EPA 608 CERTIFICATION EXAM|| LATELY UPDATED QUESTIONS 2024-2025 WITH 100% CORRECT ANSWER, Exams of Nursing

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EPA 608 UNIVERSAL EXAM 202 4 - 2025 ACTUAL EXAM

ALL 250 QUESTIONS AND CORRECT DETAILED

ANSWERS WITH RATIONALES (VERIFIED ANSWERS)

|ALREADY GRADED A+

What are two factors that, if present, are most likely to lead to an explosion with hydrocarbon refrigerants? - ANSWER-A sufficient concentration of the refrigeration in the space and an ignition source An appliance normally containing more than 50 pounds of R-22 refrigerant was found to have a 35% annual leak rate. After the repair, how many successful verification tests are required? - ANSWER-Two. Performed before the appliance is recharged All appliances must be equipped with a service aperture or process stub which is used when adding or removing refrigerant from the appliance. What is typically used on small appliances? - ANSWER-A straight piece of tubing that is entered using a piercing access valve. Process Tube What is the primary purpose of a purge unit on a low-pressure chiller? - ANSWER-Remove noncondensable from the system Which of the following are recommended safe work practices when recovering refrigerants? - ANSWER- Wear safety eyewear and butyl-lined gloves when connecting/disconnecting hoses What is the state of the refrigerant leaving the receiver in a refrigeration system? - ANSWER-High pressure liquid Which of the following repairs would always be considered "major" under EPA's regulations? - ANSWERReplacement of an evaporator coil On low-pressure chillers, moisture most frequently enters the refrigeration system through: - ANSWERLeaks from areas with gaskets or fittings How would you remove moisture from refrigerant in a system? - ANSWER-Use a filter drier

Where does refrigerant go after it leaves the purge unit of a low-pressure centrifugal system? - ANSWER- The evaporator Which refrigerants can be mixed in an appliance? - ANSWER-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? - ANSWER-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? - ANSWER-Recovery What is meant by the term "high efficiency purge unit"? - ANSWER-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: - ANSWER-know the type of refrigerant in the system Which of the following gases is used as the baseline measurement for global warming potential? - ANSWER-Carbon Dioxide Which hydrocarbon refrigerant is approved for retrofit into existing household refrigerators? - ANSWERHC R-600a 2 ounces or less Recovered refrigerant may contain which of the following impurities? - ANSWER-Acids, moisture, and oil A hydrostatic tube test kit will - ANSWER-determine if a lube leaks When installing any type of access fitting onto a sealed system: - ANSWER-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? - ANSWER-Within 10 days

Why are some hydrofluoroolefin (HFO) refrigerants classified as "A2L"? - ANSWER-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? - ANSWER-Use of calculations based on component and pipe sizes When could a reciprocating compressor be damaged if energized? - ANSWER-When the discharge service valve is closed Which of the following are included in EPA's definition of a "small appliance"? - ANSWER-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?

• ANSWER-Oil Which of the following is an indicator of a leak in a high-pressure system with a capillary tube? - ANSWER-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: - ANSWER-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? - ANSWER-When using self-contained recovery devices Excessive running of a purge system on a low-pressure chiller generally indicates what condition? - ANSWER-Leaking system Which of the following always falls under the EPA definition for "major maintenance, service, or repair"?
• ANSWER-Replacing a compressor What effect will low ambient temperatures have on recovery? - ANSWER-Increase the recovery time

What should be used to remove ice from sight glasses or viewing glasses? - ANSWER-An alcohol spray After installation of a field piped split system, the unit should first be pressurized with: - ANSWERnitrogen and leak checked Pressure relief valves can only be installed: - ANSWER-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? - ANSWER-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? - ANSWER-Low pressure vapor When first inspecting a hermetic system known to be leaking, you should look for: - ANSWER-traces of oil Why should low and high side access valves be installed when recovering refrigerant from a household refrigerator? - ANSWER-To improve speed of recovery What is the Montreal Protocol? - ANSWER-An international treaty that addresses ozone-depleting substances and their alternatives A rupture disc on a recovery vessel for low-pressure refrigerants relieves at: - ANSWER-15 psig What must be done before disposing of any appliance containing a CFC, HCFC, or HFC refrigerant? - ANSWER-Recover the refrigerant What must a system owner do once the threshold leak rate has been exceeded on any low-pressure system using an ozone-depleting refrigerant? - ANSWER-Repair the appliance enough to bring the leak rate below the threshold, retrofit, or retire the appliance

What may be done to speed the recovery process and ensure that all CFC, HCFC, or HFC refrigerant has been removed from a frost-free refrigerator? - ANSWER-Turn on the defrost heater to increase the refrigerant's temperature and vaporize any liquid When using a self-contained recovery device on a CFC, HCFC, or HFC system with an operating compressor, technicians must: - ANSWER-either recover the refrigerant to 4 inches of mercury vacuum or 90% of the nameplate charge What is the maximum allowable factory charge of refrigerant for Type I appliances using CFCs, HCFCs, or HFCs? - ANSWER-5 pounds How should refrigerant cylinders be positioned when they are shipped? - ANSWER-upright A company uses a chiller that diverts 55% of its cooling capacity to one of its manufacturing lines and 45% of its cooling capacity to air condition the office spaces. Which leak rate category would this chiller be in? - ANSWER-Industrial process refrigeration Which type of refrigerant has the highest ozone depletion potential (ODP)? - ANSWER-HFCs Which of the following refrigerant releases is considered a violation of the prohibition on venting? - ANSWER-Release of mixtures of nitrogen and refrigerant that result from adding nitrogen to a fully charged appliance to leak check the appliance Starting in 2019, what is the leak rate threshold for commercial refrigeration equipment with a full charge of 50 or more pounds of an HCFC refrigerant? - ANSWER-0. In which component of a system does the refrigerant change from a high-pressure vapor to a highpressure liquid? - ANSWER-Condenser Which of the following factors affect the speed of system dehydration? - ANSWER-The ambient temperature and amount of moisture in the system During evacuation with large amounts of moisture it may be necessary to increase pressure to counteract freezing with gas such as - ANSWER-Nitrogen

When using nitrogen in repairing a sealed refrigeration system, what should the nitrogen tank always be equipped with? - ANSWER-Regulator After refrigerant liquid has been been recovered from the appliance, any remaining vapor is: - ANSWERremoved by the recovery system After system servicing, and recharging, why is refrigerant vapor re-introduced to the chiller before refrigerant liquid? - ANSWER-Vapor charging increases pressure slowly, preventing failure of the rupture disk Approved refrigerant recovery cylinders can be identified by which color code? - ANSWER-Yellow tops and gray bodies When corrosion is found within the body of a relief valve, the valve must be: - ANSWER-Replaced Which of the following statements about "self-contained" recovery devices is true? - ANSWER-They remove refrigerant from an appliance without the assistance of components in the appliance In what state should a system be to measure a final system vacuum? - ANSWER-With the system isolated and vacuum pump turned off Which of the following safety precautions should be adhered to for low-pressure systems? - ANSWER- Use gloves and safety goggles when working with liquid refrigerant If a reclamation facility receives a tank of mixed refrigerant, they may; - ANSWER-refuse to accept the refrigerant or charge extra for processing it When a pungent odor is detected during a sealed system recovery and/or repair which of the following is most likely? - ANSWER-A compressor burnout has occured What is a characteristic of a refrigerant oil that is hygroscopic? - ANSWER-It readily absorbs moisture

Which of the following is an approved refrigerant for new household refrigerators, freezers, and combination refrigeration/freezers? - ANSWER-R-600a Which of the following indicates air in a low-pressure system? - ANSWER-High head pressure Which of the following should be replaced if a system is opened for servicing? - ANSWER-Filter drier What is the service procedure if the refrigerant in a recovery cylinder is suspected to be contaminated? - ANSWER-Discard the refrigerant Why do chillers using low-pressure refrigerants require purge units? - ANSWER-These systems operate below atmospheric pressure Where should the discharge from a rupture disc be piped for venting? - ANSWER-Outdoors A passive system-dependent recovery process for small appliances; - ANSWER-still uses a pump to recover refrigerant It is best practice to use dry nitrogen to break the vacuum when dehydrating by the triple evacuation method. However, it: - ANSWER-requires a pressure regulator Which leak repair category does the EPA define as air-conditioning appliances used to provide cooling in order to control heat and/or humidity in occupied facilities including, but not limited to, residential, office, and commercial buildings? - ANSWER-comfort cooling Where would you place a leak detector probe to check gas leaks into the water box with water removed?

• ANSWER-in the drain valve opening Which of the following best describes low loss fittings on refrigerant recovery devices used to recover CFCs, HCFCs, and HFCs? - ANSWER-They are used to connect the recovery device to an appliance and leak only small amounts of refrigerant during use In the event of a large release of CFC, HCFC, or HFC refrigerant in a contained area which of the following is true? - ANSWER-Self-contained breathing apparatus (SCBA) or leaving the area is required

After recovering refrigerant from a sealed system, if nitrogen is used to pressurize or blow debris out of system, the nitrogen: - ANSWER-may be vented to the ambient air The EPA's leak repair requirements apply to appliances with a charge size of - ANSWER-50 pounds or greater A very large refrigerant leak can cause suffocation because refrigerants: - ANSWER-are heavier than air displace oxygen ASHRAE Standard 15-2013 requires the use of room sensors and alarms to detect: - ANSWER-refrigerant leaks When leak testing a low-pressure centrifugal chiller with nitrogen, what is the maximum test pressure? - ANSWER-10 psig What is the maximum normal charge of HCFC or HFC refrigerant in an appliance that is allowed to use system dependent recovery equipment? - ANSWER-15 pounds Where is the rupture disc located on a centrifugal chiler? - ANSWER-Evaporator What is the component directly following the condenser in a refrigeration system using a thermal expansion valve? - ANSWER-Receiver What does ozone depletion potential (or "ODP") measure? - ANSWER-The ability of a substance to destroy ozone in the stratosphere A comfort-cooling appliance containing 50 pounds or more of R-22 is found to be leaking beyond the applicable leak rate threshold. Unless granted additional time, how many days do you have to repair the leak and conduct the initial leak verification test? - ANSWER-30 days Which of the following is true if a system will not hold a vacuum after it has been evacuated? - ANSWERThe system may be leaking

For which of the following refrigeration systems/appliances would it be permissible to use a passive recovery device for recovery of CFCs, HCFCs, and HFCs? - ANSWER-A domestic refrigerator Why could a recycling or recovery machine that uses a hermetic compressor overheat when drawing deep vacuums? - ANSWER-The motor relies on the flow of refrigerant through the compressor for cooling When evacuating a system, the use of a severely oversized vacuum pump could: - ANSWER-cause trapped water to freeze What is the best use for testing with soap bubbles? - ANSWER-To pinpoint refrigerant leaks Which condition can cause excessive pressure on the high side of a self-contained (active) recovery device? - ANSWER-When there is a large volume of non-condensable gas in the refrigerant being recovered Why should the oil be removed from a low-pressure system at 130°F? - ANSWER-Less refrigerant will be contained in the oil at the higher temperature Your recovery/recycling machine has R-22 refrigerant in it. You now have to recover refrigerant from an R-410A unit. What must be done before recovery? - ANSWER-Change the recovery cylinder on the recovery machine A customer has an industrial process refrigeration system that contains 1000 lbs. of R-22 that has exceeded the applicable leak rate threshold. How often is the customer required to perform a leak inspection? - ANSWER-Every 3 months 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? - ANSWER-500 microns Refrigeration technicians who violate the Clean Air Act can: - - ANSWER-Lose their EPA certification, be fined, be required to appear in Federal court. After 1995, any supplies of CFC refrigerants to service existing units in the USA can only come from: - - ANSWER-recovery and recycling.

Refrigerant that is recovered can be returned to: - - ANSWER-the same system or other systems owned by the same person without restriction. Refrigerant can not be called "reclaimed" unless it: -. - ANSWER-has been chemically analyzed and the refrigerant meets the ARI-700 standard. The EPA can require a technician to demonstrate their ability to perform proper procedures for recovering and/or recycling refrigerant. Failure to demonstrate competency can result in: - - ANSWERrevocation of the technicians certification. What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine? - - ANSWER-Refrigerants 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 the ozone, causing it to change back to oxygen, thus destroying the ozone layer. A system is considered dehydrated when: - - ANSWER-the vacuum indicator shows you have reached and held the required finished vacuum. Disposable refrigerant containers are used for ______ - ANSWER-virgin refrigerant Which refrigerant is an HCFC? - - ANSWER-R-123, R-124, R- 22 What statement is true about an azeotropic refrigerant mixture? - - ANSWER-It is a mixture that acts like a single-component refrigerant over its entire range. Chlorofluorocarbos (CFCs) and hydrochlorofluorocarbons (HCFCs) have which of the following in common? - - ANSWER-It is a mixture that acts like a single-component refrigerant over its entire range. To scrap a disposable cylinder, the internal cylinder pressure should be reduced to at least: - - ANSWER psig. Manifold gauge sets are often color coded, when this is done, the high pressure gauge is color coded: - Red. - ANSWER-

In general, blended refrigerants should be charged: - - ANSWER-as a liquid. Blended refrigerants leak from a system: - - ANSWER-in uneven amounts due to different vapor pressures. Which of the following gases help form the earth's protective shield? - Stratospheric Ozone - ANSWER- In a refrigerant system, the device that changes a low pressure vapor to a high pressure vapor is the: - compressor. - ANSWER- Data shows that chlorine in the stratosphere comes mainly from CFCs rather than from natural sources such as volcanoes because: - The rise in the amount of chlorine in the stratosphere matches the rise in the amount of fluorine, which has different natural sources than chlorine; The rise in the amount of chlorine in the stratosphere matches the rise in CFC emissions; Air samples taken from the stratosphere over erupting volcanoes show that volcanoes contribute a small quantity of chlorine to the stratosphere when compared to CFCs; - ANSWER- Which atom of the CFC molecule causes ozone depletion? - chlorine - ANSWER- The ozone layer protects the earth from: - ultraviolet radiation from the sun. - ANSWER- When using with any solvent, cleaner, chemical or refrigerant, you should review: - material safety data sheets. - ANSWER- 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 - ANSWER- The Montreal Protocol is: - a treaty among nations that controls production of CFCs and HCFCs. - ANSWER- Which refrigerant is an HCFC? - R-123, R-22, R- 124 - ANSWER- What is one of the most serious results of damage to the ozone layer? - increases in human skin cancer - ANSWER-

Of the refrigerants listed below, which has the lowest ozone depletion potential (ODP)? - R- 22 - ANSWER- To determine the maximum allowable pressure to use when checking a system, check: - the design pressure on the equipment nameplate - ANSWER- Ozone depletion potential, or "ODP," is: - A measure of the ability of CFCs and HCFCs to destroy ozone. - ANSWER- An example of an HFC refrigerant is: - R-134a - ANSWER- Whenever dry nitrogen from a portable cylinder is connected to a system, what item is of most importance in consideration of safety? - There is relief in the downstream line from the pressure regulator. - ANSWER- During servicing of a refrigeration system containing R-12, the refrigerant must be: - recovered. - ANSWER- Which safety precaution(s) should always be followed: - Never apply an open flame to a refrigerant cylinder; never cut or weld any refrigerant line when refrigerant is in the line; never use oxygen to purge lines or to pressurize a system. - ANSWER- In a vapor compression refrigeration system, cooling occurs when: - refrigerant liquid turns to a vapor. - ANSWER- The evacuation of a system is a method of: - dehydration. - ANSWER- Each chlorine atom in the stratosphere can destroy____ozone molecules. - 100,000 - ANSWER- An example of a HFC refrigerant is: - R-410A - ANSWER- Which gas(es) would cause the LEAST damage to the environment during a leak check? - dry nitrogen - ANSWER-

Refrigerant migrates to the compressor crankcase because of a difference in______between the refrigerant and the oil. - vapor pressure. - ANSWER- Which refrigerant is an HCFC? - R-22, R-123, R- 124 - ANSWER- It is important not to mix R-22 and R-410A refrigerants in the same container because: - the mixture may be impossible to reclaim. - ANSWER- When using recover unit, the fill level of the recovery tank can be controlled by: - a mechanical switch; an electronic shut-off device; weight - ANSWER- 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. - ANSWER- Which of the following human health effects could result from an increase in ultraviolet radiation? - an increase in cataracts cases - ANSWER- Never use an open flame to heat a refrigerant tank because: - it can result in venting refrigerant to the atmosphere; the tank may explode, causing serious injury to people nearby; refrigerant in the tank may decompose, forming a toxic material. - ANSWER- When transporting cylinders containing used refrigerant, the DOT requires that you: - attach DOT classification tags - ANSWER- According to ASHRAE's 1992 refrigerant safety classification which of the following designations would be the most safe? - A- 1 - ANSWER- The over-evacuation of a system: - does not occur. - ANSWER- Equipment covered by EPA regulations include: - all air-conditioning and refrigeration equipment using CFC, HCFC or HFC refrigerants. - ANSWER-

Never overfill refrigerant storage cylinders because: - the internal pressure of the cylinders may rise in heated areas and cause an explosion. - ANSWER- It is important not to mix different refrigerants in the same container because: - the mixture may be impossible to reclaim. - ANSWER- Manifold gauge sets are often color coded, when this is done, the low pressure gauge is color coded: - blue. - ANSWER- All devices used for a refrigerant recovery must: - Meet EPA standards - ANSWER- Reusable refrigerant containers that are normally under any pressure above 15 pig must be hydrostatically tested and date stamped every: - 5 Years - ANSWER- Which refrigerant(s) must be recovered before opening a system or disposing of a system? - all refrigerants must be recovered. - ANSWER- To obtain an accurate vacuum readings during system evacuation, the system vacuum gauge should be located: - as far from the vacuum pump as possible. - ANSWER- What is the best proof that CFCs are in the stratosphere? - measurements of CFCs in air samples from the stratosphere - ANSWER- The recovery of refrigerants is necessary to: - maintain adequate supplies for service calls after the production bans; prevent the venting of refrigerants to the atmosphere; prevent stratospheric ozone depletion - ANSWER- An example of an HFC refrigerant is: - R-410A - ANSWER- A compound pressure gauge, typically used on the low side of the system, measures pressure in: - psig and inches of mercury - ANSWER-

______________refers to the process of cleaning refrigerant by oil separation and single or multiple passes through filter-driers, which reduce moisture and acidity? - Recycling - ANSWER- The high pressure gauge on service manifold sets has a continuous scale, usually calibrated to read from:

• 0 to 500 psi - ANSWER- _________is the process that returns refrigerant to new-product specifications and that requires chemical analysis? - Reclaim - ANSWER- A cylinder with a gray body and a yellow top indicates that the cylinder is designed to hold: - recovered refrigerant - ANSWER- HFC refrigerants: - are less harmful to stratospheric ozone than CFCs - ANSWER- Which type of refrigerant is the most harmful to stratospheric ozone? - Refrigerants containing Bromine
• ANSWER- According to the EPA, a_______ leak detection method is considered to be the most effective for locating the general area of a small leak. - electronic or ultrasonic tester - ANSWER- Long hoses between the unit and the recovery machine should not be used because they cause: - excessive pressure drop; increased recovery time; increased emissions - ANSWER- Recovery equipment that relies upon the compressor in the system would be considered: - systemdependent. - ANSWER- A hermetic compressor must never be operated when: - there is a dehydration vacuum in the system. - ANSWER- "Self-contained" recovery devices: - can capture liquid and/or vapor refrigerant without the assistance of components in the air-conditioning or refrigeration equipment. - ANSWER- Systems charged with R-410A should be leak checked with: - pressurized nitrogen. - ANSWER-

R-410A is not a typical blended refrigerant because: - It is near azeotropic refrigerant; it can be charged as either a liquid or vapor; while it has a 400 series refrigerant number it behaves like a 500 series refrigerant - ANSWER- A ternary refrigerant blend is a _______ part mixture. - three-part - ANSWER- In a refrigeration system, high pressure vapor is converted to high pressure liquid in the: - condenser. - ANSWER- Which of the following is an approved "drop-in" service replacement for r-12? - According to the EPA there are no "drop-in" replacements - ANSWER- 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. - ANSWER- CFC refrigerants are so named because they contain the elements: - Chlorine, fluorine, carbon - ANSWER- Before you dispose of any system containing a refrigerant, you must: - recover the refrigerant. - ANSWER- According to EPA regulations, which of the following is procedures is NOT an approved technique for system cleanup after a burnout? - flushing with liquid refrigerant to clean tubing - ANSWER- When using nitrogen to pressurize a system, you should always: - charge though a pressure regulator. - ANSWER- What effects can ozone depletion have on the environment? - reduced crop yields; reduced marine life; increased ground-level ozone - ANSWER- Non-azeotropic refrigerants leak from a system: - in uneven amounts due to different vapor pressures. - ANSWER-

An example of an HCFC is: - R- 22 - ANSWER- Which chemicals are controlled by the Montreal Protocol? - chlorofluorocarbons, hydrochlorofluorocarbons, halons - ANSWER- Systems charged with R-134a should be leak checked with: - pressurized nitrogen. - ANSWER- When evacuating a system, the hoses should be: - equal to or larger than vacuum pump inlet connection.

• ANSWER- It has been illegal to vent substitutes for CFC and HCFC refrigerants since: - November 1995 - ANSWER- Never use oxygen or compressed air to pressurize a system because: - when mixed with compressor oil or some refrigerants, it could explode. - ANSWER- Refrigerant cylinders should always be: - free of rust and damage; color coded to indicate the contents; secure - ANSWER- Even though R-22 is considered non-toxic, it: - can cause asphyxia. - ANSWER- A system is dehydrated to: - remove water and water vapor. - ANSWER- According to the EPA, of the refrigerants liked below, which types of refrigerants will not contribute to Global Warming? - CFCs HCFCs HFCs all contribute to Global Warming - ANSWER- The type of oil that is most commonly used in stationary air conditioning applications with HFC-410A refrigerant is: - ester oil. - ANSWER- Technicians receiving a passing grade on the Type II (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 refrigerants, including: - With Type II certification, you are certified for all very high pressure refrigerants including CFC-13 and CFC- 503 -

ANSWER-

PPE(gloves, safety glasses, safety shoes, etc.) should always be worn is when: - handling and filling refrigerant cylinders. - ANSWER- Refrigerant vapors or mist should not be inhaled because - they may cause heart irregularities and/or unconsciousness. - ANSWER- Violations of the Clean Air Act? - falsifying or failing to keep required records; failing to reach required evacuation levels before opening or disposing of appliances; knowingly releasing CFC or HCFC refrigerants or their substitutes while repairing appliances. - ANSWER- HFC refrigerants contain: - hydrogen, fluorine, carbon - ANSWER- Which refrigerant contains an HCFC? - R- 22 - ANSWER- Recovery equipment that relies upon the pressure of the refrigerant in the appliance would be considered: - System-dependent - ANSWER- Refrigerant that enters the compressor, under normal operating conditions, is a: - low pressure vapor. - ANSWER- It is necessary to place a refrigerant label on: - a refrigerant cylinder which is being returned for reclaiming. - ANSWER- Which refrigerant contains a CFC? - R- 500 - ANSWER- Use________ to remove ice from a sight glass. - an alcohol spray. - ANSWER- According to the EPA, an oil sample should be taken for which of the following reasons? - They system had a leak or a major component failure. - ANSWER-

The EPA requires the installation of a service aperture or process stub on all appliances using a class I or class II substance as a refrigerant. The main purpose of this requirement is to make it easier to: - recover refrigerant. - ANSWER- Recycling and recovery equipment intended for use with air-conditioning and refrigeration equipment(except for small appliances) must be tested under: - ARI 740 - ANSWER- Refrigerant entering the compressor of a refrigeration system is a: - superheated vapor. - ANSWER- What is being done in the U.S. to stop damage to the stratospheric ozone layer? - capturing and ultimately eliminating use of chlorofluorocarbons. - ANSWER- They type of oil that is most commonly used in stationary refrigeration applications with HFC-134a refrigerant is: - ester oil. - ANSWER- The term used to describe the fact that a refrigerant blend has a range of boiling or condensing pints at a constant pressure is: - temperature glide. - ANSWER- Which refrigerant contains a CFC? - R- 12 - ANSWER- Under EPA's regulations, what standard must reclaimed refrigerant meet before it can be resold? - ARI 700 - ANSWER- An example of a HFC refrigerant is: - R-134a - ANSWER- It is illegal to: - knowingly release any refrigerant during the service, maintenance, repair or disposal of appliances, with the exception of de minimis releases. - ANSWER- Which type of refrigerant is the most harmful to stratospheric ozone? - CFC - ANSWER-

Refrigerant that enters the expansion or throttling device (also known as the metering device) is a: - liquid. - ANSWER- Which of the following statements would be considered good service practices for conserving refrigerant? - recover or recycle refrigerant; keep systems tight; find and repair leaks - ANSWER- Under the EPA "safe disposal requirements", the person responsible for making sure that the refrigerant has been removed from household refrigerators before they are disposed of is the: - final person in the disposal chain - ANSWER- Which refrigerant listed below is a "low-pressure refrigerant" under EPA's refrigerant recycling regulations? - R- 123 - ANSWER- When moisture exists in an operating system, which of the following is the most likely to occur? - Acid will form - ANSWER- Which of the following is a "very high-pressure refrigerant" under EPA's refrigerant recycling regulations?

• R- 13 - ANSWER- When using nitrogen to pressurize a system, you should: - only charge with nitrogen vapor. - ANSWER- Of the refrigerants listed below, which has the lowest ozone depletion potential? - R-134a - ANSWER- When dealing with small systems, how many different refrigerants may be recovered into the same cylinder? - ONLY ONE - ANSWER- When operating refrigerant recovery or recycling equipment, the following precautions should always be followed - wear safety glasses; wear protective gloves; follow all safety precautions for the equipment - ANSWER- Of the refrigerants listed below, which types of refrigerants will not damage stratospheric ozone? - HFCs - ANSWER-

When evacuating a system, the hoses should b: - as short in length and as large in diameter as possible. - ANSWER- Refrigerant leaves the condenser of an operating system as a: - high pressure liquid. - ANSWER- If corrosion is found within the body of a relief valve, the valve must be: - replaced. - ANSWER- The Clean Air Act: - sets a schedule for the phase out of CFC/HCFC production; prohibits venting of refrigerants; authorizes the EPA to set standards for recover of refrigerants. - ANSWER- Measuring the system's final vacuum is always done with: - the system isolated and the vacuum pump off. - ANSWER- A refillable refrigerant cylinder must never be filled to more than_________ of its capacity by weight: - 80% - ANSWER- Of the refrigerants listed below, which refrigerant type have the highest ozone depletion potential? - CFCs - ANSWER- This chemical was found in the upper stratosphere and that indicates that the ozone layer is being destroyed. - chlorine monoxide - ANSWER- What factor(s) affects the speed of evacuation? - the size of the equipment being evacuated; the ambient temperature; the amount of moisture in the system - ANSWER- HCFC refrigerants contain: - hydrogen, chlorine, fluorine, carbon - ANSWER- When a system will not hold vacuum after is has been evacuated, then: - they system may be leaking. - ANSWER- All recovery equipment currently being made is required to have: - an EPA approved certification label. - ANSWER-

The color code for approved refrigerant recovery cylinders is______. - yellow tops and gray bodies - ANSWER- When can you use a disposable cylinder to recover refrigerant? - never - ANSWER- Which of the following is a "high-pressure refrigerant" under EPA's refrigerant recycling regulations? - R22 - ANSWER- After refrigerant liquid transfer between recovery unit and the system being emptied, you need to avoid trapping: - liquid refrigerant between service valves. - ANSWER- You can determine safe pressure for leak testing a system from the: - low-side test-pressure data-plate value. - ANSWER- If a technician has a system where some R-502 was added to an R-22 system. The technician should: - recover all the refrigerant into a separate tank. - ANSWER- Ozone in the stratosphere above the earth consists of: - molecules of 3 oxygen atoms. - ANSWER- The size (capacity) of the vacuum pump and the size of the suction line used will determine: - the length of dehydration time. - ANSWER- According to the EPA, when dealing with customer complaints regarding additional costs due to refrigerant recovery efforts, the technician should: - explain the refrigerant recovery is necessary to protect human health and the environment; explain that refrigerant recovery is required by the Federal(and in some cases state and local)laws; inform the customer that professional service personnel are duty bound to follow the law and to protect the environment - ANSWER- State and local governments can make state laws that: - follow the Clean Air Act/EPA regulations; contain stricter regulations than the Clean Air Act/EPA regulations. - ANSWER- If an oil is hygroscopic it means that it: - readily absorbs moisture. - ANSWER-

When dehydrating a system, the system can be heated to: - decrease the dehydration time. - ANSWER- The synthetic lubricant presently used with ternary blends containing HCFCs is: - alkylbenzene - ANSWER- Ozone depletion in the stratosphere is what type of problem? - GLOBAL - ANSWER- On a typical three port (three hose) manifold gauge, the center port is used for: - recovery, evacuation and charging. - ANSWER- Ester based oils can be mixed with: - no other oils. - ANSWER- CFCs will no longer be manufactured or imported into the United States after: - 1995 - ANSWER- Which type of refrigerants are chlorine-free? - HFCs - ANSWER- Refrigerant recovery during low ambient temperatures will: - slow the recovery process. - ANSWER- _______ 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 any way. - Recovering - ANSWER- Containers designated "refillable" by DOT are used for transporting recovered pressurized refrigerant________. - to meet safety requirements - ANSWER-