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EPA 608 Core
Practice core knowledge questions (test may include content from Types 1/2/3)
| Question | Answer |
|---|---|
| R-410A has global warming potential (GWP) how much greater compared to R-744? | correct answer: thousands of times greater (bottom of page 6 in packet) incorrect options: |
| Global warming potential of R-600a and R-441A are ______ when compared to the GWPs of R-134a, R-407C, R-404A, and R-410A. | correct answer: significantly lower (bottom of page 6 in packet) incorrect options: |
| It is best practice to use dry nitrogen to break vacuum when dehydrating by triple evacuation method. However, it: | correct answer: requires pressure regulator (top of page 13 in packet) incorrect options: often contains moisture, requires minimum of 10psig, is toxic when released into atmosphere |
| Approved refrigerant recovery cylinders can be identified by which color code? | correct answer: yellow tops and gray bodies (top of page 14 in packet) incorrect options: gray tops and yellow bodies, blue tops and green bodies, green tops and gray bodies |
| Which type of synthetic oils are commonly used in new HFC systems and for retrofitting HCFC equipment to HFC refrigerants? | correct answer: polyolester (POE) (bottom of page 8 in packet) incorrect options: glycol, alkylbenzene, mineral oil |
| When using nitrogen in repairing sealed refrigeration system, what should nitrogen tank always be equipped with? | correct answer: (pressure) regulator (top of page 13 in packet) incorrect options: float sensor, red top, hand valve |
| Which of following factors affect speed of system dehydration? | correct answer: ambient temperature and amount of moisture in system (bottom of page 12 in packet) incorrect options: ambient temperature and entropy of refrigerant, latent heat content of refrigerant, system superheat |
| When pungent odor is detected during sealed system recovery and/or repair, which of following is most likely? | correct answer: compressor burnout has occurred (top of page 18 in packet) incorrect options: refrigerant should not be recovered, it is characteristic smell of refrigerant, refrigerant should be vented |
| Which of following best describes low loss fittings on refrigerant recovery devices used to recover CFCs, HCFCs, and HFCs? | correct: can be either manually/automatically closed when disconnected to prevent loss of refrigerant from hoses (top of pg. 5) incorrect: leak only small amounts of refrig. during use, must be discarded after each use, eliminate oil loss during recovery |
| What is state of refrigerant leaving (liquid) receiver in refrigeration system? | correct answer: high pressure liquid incorrect options: low pressure liquid, low pressure vapor, high pressure vapor |
| In which component of system does refrigerant change from high pressure vapor to high pressure liquid? | correct answer: condenser (middle of page 3 in packet) incorrect options: receiver, metering device, accumulator |
| How should refrigerant cylinders be positioned when they are shipped? | correct answer: upright (bottom of page 14 in packet) incorrect options: inverted, horizontally, stacked |
| Why are some hydrofluoroolefin (HFO) refrigerants classified as A2L? | correct answer: they are less flammable than hydrocarbon refrigerants, but most are still mildly flammable (middle of page 7 in packet) incorrect options: they have toxicity characteristics, are prohibited for use in USA, have high ODPs and low GWPs |
| Which of following gases is used as baseline measurement for global warming potential (GWP)? | correct answer: carbon dioxide (bottom of page 6 in packet) incorrect options: ammonia, CFC-12, propane |
| Very large refrigerant leak can cause suffocation because refrigerants: | correct answer: are heavier than air and displace oxygen (middle of page 18 in packet) incorrect options: smell strong and make breathing difficult, are lighter than air and cause dizziness, sting nose and cause sneezing |
| When evacuating system, use of severely oversized vacuum pump could: | correct answer: cause trapped water to freeze (bottom of page 25 in packet) incorrect options: cause trapped oil to freeze, cause trapped refrigerant to freeze, cause valves to freeze |
| What are two factors that, if present, are most likely to lead to explosion with hydrocarbon (HC) refrigerants? | correct answer: sufficient concentration of refrigerant in space and ignition source (middle of page 13 in packet) incorrect options: electrical wiring and water, leak from system and airflow, direct sunlight and warm temperatures |
| After recovering refrigerant from sealed system if nitrogen is used to pressurize or blow debris out of system, nitrogen: | correct answer: may be vented to ambient air (middle of page 18 in packet) incorrect options: must be recovered, should be returned to cylinder, should only be used if mixed with R-22 |
| Which of following are recommended safe work practices when recovering refrigerants? | correct answer: wear safety eyewear/butyl-lined gloves when connecting/disconnecting hoses (middle of page 18) incorrect options: wear respirator when working with any refrigerant, wear cotton gloves when working with any compressed gas, no PPE required |
| What effect will low ambient temperatures have on recovery? | correct answer: increase recovery time incorrect options: shorten recovery time, minimize emissions, require frequent drier changes |
| Which of following is true if system will not hold vacuum after it has been evacuated? | correct answer: system may be leaking incorrect options: system is ready to be charged, system has been adequately evacuated, expansion valve is clogged |
| How would you remove moisture from refrigerant in system? | correct answer: use filter drier incorrect options: purge condenser, drain oil separator, reduce water flow to condenser |
| Which of following statements about "self-contained" recovery devices is true? | correct: remove refrig. from appliance without assistance of appliance components incorrect: evacuated cylinders capable of liquid transfer, have self-contained power source requiring periodic charging, can only be used on equipment with <15 lbs. refrig. |
| Which leak repair category does 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? | correct answer: comfort cooling incorrect options: commercial refrigeration, industrial process refrigeration, ice making refrigeration |
| What does ozone depletion potential (ODP) measure? | correct answer: ability of substance to destroy ozone in stratosphere incorrect options: ability of substance to cause global warming, rating of health hazards caused by ozone depletion, length of time refrigerant stays in atmosphere |
| Which of following refrigerant releases is considered violation of EPA prohibition on venting? | correct: release of mixture of nitrogen & refrig. resulting from adding nitrogen to fully charged appliance to leak check incorrect: de minimis releases in good faith, emitted during normal appliance operation, emitted when dis/connecting low loss hoses |
| What is service procedure if refrigerant in recovery cylinder is suspected to be contaminated? | correct answer: take pressure reading of cylinder incorrect options: weigh cylinder, discard refrigerant, dilute refrigerant with virgin refrigerant |
| Before beginning refrigerant recovery procedure, it is always necessary to: | correct answer: know type of refrigerant that is in system incorrect options: allow appliance to stabilize at room temperature, remove appliance to outdoor location, disconnect appliance from its power source |
| What is best use for testing with soap bubbles? | correct answer: to pinpoint refrigerant leaks incorrect options: to find refrigerant leaks in coil fin area, to detect leaks in water tube condensers, to detect leaks if condenser is excessively dirty |
| What is component directly following condenser in refrigeration system using thermal expansion valve (TXV)? | correct answer: (liquid) receiver incorrect options: compressor, accumulator, evaporator |
| What is term for removing refrigerant in any condition from system and storing it in external container without necessarily testing or processing it in any way? | correct answer: recovery incorrect options: recycling, reclaiming, restoring |
| Which type of refrigerant has highest ozone depletion potential (ODP)? | correct answer: CFCs incorrect options: HCFCs, HFCs, HFOs |
| When HFC system with POE oil has been opened for major system repair, what is minimum evacuation level that should be achieved before charging system? | correct answer: 500 microns incorrect options: 20 inches Hg, 10 inches of mercury, 25 inches Hg |
| What is state of refrigerant entering compressor of refrigeration system? | correct answer: low pressure vapor incorrect options: high pressure liquid, high pressure vapor, low pressure liquid |
| In what state should system be to measure final system vacuum? | correct answer: with system isolated and vacuum pump turned off incorrect options: with gas ballast open, with vacuum pump operating, with system heated |
| What must be done before disposing of any appliance containing CFC, HCFC, or HFC refrigerant? | correct answer: recover refrigerant incorrect options: purge appliance with nitrogen, flush appliance with R-134a, seal appliance so no refrigerant can escape |
| When corrosion is found within body of relief valve, valve must be: | correct answer: replaced incorrect options: repaired, reconditioned, cleaned |
| What is Montreal Protocol? | correct answer: international treaty that addresses ozone depleting substances and their alternatives incorrect options: test for energy efficiency adopted by Canadian gov., procedure for measuring CFC levels in atmosphere, test for ozone concentration |
| Which ASHRAE classification means slightly flammable? | correct answer: A2L incorrect options: A1, A3, B1 |
| What is Significant New Alternative Policy (SNAP) Program? | correct answer: EPA's program that identifies refrigerants with lower overall risks to human health/environment incorrect options: covers only CFCs/HCFCs used in residential A/C, relates to CFCs/HCFCs used in commercial A/C, covers only CFCs/HCFCs in IPR |
| HFCs: | correct answer: will not damage stratospheric ozone but have high GWP incorrect options: will damage stratospheric ozone and have low GWP, will not deplete stratospheric ozone and have low GWP, are only harmful to ground level ozone |
| Which international agreement regulated production and use of CFCs, HCFCs, halons, methyl chloroform, and carbon tetrachloride? | correct answer: Montreal Protocol incorrect options: Kyoto Treaty, Council of Nicaea, Treaty of Ghent |
| Which of following refrigerants is an HFO? | correct answer: R-1234ze (found on top of P/T chart) incorrect options: R-22, R-134a, R-410A |
| Which of following refrigerants has GWP of 1? | correct answer: carbon dioxide (labeled as R-744 on top of P/T chart) incorrect options: R-22, R-134a, R-410A |
| Which of following has highest ozone depletion potential? | correct answer: CFCs incorrect options: HFOs, HCFCs, HFCs |
| How much can person be fined per day per violation for knowingly releasing regulated substance that violates Clean Air Act? | correct answer: $44,539 incorrect options: $10,000, $25,000, $37,000 |
| Low side test pressure data plate value should be used by technician to determine safe pressure for: | correct answer: leak testing incorrect options: recovering refrigerant, refrigerant charging, retrofitting system |
| Clean refrigerant for reuse by separating oil from refrigerant and removing moisture from refrigerant by passing it through one or more filter driers is definition of: | correct answer: recycle incorrect options: recover, reclaim, reuse |
| Chlorine in CFCs and HCFCs: | correct answer: will not dissolve in water incorrect options: will dissolve in water, will rain out of atmosphere, is heavier than air and cannot rise to stratosphere |
| Recover any remaining refrigerant and then render cylinder useless, then recycle metal is proper disposal method for: | correct answer: disposable cylinders incorrect options: recovery cylinders, one pound cans, accumulator cylinders |
| Molecule found in CFCs and HCFCs that depletes ozone is: | correct answer: chlorine incorrect options: fluorine, hydrogen, carbon |
| Single chlorine atom can destroy how many ozone molecules? | correct answer: 100,000 incorrect options: 100, 1,000, 10,000 |
| Silicone elastomers, for use in seals and gaskets, are not compatible with which refrigerants? | correct answer: HFOs incorrect options: HCFCs, CFCs, HFCs |
| Reusable refrigerant containers under high pressure must be hydrostatically tested how often? | correct answer: 5 years incorrect options: 1 year, 3 years, 7 years |
| HCFCs contain: | correct answer: hydrogen, chlorine, fluorine, and carbon incorrect options: chlorine/fluorine/carbon, hydrogen/fluorine/carbon, hydrogen/fluorine/olefin |
| Why is chlorine in CFCs and HCFCs refrigerants more likely to reach stratosphere to destroy ozone layer than other compounds with chlorine? | correct answer: chlorine in refrigerants does not dissolve in water or rain out of/break down in lower atmosphere incorrect options: |
| To process refrigerant to level equal to new (virgin) product specifications as determined by chemical analysis defines: | correct answer: reclaiming incorrect options: recovery, reuse, recycling |
| Crop loss, eye disease, and skin cancer have been attributed to: | correct answer: depletion of stratospheric ozone incorrect options: depletion of stratospheric nitrogen, depletion of stratospheric chlorine monoxide, depletion of stratospheric oxygen |
| Before shipping any used refrigerant cylinders, check that cylinder meets what standards? | correct answer: Department of Transportation (DOT) incorrect options: Significant New Alternatives Policy (SNAP), Underwriters Laboratories (UL), all of above |
| Compressor: | correct answer: changes low pressure vapor to high pressure vapor incorrect options: changes high pressure vapor to high pressure liquid, changes high pressure liquid to low pressure liquid, changes low pressure liquid to low pressure vapor |
| Condenser: | correct answer: changes high pressure vapor to high pressure liquid incorrect options: changes low pressure vapor to low pressure liquid, changes high pressure liquid to low pressure liquid, changes low pressure liquid to low pressure vapor |
| Refrigerant cylinder designed to hold recovered refrigerant has: | correct answer: gray body and yellow top incorrect options: yellow body and gray top, green body and yellow top, orange body and gray top |
| Ozone molecule contains: | correct answer: three oxygen atoms incorrect options: one oxygen atom, two oxygen atoms, four oxygen atoms |
| Which type of refrigerant contains no chlorine? | correct answer: HFCs incorrect options: HCFCs, HCFC blends, CFCs |
| Refrigeration technicians who violate Clean Air Act can: | correct answer: all of above (lose their EPA certification, be fined, be required to appear in federal court) |
| After 1995, any supplies of CFC refrigerant to service existing units in United States can only come from: | correct answer: recovery and recycling incorrect options: solvent conversion, European chemical manufacturers, Third World chemical manufacturers |
| Refrigerant that is recovered can be returned to: | correct answer: same system or other systems owned by same person without restriction incorrect options: used in any system serviced that day, sold as used refrigerant to other customers, called reclaimed if filter-drier was used during recovery |
| Refrigerant cannot be called "reclaimed" unless it: | correct answer: has been chemically analyzed and refrigerant meets ARI-700 purity standard incorrect options: was processed in reclaiming machine, is recovered from system less than 1 year old, is recovered from system still under warranty |
| EPA can require technician to demonstrate their ability to perform proper procedures for recovering and/or recycling refrigerant. Failure to demonstrate competency can result in: | correct answer: revocation of technician's certification incorrect options: seizure of technician's recovery/recycling equipment, seizure of any refrigerant purchased by technician still in their possession, mandatory attendance at refrigerant training |
| What characteristics of CFCs make them more likely to reach stratosphere than most other compounds containing chlorine (Cl)? [they are not attracted to static/dust in atmosphere or lighter than other damaging compounds] | correct answer: refrigerants containing Cl but not hydrogen are so stable they do not break down in lower atmosphere after being released, Cl (or bromine) reacts with ozone causing it to change back to oxygen thus destroying ozone layer |
| System is considered dehydrated when: | correct answer: vacuum indicator shows you have reached and held required finished vacuum incorrect options: vacuum pump has run at least 7 hours, manifold suction gauge has held 30 inches Hg/760 mm vacuum for 3 hours, you are ready to leave for day |
| Disposable refrigerant containers are used for what type of refrigerant? | correct answer: virgin incorrect options: recycled, recovered, both recycled and recovered |
| Which refrigerant is HCFC? | correct answer: R-124 (found on top of P/T chart) incorrect options: R-134a, R-410A, R-12 |
| What statement is true about azeotropic refrigerant mixtures? | correct answer: mixture that acts like single component refrigerant over its entire range incorrect options: always made from just 2 components, has P/T curve identical to one of its components, mixture always made from at least 3 component refrigerants |
| Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) have which of following in common? | correct answer: must be recovered before opening or disposing of appliances incorrect options: have identical ODPs, both contain hydrogen, have same normal boiling points |
| To scrap disposable cylinder, internal cylinder pressure should be reduced to at least: | correct answer: 0psig incorrect options: 15psig, 20psig, 28.8psig |
| Manifold gauge sets are often color coded, when this is done, high pressure gauge is color coded: | correct answer: red incorrect options: white, blue, yellow |
| In general, blended refrigerants should be charged: | correct answer: as liquid incorrect options: as vapor, at very high temperatures, same as any other refrigerant |
| Blended refrigerants leak from system: | correct answer: in uneven amounts due to different vapor pressures incorrect options: faster than other refrigerants, slower than other refrigerants, only if joint fails completely |
| Which of following gases help form earth's protective shield? | correct answer: stratospheric ozone incorrect options: chlorine, chlorides, carbon monoxide |
| In refrigeration system, device that changes low pressure vapor to high pressure vapor is: | correct answer: compressor incorrect options: evaporator, expansion device, condenser |
| Data shows that chlorine (Cl) in stratosphere comes mainly from CFCs rather than from natural sources such as volcanoes because: | correct: all of above (strat. Cl rise matches CFC emissions rise & amount of fluorine which has different natural sources than Cl as well as strat. air samples taken over erupting volcanoes show they contribute small amount of strat. Cl compared to CFCs) |
| Which atom of CFC molecule causes ozone depletion? | correct answer: chlorine incorrect options: fluorine, sodium, helium |
| Ozone layer protects earth from: | correct answer: ultraviolet radiation from sun incorrect options: nuclear radiation, infrared radiation, bacteria from space |
| When using any solvent, cleaner, chemical, or refrigerant, you should review: | correct answer: material safety data sheets incorrect options: moisture solubility information, chemical compound reference sheets, chemical composition reference sheets |
| Award of up to what amount may be paid to person supplying information that leads to penalty against technician who is intentionally venting? | correct answer: $10,000 incorrect options: $5,000, $27,000, $37,000 |
| Montreal Protocol is: | correct answer: treaty among nations that controls production of CFCs and HCFCs incorrect options: test for energy efficiency developed by Canadian gov., procedure for measuring chlorine levels in stratosphere, test for ozone concentration in atmosphere |
| What is one of most serious results from damage to ozone layer? | correct answer: increases in human skin cancer incorrect options: mutations of marine plants, increased volcanic activity, higher natural background radioactivity |
| Of refrigerants listed below, which has lowest ozone depletion potential? | correct answer: R-22 incorrect options: R-11. R-12, R-113 |
| To determine maximum allowable pressure to use when checking system, check: | correct answer: design pressure on equipment nameplate incorrect options: with equipment owner, with refrigerant pressure/temperature tables, ask local utility company |
| Ozone depletion potential (ODP) is: | correct answer: measure of ability of CFCs and HCFCs to destroy ozone incorrect options: always equal to twice global warming potential or GWP, absolute rating of health hazard caused by ozone depletion, rating for ground level smog pollution |
| Example of HFC refrigerant is: | correct answer: R-134a (found on top of P/T chart) incorrect options: R-12, R-22, R-123 |
| Whenever dry nitrogen from portable cylinder is connected to system, what item is of most importance in consideration of safety? | correct answer: relief valve in downstream line from pressure regulator incorrect options: regulator has new set of gauges, pressure gauges are clean, no refrigerant lines can leak |
| During service of refrigeration system containing regulated refrigerant, refrigerant must be: | correct answer: recovered incorrect options: recovered and replaced with R-134a no exceptions, vented, destroyed |
| Which safety precautions should always be followed? | correct answer: all of above (never apply open flame to refrigerant cylinder, never cut or weld any refrigerant line when refrigerant is in line, never use oxygen to purge lines or to pressurize system) |
| In vapor compression refrigeration system, cooling occurs when: | correct answer: refrigerant liquid turns to vapor (in evaporator on low side of system) incorrect options: refrigerant vapor turns into liquid, refrigerant is under maximum pressure, refrigerant gives off heat |
| Evacuation of system is method of: | correct answer: dehydration incorrect options: pinpointing location of leaks, acid removal, all of above |
| Each chlorine atom in stratosphere can destroy how many ozone molecules? | correct answer: 100,000 incorrect options: 100, 1,000, 10,000 |
| Example of HFC refrigerant: | correct answer: R-410A (found on top of P/T chart) incorrect options: R-11, R-22, R-124 |
| Which gas would cause least damage to environment during leak check? | correct answer: dry nitrogen incorrect options: dry nitrogen and R-22, dry nitrogen and R-12, compressed air and R-12 |
| Refrigerant migrates to compressor crankcase because of difference in what between refrigerant and oil? | correct answer: vapor pressure incorrect options: acidity, volume, density |
| It is important not to mix refrigerants in same container because: | correct answer: mixture may be impossible to reclaim incorrect options: mixture will explode, mixture is corrosive, they use different oils |
| When using recovery unit, fill level of recovery tank can be controlled by: | correct answer: all of above (mechanical float switch, electronic shutoff device, and weight) |
| Which of following human health effects could result from increase in ultraviolet radiation? | correct answer: increase in cataracts cases incorrect options: increase in male infertility cases, increase in heat prostration with elderly, increase in number of thyroid disorders |
| Never use open flame to heat refrigerant tank because: | correct answer: all of above (can result in venting refrigerant to atmosphere, tank may explode causing serious injury to people nearby, and refrigerant in tank may decompose forming toxic material) |
| When transporting cylinders containing used refrigerant, DOT (Department of Transportation) requires that you: | correct answer: attach DOT classification tags incorrect options: use OSHA approved containers, ship by EPA certified carrier, do all of above |
| According to ASHRAE's 1992 refrigeration safety classification, which of following designations would be most safe? | correct answer: A-1 incorrect options: A-3, B-1, B-3 |
| Over-evacuation of system: | correct answer: does not occur incorrect options: causes vacuum pump damage, damages vacuum gauge sets, can cause tube, condenser, and/or evaporator collapse |
| Equipment covered by EPA regulations include: | correct options: all A/C and refrigeration equipment using CFCs, HCFCs, or HFCs incorrect options: only refrigerators/freezers using CFCs, only A/C and refrigeration equipment containing HCFCs, only commercial A/C and refrigeration equipment made in USA |
| Never overfill refrigerant storage cylinder because: | correct answer: internal pressure of cylinders may rise in heated areas and cause explosion incorrect options: cylinder may be too heavy to carry, some refrigerant may be vented as cylinder valve is closed, extra space might be needed for next job |
| Manifold gauge sets are often color coded, when this is done, low pressure (compound) gauge is color coded: | correct answer: blue incorrect options: red, white, yellow |
| All devices used for refrigerant recovery must: | correct answer: meet EPA standards incorrect options: be portable and weigh less than 100 pounds, contain heavy duty ozone shield, have 5 ton refrigeration rating at 100 degrees F |
| Reusable refrigerant containers that are normally under any pressure above 15psig must be hydrostatically tested and date stamped every: | correct answer: 5 years incorrect options: 1 year, 2 years, 3 years |
| Which refrigerants must be recovered before opening or disposing of system? | correct answer: all refrigerants must be recovered incorrect options: R-134a, R-407C, R-410A |
| To obtain accurate vacuum readings during system evacuation, system vacuum gauge should be located: | correct answer: as far from vacuum pump as possible incorrect options: at pump discharge, directly at pump suction, anywhere in evacuation service hose |
| What is best proof that CFCs are in stratosphere? | correct answer: measurements of CFCs in air samples from stratosphere incorrect options: theory of some professors in California, measurements of CFCs in smog, measurement of other manmade compounds in air samples from stratosphere |
| Recovery of refrigerants is necessary for: | correct answer: all of above (adequate supplies for service after production bans as well as prevention of venting to the atmosphere and stratospheric ozone depletion) |
| Compound pressure gauge, typically used on low side of system, measures pressure in: | correct answer: psig and inches of mercury (vacuum) incorrect options: psia, torrs and microns, psia and microns |
| What refers to process of cleaning refrigerant by oil separation and single or multiple passes through filter driers, which reduce moisture and acidity? | correct answer: recycling incorrect options: recovering, reclaiming, restoring |
| High pressure gauge on service manifold sets has continuous scale, usually calibrated to read from: | correct answer: 0 to 500psig (or 0 to 800psig) incorrect options: 200 microns to 0psig, 0 to 250psig, 200 to 750psig |
| What is process that returns refrigerant to new product specifications and requires chemical analysis? | correct answer: reclaim incorrect options: recycle, recovery, reprocess |
| Cylinder with gray body and yellow top indicates that cylinder is designed to hold what? | correct answer: recovered refrigerant incorrect options: nitrogen, inert gas, only R-12 |
| HCFC refrigerants: | correct answer: are less harmful to stratospheric ozone than CFCs incorrect options: are more harmful to stratospheric ozone than CFCs, do not damage stratospheric ozone in any way, are more harmful than bromine containing compounds |
| Which type of refrigerant is most harmful to stratospheric ozone? | correct answer: refrigerants containing bromine incorrect options: refrigerants containing chlorine, refrigerants containing hydrogen, refrigerants containing fluorine |
| According to EPA, what type of leak detection method is considered to be most effective for locating general area of small leak? | correct answer: electronic or ultrasonic tester incorrect options: standard vacuum test, halide torch, audible sound |
| Long hoses between unit and recovery machine should not be used because they cause: | correct answer: all of above (excessive pressure drop as well as increased recovery time and emissions) |
| Recovery equipment that relies upon compressor in system would be considered: | correct answer: system-dependent incorrect options: self-contained, system independent, self-sufficient |
| Hermetic compressor must never be operated when: | correct answer: there is dehydration vacuum in system incorrect options: compressor is operating under light load, compressor is operating under full load, outdoor temperature is above 125 degrees F |
| Self-contained recovery devices: | correct answer: can capture liquid and/or vapor refrig. without assistance of equip. components incorrect options: are evacuated recov. cylinders capable of liquid transfer, have self-contained power source, can only be used on equip. containing <15 lbs. |
| Systems charged with medium or high pressure refrigerant should be leak checked with: | correct answer: pressurized nitrogen incorrect options: CFCs, HCFCs, compressed dry air |
| R-410A is not typical blended refrigerant because: | correct answer: all of above (near azeotropic refrigerant, can be charged as either liquid or vapor, and while it has 400 series refrigerant number it behaves like 500 series refrigerant) |
| Ternary refrigerant blend is how many part mixture? | correct answer: three part incorrect options: two part, four part, five part |
| In refrigeration system, high pressure vapor is converted to high pressure liquid in: | correct answer: condenser incorrect options: liquid receiver, TXV, suction line accumulator |
| Which of following is approved "drop-in" service replacement? | correct answer: according to EPA, there are no "drop-in" replacements incorrect options: HFC-134a, HFC-410A, R-407C |
| Proper method of discarding disposable refrigerant cylinder is to : | correct answer: assure that all refrigerant is recover and that cylinder is rendered useless then recycle metal incorrect options: bleed refrig. to ambient and throw into dumpster, refill again at approved facility, use as compressed air tank |
| CFC refrigerants are so named because they contain what elements? | correct answer: chlorine, fluorine, and carbon incorrect options: chlorine/fluorine/calcium, carbon/fluorine/calcium, chlorine/fluorine/hydrogen |
| What does compressor do in refrigeration cycle? | correct answer: compress and pressurize refrigerant incorrect options: reject heat, absorb heat, reduce pressure and temperature of refrigerant |
| What does metering device do in refrigeration cycle? | correct answer: reduce pressure and temperature of refrigerant incorrect options: compress and pressurize refrigerant, reject heat, absorb heat |
| Class 2 refrigerants are: | correct answer: mildly flammable incorrect options: not flammable, highly flammable, very toxic |
| Which class of refrigerants are more toxic? | correct answer: Class B incorrect options: Class A, Class 1, Class 2 |
| Why are manufacturers moving to HFO refrigerants? | correct answer: both low ozone depletion potential and global warming potential incorrect options: low ozone depletion potential, low global warming potential, no flammability |
| HFC refrigerants lack which element? | correct answer: chlorine incorrect options: hydrogen, fluorine, carbon |
| Which safety classification are both R-22 and R-410A? | correct answer: A-1 (found on top of P/T chart) incorrect options: A2L, A3, B1 |
| What characteristic of R-404A, R-407C, R-422D, and R-422B may lead to them not being used in the future? | correct answer: high global warming potential (found on top of P/T chart) incorrect options: low ozone depletion potential, low flammability, low toxicity |
| What safety classification are R-404A, R-407C, R-422D, and R-422B? | correct answer: A-1 (found on top of P/T chart) incorrect options: A2L, A3, B1 |
| Which characteristics do R-441A and R-600a share? | correct answer: all of above (HC refrigerants, low global warming potential, and A3 safety classification) |
| Before you dispose of any system containing refrigerant, you must: | correct answer: recover refrigerant incorrect options: purge system with nitrogen, flush system with R-11 or R-113, seal system so no refrigerant can escape during disposal |
| According to EPA regulations, which of following procedures is not approved technique for system cleanup after burnout? | correct answer: flushing with liquid refrigerant to clean tubing incorrect options: installing suction line filter drier, triple evacuation, deep vacuum evacuation |
| When using nitrogen to pressurize system, you should always: | correct answer: charge through pressure regulator incorrect options: charge nitrogen as liquid, pressurize to above 1000psi, never use nitrogen inside system |
| What effects can ozone depletion have on environment? | correct answer: all of above (reduced crop yields and marine life as well as increased ground level ozone) |
| Non-azeotropic refrigerants leak from system: | correct answer: in uneven amounts due to different vapor pressures incorrect options: faster than other refrigerants, slower than other refrigerants, only if joint fails completely |
| Example of HCFC refrigerant is: | correct answer: R-22 (found on top of P/T chart) incorrect options: R-12, R-134a, R-410A |
| Which chemicals are controlled by Montreal Protocol? | correct answer: all of above (chlorofluorocarbons, hydrochlorofluorocarbons, and halons) |
| When evacuating system, hoses should be: | correct answer: equal to or larger than vacuum pump inlet connection incorrect options: orange in color for safety reasons, as long as possible, smaller than vacuum pump inlet connection |
| Never use oxygen or compressed air to pressurize system because: | correct answer: when mixed with compressor oil or some refrigerants, it could explode incorrect options: leaks are more difficult to detect, pressures produced are not as good, they do not mix with refrigerants |
| Refrigerant cylinders should always be: | correct answer: all of above (free of rust and damage, color coded to indicate contents, and secure) |
| Even though R-22 is considered nontoxic, it: | correct answer: can cause asphyxia incorrect options: is lighter than air, is Class I refrigerant, can be detected by its color |
| System is dehydrated to: | correct answer: remove water and water vapor incorrect options: remove oil and oil vapor, remove refrigerant and refrigerant vapor, none of above |
| According to EPA, which types of refrigerants listed below will not contribute to global warming? | correct answer: they all contribute to global warming incorrect options: CFCs, HCFCs, HFCs |
| Type of oil that is most commonly used in stationary air conditioning applications with HFC-410A refrigerant is: | correct answer: (polyol)ester oil (POE) incorrect options: alkylbenzene oil, mineral oil, all oils are compatible with HFC-410A |
| Technicians receiving passing grade on Type II (medium, high and very high pressure) exam are certified to recover refrigerant during maintenance, service, or repair equipment using medium, high, and very high pressure refrigerants, including: | correct answer: with Type II certification, you are certified for all very high pressure refrigerants including R-744, CFC-13, and CFC-503 incorrect options: R-744, CFC-13, CFC-503 |
| Personal protective equipment (gloves, safety glasses, safety shoes, etc.) should always be worn when: | correct answer: handling and filling refrigerant cylinders incorrect options: reporting for work, climbing ladders, lifting |
| Refrigerant vapors or mist should not be inhaled because: | correct answer: they may cause heart irregularities and/or unconsciousness incorrect options: they are addictive, they can lower body's core temperature, they may cause skin cancer |
| Of items listed below, which are violations of Clean Air Act? | correct answer: all of above (falsifying/failing to keep required records, failing to reach required evacuation levels before opening/disposing of appliances, knowingly releasing CFC/HCFC refrigerants or their substitutes while repairing appliances) |
| HFC refrigerants contain: | correct answer: hydrogen, fluorine, carbon incorrect options: helium/fluorine/carbon, helium/fluorine/calcium, hydrogen/fluorine/chlorine |
| Recovery equipment that relies upon pressure of refrigerant in appliance would be considered: | correct answer: system-dependent incorrect options: self-contained, illegal, self-sufficient |
| Refrigerant that enters compressor under normal operating conditions is: | correct answer: low pressure vapor incorrect options: low pressure liquid, high pressure liquid, high pressure vapor |
| It is necessary to place refrigerant label on: | correct answer: refrigerant cylinder which is being returned for reclaiming incorrect options: cylinder to identify pressure, truck to identify cylinder hauler, cylinder to identify gross weight |
| Which refrigerant is CFC? | correct answer: R-12 (found on top of P/T chart) incorrect options: R-123, R-134a, R-410A |
| Use what to remove ice from sight glass? | correct answer: alcohol spray incorrect options: water, R-11 refrigerant, screwdriver or flat file |
| According to EPA, oil sample should be taken for which of following reasons? | correct answer: system had leak or major component failure incorrect options: new filter drier has been installed, system is not cooling properly, recycled refrigerant was added to system |
| EPA requires installation of service aperture or process stub on all appliances using regulated substances as refrigerant. Main purpose of this requirement is to make it easier to: | correct answer: recover refrigerant incorrect options: change compressor lubrication, vent non-condensables, dehydrate system |
| Recycling and recovery equipment intended for use with air conditioning and refrigeration equipment (except for small appliances) must be tested under: | correct answer: ARI 740 incorrect options: ARI 700, EPA 700, UL 740 |
| Refrigerant entering compressor of refrigeration system is: | correct answer: superheated vapor incorrect options: liquid, subcooled liquid, subcooled vapor |
| Type of oil that is most commonly used in stationary refrigeration applications with HFC-134a refrigerant is: | correct answer: (polyol)ester oil (POE) incorrect options: alkylbenzene oil, mineral oil, all oils are compatible with HFC-134a |
| Term used to describe fact that refrigerant blend has range of boiling or condensing points at constant pressure is: | correct answer: temperature glide incorrect options: pressure slide, mixture slump, fractionation |
| Under EPA's regulations, what standard must reclaimed refrigerant meet before it can be resold? | correct answer: ARI 700 incorrect options: ARI 740, EPA 700, UL 740 |
| It is illegal to: | correct answer: knowingly release any regulated refrigerant during service, maintenance, repair, or disposal of appliances, with exception of de minimis releases incorrect options: use CFCs, manufacture or import HFCs, do any of above |
| Refrigerant that enters expansion or throttling device (also known as metering device) is: | correct answer: liquid incorrect options: saturated vapor, superheated vapor, mixture of vapor and liquid |
| Which of following statements would be considered good service practices for conserving refrigerant? | correct answer: all of above (recover or recycle refrigerant, keep systems tight, find and repair leaks) |
| Under EPA "safe disposal requirements", person responsible for making sure that refrigerant has been removed from household refrigerators before they are disposed of is: | correct answer: final person in disposal chain incorrect options: service technician last worked on equipment, manager of service company that last serviced equipment, EPA field inspectors |
| Which refrigerant listed below is low pressure refrigerant under EPA's refrigerant recycling regulations? | correct answer: R-123 (found on top of P/T chart) incorrect options: R-22, R-124, R-134a |
| When moisture exists in operating system, which of following is most likely to occur? | correct answer: acid will form (middle of page 12 in packet) incorrect options: copper tubes and fittings will rust, compressor discharge valves will freeze up, compressor head pressures will rise |
| Which of following is very high pressure refrigerant under EPA's refrigerant recycling regulations? | correct answer: R-744 (found on top of P/T chart) incorrect options: R-22, R-134a, R-600a |
| When using nitrogen to pressurize system, you should: | correct answer: only charge with nitrogen vapor incorrect options: never use pressure regulator, never use pressure relief valve, always charge to at least 1000psig |
| When dealing with small systems, how many different refrigerants may be recovered into same cylinder? | correct answer: only one incorrect options: only two, any number as long as all are CFCs, depends on reclaim company |
| When operating refrigerant recovery or recycling equipment, following precautions should always be followed: | correct answer: all of above (wear safety glasses and protective gloves as well as follow all safety precautions for equipment) |
| Of refrigerants listed below, which types of refrigerants will not damage stratospheric ozone? | correct answer: HFCs (middle of page 7 in packet) incorrect options: CFCs, HCFCs, they all damage ozone |
| Refrigerant leaves condenser of operating system as: | correct answer: high pressure liquid (middle of page 3 in packet) incorrect options: low pressure liquid, low pressure vapor, high pressure vapor |
| If corrosion is found within body of relief valve, valve must be: | correct answer: replaced incorrect options: repaired, reconditioned, cleaned |
| Clean Air Act: | correct answer: all of above (sets schedule for phaseout of CFC/HCFC production, prohibits venting of refrigerants, and authorizes EPA to set standards for recovery of refrigerants) |
| Measuring system's final vacuum is always done with: | correct answer: system isolated and vacuum pump off (bottom of page 12 in packet) incorrect options: gas ballast wide open, vacuum pump operating, system being heated |
| Refillable refrigerant cylinder must never be filled to more than what percentage of its capacity by weight? | correct answer: 80% (top of page 14 in packet) incorrect options: 70%, 90%, 95% |
| Of refrigerants listed below, which refrigerant type has highest ozone depletion potential? | correct answer: CFCs (top of page 7 in packet) incorrect options: HCFCs, HFCs, all are equal |
| This chemical was found in upper stratosphere and that indicates that ozone layer is being destroyed: | correct answer: chlorine monoxide (middle of page 6 in packet) incorrect options: carbon monoxide, carbon dioxide, nitrogen dioxide |
| What factors affect speed of evacuation? | correct answer: all of above (size of equipment being evacuated, ambient temperature, and amount of moisture in system) (bottom of page 12 in packet) |
| HCFC refrigerants contain: | correct answer: hydrogen, chlorine, fluorine, and carbon (middle of page 7 in packet) incorrect options: helium/chlorine/fluorine/carbon, helium/chlorine/fluorine/calcium, hydrogen/chlorine/fluorine/calcium |
| When system will not hold vacuum after it has been evacuated, then: | correct answer: system may be leaking (bottom of page 12 in packet) incorrect options: system is ready to be charged, system has been adequately evacuated, expansion valve is clogged |
| All recovery equipment currently being made is required to have: | correct answer: EPA approved certification label (middle of page 11 in packet) incorrect options: calibration stamp or label, oil-less reciprocating compressors, manual triple shutoffs |
| When can you use disposable cylinder to recover refrigerant? | correct answer: never (middle of page 14 in packet) incorrect options: when system contains same refrigerant as cylinder and cylinder is less than year old, when system contains less than 2 pounds of refrigerant, only in emergency to avoid venting |
| Which of following refrigerants is high pressure refrigerant under EPA's refrigerant recycling regulations? | correct answer: R-22 (found on top of P/T chart) incorrect options: R-12, R-134a, R-600a |
| After refrigerant liquid transfer between recovery unit and system being emptied, you need to avoid trapping: | correct answer: liquid refrigerant between service valves (bottom of page 11 in packet) incorrect options: oil in transfer unit receiver, oil in refrigeration system's cooler, liquid refrigerant in recovery receiver |
| You can determine safe pressure for leak testing system from: | correct answer: low side test pressure data plate value (middle of page 13 in packet) incorrect options: discharge operating pressure, ambient +30 degrees temperature/pressure value, ambient at standby condition |
| If technician has system where some refrigerants were mixed, technician should: | correct answer: recover all refrigerant into separate tank (bottom of page 11 in packet) incorrect options: vent all refrigerant, recycle all refrigerant, recover and reuse all refrigerant in another system |
| Ozone in stratosphere above earth consists of: | correct answer: molecules of 3 oxygen atoms (middle of page 6 in packet) incorrect options: molecules of 1 oxygen atom, molecules of 2 oxygen atoms, molecules of 4 oxygen atoms |
| Size (capacity) of vacuum pump and size of suction line used will determine: | correct answer: length of dehydration time (bottom of page 12 in packet) incorrect options: where vacuum hose is connected to system, type of refrigerant that should be used, viscosity of oil that should be used |
| According to EPA, when dealing with customer complaints regarding additional costs due to refrigerant recovery efforts, technician should: | correct: all of above (explain recovery is necessary to protect human health/environment as well as required by federal plus some state/local laws, and inform customer that professional service personnel must follow laws to not risk their certification) |
| State and local governments can make laws that: | correct answer: both follow Clean Air Act/EPA regulations and contain stricter regulations than CAA/EPA (middle of page 9 in packet) incorrect option: ease or reduce federal CAA/EPA regulations |
| If oil is hygroscopic, it means that it: | correct answer: readily absorbs moisture (bottom of page 8 in packet) incorrect options: is good lubricant, is unrefined mineral oil, can be left open to ambient air without picking up moisture |
| When dehydrating system, system can be heated to: | correct answer: decrease dehydration time (bottom of page 12 in packet) incorrect options: avoid oxidation, increase oil's viscosity, increase dehydration time |
| Synthetic lubricant presently used with ternary blends containing HCFCs is: | correct answer: alkylbenzene (AB) (bottom of page 8 in packet) incorrect options: mineral oil, esters, natural oil |
| Ozone depletion in stratosphere is what type of problem? | correct answer: global (top of page 6 in packet) incorrect options: American, Third World, continental |
| On typical three port/hose manifold gauge, center port is used for: | correct answer: recovery, evacuation, and charging (top of page 5 in packet) incorrect options: obtaining gauge readings, pumping air into system, bypass from low to high side |
| Ester based oils can be mixed with: | correct answer: no other oils (bottom of page 8 in packet) incorrect options: paraffinic mineral oils only, alkylbenzene oils only, mineral oils |
| Which type of refrigerants are chlorine free? | correct answer: HFCs (middle of page 7 in packet) incorrect options: CFCs, HCFCs, both CFCs and HCFCs |
| Refrigerant recovery during low ambient temperatures will: | correct answer: slow recovery process (bottom of page 11 in packet) incorrect options: shorten recovery time since recovery tank is cold, minimize harmful emissions, require more frequent drier changes |
| What is process of removing refrigerant in any condition from system and storing it in external container without necessarily testing or processing it in any way? | correct answer: recovering (top of page 11 in packet) incorrect options: recycling, reclaiming, restoring |
| Containers designated refillable by DOT are used for transporting recovered pressurized refrigerant: | correct answer: to meet safety requirements incorrect options: so refrigerants can be mixed, to prevent overfilling, none of above |
| Which refrigerant is HCFC? | correct answer: R-123 (found on top of P/T chart) incorrect options: R-12, R-134a, R-410A |
| Which class of refrigerant is most harmful to stratospheric ozone? | correct answer: CFCs (top of page 7 in packet) incorrect options: HCFCs, HFCs, ammonia |
| Of refrigerants listed below, which has lowest ozone depletion potential? | correct answer: R-134a (labeled as HFC on top of P/T chart, which have no ODP vs higher ODPs of refrigerants containing chloring like CFCs and HCFCs) incorrect options: R-12, R-22, R-123 |
| When evacuating system, hoses should be: | correct answer: as short in length and large in diameter as possible (bottom of page 12 in packet) incorrect options: suitably sized to connect to gauge manifold, coiled and taped together, colored red or blue to meet codes |
| What is being done in United States to stop damage to stratospheric ozone layer? | correct answer: capturing, recycling, and ultimately eliminating use of refrigerants containing chlorine (CFCs and HCFCs) incorrect options: replacing coal fired power plants, enforcing strict emission requirements on garbage incinerators, all of above |
| Tapping compressor with rubber mallet will aid in doing what? | correct answer: releasing trapped refrigerant from (compressor) oil (bottom of page 12 in packet) incorrect options: releasing trapped water in compressor oil, releasing trapped acids in compressor oil, releasing trapped nitrogen in compressor oil |
| Which exams does technician need to pass in order to obtain Universal Certification? | correct answer: Core, Type I, Type II, and Type III incorrect options: Type I, Type II, Type III |
| Technician with Type III certification can repair what type of appliances? | correct answer: low pressure appliances such as chillers incorrect options: medium and high pressure appliances such as heat pumps, small appliances such as window AC units and domestic refrigerators, motor vehicle AC units |
| Technician with Type II certification can repair what type of appliances? | correct answer: medium and high pressure appliances such as heat pumps incorrect options: low pressure appliances such as chillers, small appliances such as window AC units and domestic refrigerators, motor vehicle AC units |
| Can you work under someone else's certification? | correct answer: no, you need your own incorrect options: yes, sometimes, in emergency |
| Technician with Type I certification can repair what type of appliances? | correct answer: small appliances such as window AC units and domestic refrigerators incorrect options: medium and high pressure appliances such as heat pumps, low pressure appliances such as chillers, motor vehicle AC units |
| What two points in refrigeration system divides low and high pressure sides? | correct answer: compressor and metering device incorrect options: evaporator and condenser, receiver and accumulator, liquid line and suction line |
| What state does refrigerant enter compressor as? | correct answer: low pressure, low temperature superheated vapor incorrect options: subcooled liquid, subcooled vapor, saturated |
| Blue gauge on gauge manifold set is: | correct answer: low pressure compound gauge incorrect options: high pressure gauge, vacuum gauge, evacuation gauge |
| Where in refrigeration cycle is pressure reduced, causing small percentage of refrigerant to flash to vapor (flash gas)? | correct answer: metering device incorrect options: compressor, condenser, evaporator |
| What is de-minimis release of refrigerant? | correct answer: minor release of refrigerant such as removing hoses with low loss fittings after service or repair incorrect options: large leak of refrigerant, any release of refrigerant to atmosphere, any illegal venting of refrigerant |
| Center port and hose of gauge manifold is used for which of following? | correct answer: all of above (recovery, evacuation, and charging) |
| ODP stands for Ozone Depletion Potential which measures substance's ability to: | correct answer: destroy ozone molecules in stratosphere incorrect options: cause global warming, contaminate atmosphere, enter groundwater |
| Purpose of stratospheric ozone layer is to protect earth from: | correct answer: sun's ultraviolet radiation incorrect options: nuclear radiation, infrared radiation, bacteria from space |
| What element in refrigerants causes ozone depletion? | correct answer: chlorine incorrect options: fluorine, carbon, hydrogen |
| Ozone molecule is made up of: | correct answer: 3 oxygen atoms incorrect options: 1 oxygen atom, 2 oxygen atoms, 4 oxygen atoms |
| When chlorine atom takes one of ozone molecule's oxygen atoms, what compound is formed? | correct answer: chlorine monoxide incorrect options: carbon monoxide, carbon dioxide, hydrochloric acid |
| What type of refrigerant is R-12? | correct answer: CFC incorrect options: HCFC, HFC, HFO |
| What elements do CFCs contain? | correct answer: chlorine, fluorine, and carbon incorrect options: calcium/fluorine/carbon, chlorine/fluorine/calcium, chlorine/fluorine/hydrogen |
| Which type of refrigerant has highest ODP? | correct answer: CFCs incorrect options: HCFCs, HFCs, HFOs |
| Which refrigerant is example of HFC? | correct answer: R-134a incorrect options: R-12, R-22, R-1234yf |
| Which refrigerants do not contain chlorine and have zero ODP? | correct answer: all of above (HFCs, HCs, and HFOs) |
| What is maximum fine penalty for violating Clean Air Act? | correct answer: $44,539 per day per violation incorrect options: $10,000, $20,000, $30,000 |
| What international agreement addresses protection of stratospheric ozone by phasing out production of ozone-depleting substances? | correct answer: Montreal Protocol incorrect options: Kyoto Protocol, Toronto Treaty, Tokyo Treaty |
| Which of following constitutes violation of Section 608 of Clean Air Act? | correct answer: knowingly releasing or venting ozone depleting substances and substitute refrigerants incorrect options: de minimis releases in good faith, emitted during normal appliance operation, emitted when dis/connecting low loss hoses |
| What year will all HCFCs be phased out by? | correct answer: 2030 incorrect options: 2040, 2050, 2060 |
| What was first group of refrigerants to get phased out under Montreal Protocol? | correct answer: CFCs incorrect options: HCFCs, HFCs, HFOs |
| What is purpose of Significant New Alternatives Policy (SNAP) program? | correct answer: to identify, evaluate, and approve substitute refrigerants incorrect options: covers only CFCs/HCFCs used in residential A/C, relates to CFCs/HCFCs used in commercial A/C, covers only CFCs/HCFCs in IPR |
| If substance has not been approved by SNAP program, can it be used to retrofit existing system? | correct answer: no incorrect options: sometimes, yes, in emergency |
| CFCs and HCFCs can be: | correct answer: used to service system that contains those refrigerants incorrect options: used in any system, cannot be used anymore, used to top off any system |
| Which of following is good "drop-in" replacement? | correct answer: there are no 'drop-in' replacements incorrect options: R-12, R-22, R-410A |
| What type of oil found in HFCs and HFOs cannot be mixed with oils in older systems? | correct answer: polyolester (POE) oils incorrect options: alkylbenzene oil, mineral oil, any kind of oil |
| What type of oil does an HCFC-based blend use? | correct answer: alkylbenzene (AB) oil incorrect options: mineral oil, polyolester (POE) oil, any kind of oil |
| HFC refrigerant blends use: | correct answer: polyolester (POE) oil incorrect options: alkylbenzene oil, mineral oil, any kind of oil |
| Which type of refrigerant blend acts like single refrigerant with no temperature glide or fractionation? | correct answer: azeotropic blends incorrect options: zeotropic blends, HCFC blends, HFC blends |
| When is bubble point used? | correct answer: when charging by condenser subcooling method incorrect options: when charging by suction or evaporator superheat method, when charging with vapor refrigerant, when charging with saturated refrigerant |
| When is dew point used? | correct answer: when charging by suction or evaporator superheat method incorrect options: when charging by condenser subcooling method, when charging with liquid refrigerant, when charging with saturated refrigerant |
| What does fractionation mean? | correct answer: individual refrigerants in blend may leak at different rates incorrect options: fraction of refrigerant that must be vapor when charging, fraction of refrigerant that must be liquid when charging, fraction of temperature glide |
| Refrigerants that evaporate and condense at range of temperatures at given pressure is definition of: | correct answer: temperature glide incorrect options: fractionation, dew point, bubble point |
| When converting low side pressure to evaporator temperature, with R-400 series blend refrigerant, technician should use which pressure value on temperature-pressure chart? | correct answer: dew point incorrect options: bubble point, temperature glide, fractionation |
| After determining general area of leak, what can be used to pinpoint it? | correct answer: soap bubbles incorrect options: halide torch, eletronic leak detector, ultrasonic leak detector |
| What is most effective way to determine general area of leak? | correct answer: use electronic or ultrasonic leak detector incorrect options: soap bubble solution, halide torch, fluorescent dye leak detection |
| What is first issue technician can look for when inspecting refrigeration system known to be leaking? | correct answer: traces of oil around fittings incorrect options: traces of water around fittings, pungent odor, there are no visible signs |
| Which process is defined as removing refrigerant (in any condition) and storing it in external container to be put back in same system? | correct answer: recover incorrect options: recycle, reclaim, reuse |
| Which process is defined as cleaning refrigerant by oil separation and passing it through one or more filter-driers? | correct answer: recycle incorrect options: recover, reclaim, reuse |
| Which process involves chemical analysis to determine if refrigerant is back to new product specifications? | correct answer: reclaim incorrect options: recover, recycle, reuse |
| Which recovery device uses active recovery unit to draw refrigerant from appliance? | correct answer: self-contained incorrect options: system-dependent, self-sufficient, passive |
| Which recovery device uses passive recovery unit to draw refrigerant from appliance? | correct answer: system-dependent incorrect options: self-contained, self-sufficient, active |
| Can all recovered refrigerants be mixed into same container? | correct answer: no, each refrigerant needs its own container incorrect options: yes, sometimes, in emergency |
| Recovery efficiency will be dependent on which of following? | correct answer: all of above (ambient temperature, size of appliance, and amount of moisture in system) |
| What will using long hoses during recovery process result in? | correct answer: all of above (increased pressure drop, recovery time, and emissions) |
| Recovered refrigerant that is contaminated must be recovered into: | correct answer: separate tank incorrect options: same tank as virgin refrigerant, same tank as uncontaminated recovered refrigerant, disposable tank |
| What is purpose of evacuation and dehydration? | correct answer: to remove non-condensables (air) and water vapor incorrect options: to remove oil and oil vapor, to remove refrigerant vapor, to remove toxic gases |
| Final system vacuum measurement should be done with: | correct answer: vacuum pump turned off incorrect options: vacuum pump still running, no micron gauge attached, vacuum pump disconnected from system |
| What can form if water or water vapor is left in system? | correct answer: hydrochloric and hydrofluoric acid incorrect options: ozone, chlorine monoxide, carbon monoxide |
| How many microns should system be evacuated to? | correct answer: 500 microns or lower incorrect options: 800 microns or lower, 700 microns or lower, 600 microns or lower |
| What factors have impact on evacuation speed and efficiency? | correct answer: all of above (ambient temperature, amount of moisture in system, size of piping and coils, and size of pump and pump intake pipe) |
| Recovery cylinder should never be filled more than what percentage of its capacity by weight? | correct answer: 80% incorrect options: 70%, 90%, 95% |
| Overfilling recovery cylinder may result in: | correct answer: explosion incorrect options: cylinder leaking, fire, cylinder becoming warm |
| How often does reusable container for refrigerant need to be hydrostatically tested? | correct answer: every 5 years incorrect options: every 6 months, every year, every other year |
| What does approved refrigerant recovery cylinder look like? | correct answer: has yellow top and gray body incorrect options: has gray top and yellow body, has yellow top and green body, has gray top and green body |
| How should refrigerant cylinders be transported? | correct answer: in upright position with DOT classification tag incorrect options: stacked on side, upside down, loose in back of van |
| What protective equipment should technician wear when filling refrigerant cylinders or using recovery equipment? | correct answer: safety glasses and protective gloves incorrect options: wear respirator when working with any refrigerant, wear cotton gloves when working with any compressed gas, no PPE required |
| When checking for leak, what should technician use to pressurize system? | correct answer: nitrogen incorrect options: oxygen, compressed air, acetylene |
| How should pressure relief valve be installed on nitrogen line, when using more than one? | correct answer: only parallel, never in series with each other incorrect options: only series/never in parallel with each other, both series and parallel, either series or parallel |
| When should technician use pressure regulator and relief valve? | correct answer: when using nitrogen to check for leaks in system incorrect options: when brazing or soldering, when using disposable cylinder for compressed air, when using recovery cylinder for multiple refrigerants |
| What can refrigerants cause if inhaled in high concentrations? | correct answer: all of above (unconsciousness, heart irregularities, suffocation/asphyxia, and death) |
| In event of large release of refrigerant into confined space, why should technicians (and everyone else) immediately vacate and ventilate area? | correct answer: because refrigerant will displace oxygen, causing suffocation incorrect options: because it will explode, because it will ignite, there is no reason |
| In event of large release of refrigerant into confined space, what personal protective equipment (PPE) is required? | correct answer: self-contained breathing apparatus (SCBA) incorrect options: filtering respirator, safety glasses and gloves, proper footwear |
| When adding refrigerant into undercharged system: | correct answer: liquid refrigerant is throttled into low side with system operating incorrect options: liquid refrigerant is throttled into high side, vapor refrigerant is throttled into low side, vapor refrigerant is throttled into high side |
| Due to flammability of some HCs and HFOs: | correct answer: equipment must be designed to handle those refrigerants incorrect options: they cannot be mixed, they can be used as fuel, they can be used to braze or solder |
| EPA regulates maximum amount of refrigerant that can be used in new HC and HFO systems by their: | correct answer: type and use incorrect options: manufacture date, weight, height |
| EPA lists refrigerants in four liquid-phase pressure ranges at 104°F condensing temperature to: | correct answer: better define leak rates and service recovery levels incorrect options: correspond to different sections of EPA 608 exam, make refrigerants easier to identify, there is no reason behind it |
| Hygroscopic oils will: | correct answer: absorb moisture out of air and even through some containers incorrect options: is good lubricant, is unrefined mineral oil, can be left open to ambient air without picking up moisture |
| Distributors that sell HCFC, HFC, or another regulated refrigerant must verify: | correct answer: purchaser is or employs Section 608 certified technician incorrect options: buyer is over 18, buyer is over 21, buyer is over 25 |
| Section 608 of Clean Air Act sets forth rules and regulations for: | correct answer: refrigerant handling in HVACR industry incorrect options: power plant emissions, motor vehicle emissions, emissions from hazardous materials |
| Never inhale refrigerant vapors or mist in high concentrations because: | correct answer: they may cause heart irregularities or unconsciousness (middle of page 13 in packet) incorrect options: they are addictive, they can lower body's core temperature, they may cause skin cancer |
| Which of following is considered to be good service practice? | correct answer: all of above (repair leaks whenever possible, recover and recycle refrigerant, and determine type of refrigerant in system before recovery) |
| Proper method of charging blended refrigerant is in: | correct answer: liquid phase incorrect options: vapor phase, both vapor and liquid, saturated state |
| Failure of system to hold vacuum concluding evacuation process indicates that: | correct answer: leak in system may exist incorrect options: system is ready to be charged, system has been adequately evacuated, orifice tube is plugged |
| When operating recovery or recycling equipment, you should: | correct answer: all of above (wear safety glasses and protective gloves along with follow all safety precautions for equipment) |
| Definition of reclaim: | correct answer: process refrigerant to level equal to new product specifications as determined by chemical analysis |
| Definition of recycle: | correct answer: clean refrigerant for reuse by oil separation and passes through moisture absorption device |
| Definition of recover: | correct answer: remove refrigerant in any condition, from system, and store it in external container |
| Never expose CFC-12 to open flame because they may form: | correct answer: all of above (hydrochloric and hydrofluoric acids plus phosgene gas) |
| Lubricant used with HFC-134a is: | correct answer: POE (ester) oil incorrect options: mineral oil, alkylbenzene oil, whale oil |
| All devices used to recover/recycle refrigerant must: | correct answer: meet EPA standards incorrect options: be portable, contain heavy duty pump, all of above |
| Which of following refrigerants has lowest GWP? | correct answer: R-744 (carbon dioxide) incorrect options: R-134a, R-410A, R-600a |
| Only accurate method of charging is to: | correct answer: weigh refrigerant into system incorrect options: charge until sight glass is clear, charge until gauge pressures are correct, charge as vapor with compressor running |
| Depletion of ozone layer causes: | correct answer: all of above (skin cancer, eye disease, and crop loss) |
| Refillable cylinders used to transport recovered refrigerants: | correct answer: all of above (must be DOT approved, properly labeled and tagged, along with hydrostatically tested every 5 years) |
| Recovery cylinders must not be filled above 80% of their capacity and safe filling capacity can be controlled by: | correct answer: any of above (mechanical float devices, electronic shut-off, or weight (scales)) |
| Refrigerant must not be vented because: | correct answer: all of above (it is illegal and expensive as well as depletes the ozone layer) |
| When disposing of empty or near empty disposable cylinder, you should: | correct answer: all of above (attach cylinder to recovery unit, reduce cylinder to vacuum, and mark cylinder empty) |
| Before charging system with recycled refrigerant, refrigerant should be checked for: | correct answer: non-condensables incorrect options: phosgene gas, acids, chlorine monoxide |
| Section 608 of Federal Clean Air Act requires that all persons handling and servicing systems using refrigerants must: | correct answer: all of above (use EPA approved equipment, be certified in recovery procedures, and never intentionally vent refrigerant) |
| It is important not to mix different refrigerants in same container because: | correct answer: mixture may be impossible to reclaim incorrect options: mixture will explode, refrigerant mixture might be toxic, it violates EPA regulations |
| Which of following repairs would always be considered major under EPA regulations? | correct answer: replacement of evaporator coil incorrect options: replacement of filter drier, replacement of Schrader valve core, replacement of condenser fan motor |
| What should be used to remove ice from sight or viewing glasses? | correct answer: alcohol spray incorrect answers: refrigerant, water, screwdriver or flat file |
| Which of following safety precautions should be adhered to for low pressure systems? | correct answer: use gloves/safety goggles when working with liquid refrigerant incorrect options: reset water freezestat after recharging, shut down compressor before removing gauge from low side, use leak detector before entering mechanical room |
| Systems charged with R-134a should be leak checked with: | correct answer: pressurized nitrogen incorrect options: CFCs, HCFCs, compressed dry air |
| CFCs will no longer be manufactured or imported after: | correct answer: 1995 incorrect options: 1994, 1996, 1997 |
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