor is the:
Compressor
In a refrigeration system high pressure vapor is converted to high pressure liquid in the
Condenser
When dehydrating a system, the system can be heated to:
Decrease the dehydration time
Before shipping any used refrigerant cylinders check that the cylinder meets what standards
Department of transportation
Crop loss, eye disease, and skin cancer have been attributed to
Depletion of stratospheric ozone
Recover any remaining refrigerant and then render the cylinder useless then recycle the metal is the proper disposal method for
Disposable cylinders
The over-evacuation of a system
Does not occur
Which gases would cause the least amount of damage to the environment during a leak check
Dry nitrogen
What is the significant new alternatives policy (SNAP) program
EPA's program that identifies refrigerant with lower overall risks to human health and the environment
According to the EPA a ____________ leak detection methods is considered to be the most effective for locating the general area of a small leak
Electronic or ultrasonic tester
The type of oil that is most commonly used in stationary air conditioning applications with HFC -410a refrigerant is:
Ester oil
The type of oil that is most commonly used in stationary refrigeration applications with HFC-134a refrigerant is
Ester oil
Under the EPA safe disposal requirements the person responsible for making sure that the refrigerant has been removed from the household refrigerators before they are disposed of is the
Final person in the disposal chain
According to EPA regulations which of the following is procedures is not an approved technique for the system clean up after a burn out
Flushing with liquid refrigerant to clean tubing
Ozone depletion in the stratosphere is what type of problem
Global
A refrigerant cylinder designed to hold recovered refrigerant has a
Gray body and yellow top
Of the refrigerant listed below which types of refrigerant Will not damage stratospheric ozone
HFC's
Which type of refrigerants or chlorine free
HFC's
Which type of refrigerant contains no chlorine
HFCs
Silicone elastomers, for use in seals and gaskets, are not compatible with which refrigerants
HFOs
Personal protective equipment like gloves safety glasses safety shoes etc. should always be worn is when:
Handling and filling refrigerant cylinders
Refrigerant cannot be called "reclaimed" unless it
Has been chemically analyzed and the refrigerant meets the ARI-700 purity standard
Refrigerant leaves the condenser of an operating system as
High pressure liquid
What is the state of the refrigerant leaving the receiver in a refrigeration system
High pressure liquid
HFC refrigerant contain
Hydrogen fluorine and carbon
HCFCs contain
Hydrogen, fluorine, chlorine and carbon
Blended refrigerant leak from a system:
In uneven amounts due to different vapor pressures
Non-azeotropic refrigerant leak from a system
In uneven amounts due to different vapor pressures
What effect will low ambient temperatures have on recovery
Increase the recovery time
What is one of the most serious results of damage to the ozone layer
Increases in human skin cancer
The clean air act
Is all of the above including set a schedule for the phase out of CFC/HCFC Production and prohibits venting of refrigerant and authorizes the EPA to set standards for recovery of refrigerants
What statement is true about an azeotropic refrigerant mixture
It is a mixture that acts like a single component refrigerant over its entire range
It is illegal to
Knowingly release any refrigerant during the service maintenance repair or disposal of appliances with the exception of the de minimis releases
Refrigerant that enters the compressor under normal operating conditions is a
Low pressure vapor
What is the state of the refrigerant entering the compressor of a refrigeration system
Low pressure vapor
You can determine safe pressure for leak testing a system from the
Low side test pressure data plate value
When using with any solvent, cleaner, chemical or refrigerant you should review:
Material safety data sheets
After recovering refrigerant from a sealed system if nitrogen is used to pressurize or below debris out of the system the nitrogen
May be vented to the ambient air
What is the best proof that CFCs are in the stratosphere
Measurements of CFCs in air samples from the stratosphere
Ozone in the stratosphere above the earth consists of
Molecules of three oxygen atoms
Systems charged with R-410A should be leak checked with:
Pressurized nitrogen
A compound pressure gauge, typically used on the low side of the system, measure pressure in:
Psig and inches of mercury
Which refrigerant contains a CFC
R-12
Which refrigerant listed below is a "low-pressure"refrigerant under EPA's refrigerant recycling regulations
R-123
Which refrigerant is an HCFC?
R-123, R-124, R-22
Which of the following is a "very high pressure" refrigerant under EPA's refrigerant recycling regulations
R-13
An example of an HFC refrigerant is:
R-134a
Of the refrigerant listed below which has the lowest ozone potential
R-134a
An example of an HCFC refrigerant is
R-22
Which of the following is a high pressure refrigerant under EPA's refrigerant recycling regulations
R-22
Which refrigerant contains an HCFC
R-22
An example of a HFC refrigerant is:
R-410A
An example of an HFC refrigerant is:
R-410A
Which refrigerant contains a CFC
R-500
What is the component directly following the condenser in a refrigeration system using a thermal expansion valve
Receiver
__________ is the process that returns refrigerant to new product specifications and that requires chemical analysis
Reclaim
To process refrigerant to a level equal to new (virgin) product specifications as determined by chemical analysis defines
Reclaiming
The EPA requires the installation of a service aperture or process stub on all appliances is in a class 1 or class 2 substance as a refrigerant. The main purpose of this requirement is to make it easier to
Recovered refrigerant
__________ is the process of removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in anyway
Recovering
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 anyway
Recovery
After 1995 any supplies of CFC refrigerant to service existing units in the USA can only come from
Recovery and recycling
On a typical three port/3 hose manifold gauge the center port is used for
Recovery evacuation and charging
Clean refrigerant for reuse by separating the oil from the refrigerant and removing moisture from the refrigerant by passing it through one or more filter driers the definition of
Recycle
Manifold gauge sets are often color-coded when this is done the high pressure gauge is color-coded:
Red
In a vapor compressor refrigeration system cooling occurs when:
Refrigerant liquid turns to a vapor
What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine
Refrigerant that contain chlorine but not hydrogen are so stable that they do not break down in the lower atmosphere after being released. The chlorine or bromine reacts with Ozone causing it to change back to oxygen, thus destroying the ozone layer
Which type of refrigerant is the most harmful to stratospheric ozone
Refrigerants containing bromine
Which of the following refrigerant releases is a violation of the EPA Prohibition on venting
Release of mixtures of nitrogen and refrigerant that result from adding nitrogen to a fully charged appliance to "leak-check" the appliance
Which of the following refrigerant releases is considered a violation of the prohibition on venting
Release of mixtures of nitrogen and refrigerant that result from adding nitrogen to a fully charged appliance to leak test the appliance
If corrosion is found within the body of a relief valve the valve must be
Replaced
When corrosion is found within the body of a relief valve the valve must be
Replaced
The EPA can require a technician to demonstrate their ability to perform proper procedures for recovering and recycling refrigerant. Failure to demonstrate competency can result in
Revocation of the technician's certification
Refrigerant recovery during low ambient temperatures will
Slow the recovery process
Which of the following gases help form the earth's protective shield
Stratospheric ozone
Refrigerant entering the compressor of a refrigeration system is a
Superheated vapor
Recovery equipment that relies upon the pressure of the refrigerant in the appliance would be considered
System dependent
When a system will not hold the vacuum after has been evacuated then
System may be leaking
Recovery equipment that relies upon the compressor in the system would be considered:
System-dependent
What is the service procedure if the refrigerant in a recovery cylinder is suspected to be contaminated
Take a pressure reading of the cylinder
The term used to describe the fact that a refrigerant blend has a range of boiling or condensing points at a constant pressure is
Temperature glide
What does ozone depletion potential or ODP measure
The ability of a substance to destroy ozone in the stratosphere
Which of the following factors affect the speed of system dehydration
The ambient temperature and the amount of moisture in the system
To determine the maximum allowable pressure to use when checking a system check:
The design pressure on the equipment nameplate
Never overfill refrigerant storage cylinders because:
The internal pressure of the cylinder may rise in heated areas and cause an explosion
The size/capacity of the vacuum pump and the size of the suction line used will determine
The length of the dehydration time
R-134a has
The lowest ozone depletion potential
It is important not to mix R-22 and R-410a refrigerants in the same container because:
The mixture may be impossible to reclaim
It is important not to mix different refrigerants in the same container because:
The mixture may be impossible to reclaim
Refrigerant that is recovered can be returned to
The same system or other systems owned by the same person without restriction
According to the EPA an oil sample should be taken for which of the following reasons
The system had a leak or a major component failure
Measuring the systems final vacuum is always done with
The system isolated and the vacuum pump off
A system is considered dehydrated when
The vacuum indicator shows you have reached and held the required finished vacuum
Whenever dry nitrogen from a portable cylinder is connected to a system what item is of most importance in consideration of safety
There is a relief valve in the downstream line from the pressure regulator
According to the EPA, of the refrigerant listed below which types of refrigerant will not contribute to global warming
They all contribute to global warming-CFCs, HCFCs, HFC's
Why are some hydroflouroolefin(HFO) refrigerant classified as a "A2L"
They are less flammable than hydrocarbon refrigerants but most are still mildly flammable
Which of the following best describes low loss fittings on refrigerant recovery devices used to recover CFCs, HCFCs, and HFCs
They can be either manually closed or automatically closed when disconnected to prevent loss of refrigerant from hoses
Refrigerant vapors or mess should not be inhaled because:
They may cause heart irregularities and/or unconsciousness
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFC) have which of the following in common
They must be recovered before opening or disposing of appliances
Which of the following statements about "self contained" recovery devices is true
They remove refrigerant from an appliance without the assistance of components in the appliance
A ternary refrigerant blend is a____________ part mixture
Three-part
What is the best use for testing with soap bubbles
To pinpoint refrigerant leaks
The ozone layer protects the earth from:
Ultraviolet radiation from the sun
How should refrigerant cylinders be positioned when they are shipped
Upright
How would you remove moisture from refrigerant in a system
Use a filter drier
Which of the following safety precautions should be adhered to for low pressure systems
Use gloves and safety goggles when working with liquid refrigerant
Refrigerant migrates to the compressor crank case because of a difference in _________ between the refrigerant and the oil
Vapor pressure
Disposable refrigerant containers are used for ______ refrigerant
Virgin
Which of the following are recommended safe work practices when recovering refrigerants
Wear safety eyewear and butyl-lined gloves when connecting/disconnecting hoses
Never use oxygen or compressed air to pressurize the system because
When mixed with compressor oil or some refrigerant it could explode
HFCs
Will not damage stratospheric ozone but have a high GWP
The chlorine in CFCs and HCFCs
Will not dissolve in water
In what state should a system be to measure a final system vacuum
With the system isolated and the vacuum pump turned off
Technicians receiving a passing grade on the type two: (medium-pressure, high-pressure and very high pressure) exam are certified to recover refrigerant during the maintenance, service or repair of medium and high pressure equipment and very high pressure refrigerant including:
With type two certification you are certified for all very high pressure refrigerants including CFC-13 and CFC-503
Equipment covered by EPA regulations include:
all air-conditioning and refrigeration equipment using CFC, HCFC or HFC refrigerants.
CFC refrigerant are so named because they contain the elements:
chlorine fluorine and carbon
The evacuation of a system is a method of
dehydration
When evacuating the system the hoses should be
equal to or larger than the vacuum pump inlet connection
HCFC refrigerants contain:
hydrogen chlorine fluorine carbon
Before beginning a refrigerant recovery procedure it is always necessary to
know the type of refrigerant that is in the system
Refrigerant that enters the expansion or throttling device also known as the metering device is a
liquid
All devices used for refrigerant recovery must:
meet EPA standards
If an oil is hygroscopic it means that it:
readily absorbs oil
A system is dehydrated to:
remove water and water vapor
A hermetic compressor must never be operated when:
there is a dehydration vacuum in the system
Containers designated "refillable" by DOT are used for transporting recovered pressurized refrigerant
to meet safety requirements
Which chemicals are controlled by the Montreal protocol
All of the above - chlorofluorocarbons and hydrochlorofluorocarbons and halons
Long hoses between the unit and the recovery machine should not be used because they cause:
All of the above - excessive pressure drop increased recovery time and increased emissions
Of the items listed below which is and are violations of the clean air act
All of the above - falsifying or failing to keep required records and failing to reach required a evacuation levels before opening or disposing of appliances and knowingly releasing CFC or HCFC refrigerant or their substitutes while repairing appliances
What effects can ozone depletion have on the environment
All of the above - reduced crop yields and reduced marine life and increased ground level ozone
which of the following statements would be considered good service practices for conserving refrigerant
All of the above -recover recycle refrigerant and keep systems tight and find and repair leaks
Manifold gauge sets are often color coded, when this is done, the low pressure gauge is color coded:
Blue
State and local governments can make state laws that
Both A and B- follow the clean air act/EPA regulations and contain stricter regulations then those acts
