Download HVAC Core Exam: Questions and Answers for Certification and more Exams Engineering in PDF only on Docsity!
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Where is the stratosphere located? - correct answer ✅Between 7 and 30 miles above sea level What is the ozone layer? - correct answer ✅The Earth's security blanket What does an ozone molecule consist of? - correct answer ✅3 oxygen atoms What do oxygen atoms do? - correct answer ✅Protect us from harmful ultraviolet radiation from the sun, and helps maintain stable Earth temperatures What does CFC contain? - correct answer ✅chlorine, fluorine, and carbon What does HCFC contain? - correct answer ✅Hydrogen, chlorine, fluorine, and carbon
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What does CFC and HCFC both have in common? - correct answer ✅They both contain chlorine A single chlorine atom can destroy how many ozone molecules? - correct answer ✅100, Which adds more chlorine to the atmosphere: A: An erupting volcano B: Chlorine-containing refrigerants - correct answer ✅B: Chlorine-containing refrigerants The rise in the amount of chlorine measured in the stratosphere over the past twenty years matches the rise in... - correct answer ✅CFC and HCFC emissions What does HFC contain? - correct answer ✅Hydrogen, Fluorine, and Carbon
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What does HFC and HFO have in common? - correct answer ✅They both do NOT contain chlorine What is the ODP of HFCs and HFOs? - correct answer ✅ 0 How do greenhouse gases warm the Earth? - correct answer ✅1. by absorbing energy, slowing the rate at which it escapes
- by acting like a blanket insulating the Earth What is Carbon Dioxide (CO2)? - correct answer ✅A natural gas, created through respiration and absorbed through photosynthesis Carbon Dioxide is created and absorbed through a relatively balanced cycle? (True/False) - correct answer ✅True What are equipments with flammable refrigerants required to have? -
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correct answer ✅A red color marking on all process tubes, service connections, and pipes through which a flammable refrigerant passes How long must the red color marking (on all processing tubes) for flammable refrigerants be? - correct answer ✅One inch in both directions from service locations What are two examples of "A3" flammable refrigerants that do NOT require recovery? - correct answer ✅Propane and Isobutane When propane is used as a refrigerant, it does not have to meet the purity standards set for HVACR equipment. (True/False) - correct answer ✅False, it does need to met the purity standards What are 3 examples of fluorinated gases? - correct answer ✅CFCs, HCFCs, HFCs
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R-410A has a GWP _________ times greater than carbon dioxide A: 29 B: 290 C: 2090 D: 20900 - correct answer ✅C: 2090 What is R-410A? - correct answer ✅A high pressured HFC refrigerant with an ODP of zero and global warming potential (GWP) 2090 times greater than carbon dioxide R-134a has a GWP _________ times greater than carbon dioxide A: 14300
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B: 1430
C: 143
D: 14.3 -
correct answer ✅B: 1430 R-410A is near _______________ that does not fractionate during phase change in HVACR equipment
correct answer ✅azeotrope refrigerant R-410A is near azeotrope refrigerant that fractionates during phase change in HVACR equipment (True/False)
correct answer ✅False, it does NOT fractionate during phase change in HVACR equipment What is R-1234yf? - correct answer ✅A medium pressure, HFO refrigerant with an ODP of 0 and global warming pressure (GWP) only 4 times greater than carbon dioxide
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B: 1990
C: 1991
D: 1992 -
correct answer ✅B: 1990 What happens if you violate Clean Air Act provisions? - correct answer ✅You may lose your certification, be required to appear in Federal Court, and be fined up to $44,539 per day, per violation. It is the responsibility of the _______ person in the disposal chain to ensure that refrigerant has been removed from appliances before scrapping A: First B: Final C: First and Final - correct answer ✅B: Final
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Technicians disposing of mid-sized applianced with 5- 50 pounds of refrigerant must keep records of: - correct answer ✅- The location, date of recovery, and type of refrigerant recovered for each disposed appliance
- The quantity of refrigerant, by type, recovered from disposed applianced in each calendar month
- The quantity of refrigerant, and type, transferred for reclamation or destruction, the person/company to whom it was transferred, and the date of transfer What is the Montreal Protocol of 1987 - correct answer ✅An international agreement (treaty) regulating the production and use of CFCs. HCFCs, halons, methyl chloroform, and carbon tetrachloride entered into force in mid 1989 What did the Montreal Protocol call for? - correct answer ✅Stepwise reduction and eventual
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D: 2050 -
correct answer ✅B: 2030 What are the Three Rs - correct answer ✅Recover, Recycle, Reclaim Refrigerant recovery and/or recycling equipment manufactured after November 15, 1993 must be certified and labeled by an EPA approved equipment testing organization to meet EPA standards (True/False) - correct answer ✅True What are the two basic types of recovery devices? - correct answer ✅1. "System-dependent"
- "Self contained" System-dependent is (passive/active) and Self contained is (passive/active) - correct answer ✅passive, active CFCs and HCFCs can not be used for servicing a system that uses the refrigerant after the phaseout;
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CFCs and HCFCs can be used in new equipment - correct answer ✅False, They CAN be used for servicing a system that uses refrigerant after the phaseout and can NOT be used in new equipment What does the Significant New Alternatives Policy program (SNAP) do? - correct answer ✅it identifies and evaluates substitute refrigerants When retrofitting HCFC systems, _________ type oil is commonly used as it can tolerate a small percentage of other types of oil - correct answer ✅polyoster Most refrigerant oils are hygroscopic. Hygroscopic oil has a (high/low) affinity for water - correct answer ✅high Refrigerant blends are made up of ______ single component refrigerants - correct answer ✅2 or more
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- one must be preformed after the appliance returns to normal operating cycle What are the three categories from section 608 of the Clean Air Act defines applicable leak rates for systems other than small appliances? - correct answer ✅Industrial Process Refrigeration (IPR), Commercial Refrigeration, Comfort Cooling What is the reason for dehydrating a refrigeration system? - correct answer ✅To remove water and water vapor and its important to follow proper dehydration procedures What will form if moisture is allowed to remain in an operating refrigeration system? - correct answer ✅Hydrochloric and hydrofluoric acids What is the suggested method of dehydration? - correct answer ✅Evacuation of a system
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Most manufacturers require evacuation to 500 microns or lower. This can be measured with a... - correct answer ✅Micron Guage You should never evacuate a system to the ambient air without first following proper recovery procedures and attaining the mandated recovery level (true/false)
correct answer ✅True What are the factors that can affect the speed and efficiency of evacuation? - correct answer ✅Size of equipment being evacuated, ambient temperature, amount of moisture in the system, the size of the vacuum pump and suction line A system that will not hold a vacuum probably does not have a leak. (True/False) - correct answer ✅False, it probably has a leak During evacuation you may wish to heat the refrigeration system to decrease hydration time. (True/False) - correct answer ✅True
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Recovery cylinders are specifically designed to be refilled (True/False) - correct answer ✅True, be careful to not overfill or heat the cylinders, it could cause an explosion EPA requires that a refillable refrigerant cylinder must NOT be filled above ____ percent of its capacity weight A: 50 B: 60 C: 70 D: 80 - correct answer ✅D: 80% Refillable cylinders must be hydrostatically tested and date stamped every _____________ A: 5 years
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B: 10 years C: 3 years D: 7 years - correct answer ✅A: 5 years Contrary to belief, Refillable cylinders do not have to be approved by the Department of Transportation (t/f)
correct answer ✅False, they DO need to be approved by the DOT Approved refrigerant recovery cylinders can be identified by which colors? - correct answer ✅Yellow top and grey bodies What should you do/wear when handling and filing refrigerant cylinders OR operating recovery or recycling equipment? - correct answer ✅Safety glasses, protective gloves, and follow all equipment manufacturers safety procedures
