EPA 608 Universal Certificate Exam| Complete Solutions |Verified Questions & Answers |100% Correct Solutions| Latest 2026–2027 Edition

EPA 608 Universal Certificate Exam| Complete Solutions |Verified Questions & Answers |100% Correct Solutions| Latest 2026–2027 Edition Q: As environmental technicians, we must be up to date with which type of laws? Answer Federal, State, and Local Laws Q: For EPA 608 Universal Certification, how many questions will you receive? Answer 100 Q: If you need to get type III certification, what will be on your exam? Answer 50 questions, 25 core and 25 type III questions. Q: What is the passing grade for all EPA certifications? Answer 70% Q: Once you Pass the EPA exam, the regulations you learn will never change. Answer False Q: Do natural events like volcanic eruptions contribute to chlorine in the stratosphere? Answer Yes, but are not the primary source Q: True or False: Ground level ozone is what absorbs and reflects harmful UV rays from the sun. Answer False Q: In which of the following ways does ozone depletion affect humans? Answer Increased risk of skin cancer and cataracts Q: Is there evidence that refrigerants are in the stratosphere? Answer YES Q: Which of the following statements is TRUE about chlorine? Answer A single chlorine atom can survive in the atmosphere for years. Q: Ozone has __ atoms of oxygen. Answer 3 Q: The majority of ozone is located in the Troposphere. t or f? Answer False Q: How many molecules of ozone can three molecules of chlorine destroy? Answer 300,000 (100,000 per chlorine molecule) Q: What is the major function of ozone in the stratosphere? Answer Absorb and reflect UV rays from the sun. Q: What is the primary source of chlorine in the stratosphere? Answer Emissions of refrigerant chemicals such as CFCs and HCFCs by humans. Q: What molecule destroys the ozone layer? Answer Chlorine Q: Which of the following an effects of ozone depletion? Answer Decreasing crop yields Q: Which refrigerant chemicals are responsible for the destruction of the ozone layer? Answer CFCs and HCFCs Q: Who does ozone depletion affect? Answer people all over the world Q: After refrigerant is phased out, can a technician still service the equipment containing that refrigerant? Answer YES Q: After being phased out, where can technicians obtain refrigerant to service equipment that contains that refrigerant? Answer From recovered and reclaimed refrigerant. Q: Can refrigerant be resold? Answer Yes, but only if it has been reclaimed to AHRI Standard 700 specifications Q: Equipment has to be certified to epa standards in order to recover which refrigerants Answer CFCs, HCFCs, HFCs Q: If you are selling R-22 refrigerant, who can you sell to? Answer A technician with Section 608 certification and a business that employs a technician with Section 608 certification. Q: If you recover R-12 refrigerant, can you use the recovered refrigerant in another device owned by a different person? Answer Yes, but only if it has been reclaimed to AHRI Standard 700 specifications. Q: In the United States, when were all CFCs phased out by? Answer 1995 Q: In the United States, when were R-22 and R-142b phased out? Answer 2020 Q: In the United States, when will all HCFCs be phased out? Answer 2030 Q: Which of the following records must be kept for an R-22? A. Type of refrigerant B. Dates C. Quantity of refrigerant D. Model of appliance Answer Type of refrigerant, dates, and Quantity Q: Section 608 of the Clean Air Act is: Answer federal law Q: State and Local Regulations ____ (select all that apply) A. Have to be followed in addition to federal CAA regulations B. Have to be followed instead of federal CAA regulations C. May be stricter than federal CAA regulations D. Are a suggestion Answer A. And C. The Venting Prohibition requires that you recover affected refrigerant before (Select all that apply): A. Opening equipment B. Servicing equipment C. Disposing of equipment D. Manufacturing equipment Answer Opening equipment, servicing equipment, disposing equipment Under Section 608 Regulations, who is responsible for ensuring that all refrigerant is removed before disposing of equipment that contains it? Answer The final person in the disposal chain. What appliances do Section 608 regulations apply to? Freezers Desiccant dehumidifiers Both None Answer Freezers What does SNAP stand for? Answer Significant New Alternatives Policy What is the fine for violating the Clean Air Act (as of 2017)? Answer $44,539 per day per violation What is the Montreal Protocol? Answer An international agreement between 197 countries What is the purpose of Section 608? (Select all that apply) Answer A. To protect the ozone layer B. To regulate use of chemicals that deplete ozone C. To raise money through fines D. Economic reasons Answer A and B What is the purpose of SNAP? (Select all that apply) Answer A. To evaluate alternative refrigerants B. To further the goals of the CAA C. To consider effects of substitute refrigerants on humans D. To consider effects of substitute refrigerants on the environment Answer All of them What do you do if you discover that you have added Refrigerant B to a system that contained Refrigerant A? Answer Consider that Refrigerant A is ozone-depleting. Recover the mixture in a separate recovery cylinder. What needs to be done before disposing of equipment that contains CFCs, HCFCs, or their substitutes? Recover the equipment What other appliances do Section 608 regulations apply to? A. Commercial refrigeration equipment B. Air conditioning equipment C. Both of the above D. None of the above C What penalties can technicians face if they violate the Clean Air Act? (Select all that apply) A. They may lose their Section 608certification B. They may face federal charges C. They may have to do community service D. They may be fined A, B, and D. Which of the following are considered de minimis releases of refrigerant? (Select all that apply) Answer A. HCFCs released when disconnecting hoses equipped with low loss fittings B. Release of carbon dioxide with low-loss fittings C. Release of HFCs due to catastrophic failure of equipment D. None of the above A and C Which of the following are excluded from Section 608 refrigerant management requirements? (Select all that apply) A. Carbon dioxide B. HFCS C. Water D. Nitrogen A, C, and D Which of the following are violations of the CAA Venting Prohibition? (Select all that apply) A. Release of refrigerants because appliances were not recovered B. Releasing isobutane while servicing equipment C. Releasing HFC refrigerant because of catastrophic equipment failure D. Refrigerants released when disconnecting on low-loss hoses to service an appliance A and D Which of the following are considered natural refrigerants? (Select all that apply) Answer A. R-290 B. R-600a C. R-744 D. R-11 R-290, R-600a, and R-744 Which of the following do you not need Section 608 certification to purchase? Answer A. Nitrogen B. HFCs C. CFCS D. HCFCS A. Nitrogen Which of the following is a CFC? (Choose all that apply) Answer A. R-11 B. R-12 C. R-20 D. R-22 R-11 and R-12 Which of the following is an HCFC? (Choose all that apply) Answer R-11 R-12 R-20 R-22 R-22 Which of the following refrigerants does the Venting Prohibition cover? Answer A. CFCs and HCFCs B. CFCs, HCFCs, and HFCs C. CFCs and natural refrigerants D. All natural refrigerants B. Which organization can test your recovery equipment used to service a system with R-12? Answer UL AHRI С. ЕРА D. Both (A) and (B) D Who does not need to maintain proper records of refrigerants? The EPA Which of the following are considered de minimis releases? (Select all that apply) Answer A. Catastrophic equipment failure B. Accidental release with timely repair of appliances C. Releases when connecting or disconnecting hoses without low loss fittings D. Releases when connecting or disconnecting hoses with low loss fittings A, B and D Equipment that uses nitrogen as a refrigerant is not subject to Section 608 requirements. True or False True What is the next component the refrigerant flows to after passing through the evaporator? Compressor As the temperature of a liquid increases, what phase does it turn into? (Assume constant pressure) Vapor Does the refrigerant change state in the compressor? No, it does not change state When pressure is increased on a liquid while keeping the temperature constant, what state can the substance change into? Solid The refrigerant absorbs heat from your indoor air in order to: (Select all that apply) A. Make your house hotter B. Change state from liquid to vapor C. Make your house cooler D. None of the above B. and C. Which component has the opposite function to the condenser? Evaporator What is the compressor's job? To increase the pressure What is the condenser's job? To cool the high pressure vapor What is the function of the metering device? To decrease pressure What is the state of the refrigerant when it enters the condenser? High pressure vapor When the refrigerant enters the metering device, what state is it in? High pressure liquid When refrigerant exits the metering device, what state is it in? Low pressure liquid When the refrigerant enters the compressor from the evaporator, what state is it in? Superheated vapor When the refrigerant enters the evaporator, what state is it in? Liquid When the refrigerant exits the evaporator, what state is it in? Vapor What is the state of the refrigerant when it exits the evaporator? Low pressure vapor Which of the following components are associated with the high-pressure side of the refrigeration system? (Select all that apply) A. Evaporator B. Compressor C. Condenser D. Metering Device B and C Which components change the refrigerant's pressure? (Select all that apply) Answer A. Evaporator B. Compressor C. Condenser D. Metering Device B and C Which of the following states has the highest temperature? (Assume constant pressure) liquid solid vapor water Vapor True or False: Boiling requires the addition of heat. True Condensation happens when a gas or vapor cools down and becomes liquid. T or F? True For the same substance, at the same temperature, the average speed of molecules in a vapor is the same as the average speed of molecules in a liquid. Select one: True False True If we decrease the pressure of a substance, its boiling point decreases. Select one: True False True In the condenser, the refrigerant changes state. Select one: True False True The boiling point is the temperature at which a substance changes from a liquid state to a vapor or gas state. Select one: True False True The boiling point of most refrigerants is 212 °F. T or F? False The vapor leaving the compressor is lower in pressure than vapor entering the compressor. Select one: True False False You are boiling a pot of water with the lid on. As the water heats up and starts to boil, you notice that drops of water form on the bottom of the pot lid. This is an example of condensation. Select one: True False True Your air conditioning works by adding cold air into your house. Select one: True False False B2 refrigerants are more dangerous than which of the following? (Select all that apply) Answer A. B1 В. ВЗ C. A1 D. A2 A, C, and D B2 refrigerants are safer than which one of the following? Answer A. B1 В. ВЗ C. A2 D. A3 B What does CFC stand for? Answer Chlorocarbons Chlorofluorocarbons Chlorofluorons Carbonfluoride Chlorofluorocarbons Which of the following elements do CFCs contain? (Select all that apply) Answer A. Cadmium B. Carbon C. Carbon dioxide D. Fluorine E. Chlorine B, D, and E What does HCFC stand for? Answer Hydrocarbons Hydrofluorocarbons Hydrochlorofluorocarbons Hydrochlorofluoros Hydrochlorofluorocarbons Other than fluorine and chlorine, what do HCFCs contain? (Select all that apply) Answer A. Hydrogen B. Carbon C. Helium D. Calcium A and B Which of the following molecules can be found in HCFCs? (Select all that apply) Answer A. Fluorine B. Chlorine C. Ceranium D. Halon A and B What does HFC stand for? Answer Hydrofluorocarbons Hydrochlorofluorocarbons Hydrocarbons Hydroflouridecarbons Hydrofluorocarbons Which of the following molecules can be found in HFCs? Answer Helium Hydrogen Halon Chlorine Hydrogen Other than hydrogen, which of the following molecules do HFCs contain? (Select all that apply) Answer A. Fluorine B. Carbon C. Cadmium D. Chlorine A and B What safety classification do HFO refrigerants typically fall under? Answer A. A2L B. A2 C. B2 D. B2L A2L What does HFO stand for? Answer Hydrofluorocarbons Hydrofluorooxygens Hydrocarbons Hydrofluoroolefins Hydrofluoroolefins Which of the following do HFOs contain? Answer A. Hydrogen B. Halon C. Chlorine D. Oxygen Hydrogen Which of the following do HFOs contain? (Select all that apply) Answer A. Fluorine B. Falon C. Oxygen D. Carbon A and D Which statement is true about hydrocarbons? Answer A. Are generally A3 refrigerants B. Have high toxicity C. Have low flammability D. Are safe to use because they are natural refrigerants A. If a refrigerant has an ODP of 0.05, which of the following are true? (Select all that apply) Answer A. It contains chlorine D. It might contain chlorine C. It could be R-22 D. It could be R-1234yf A and C Which one of the following refrigerants has the highest global warming potential (GWP)? Answer R-12 R-22 R-410a R-1234yf R-12 Which one of the following refrigerants has the lowest global warming potential (GWP)? Answer R-12 R-22 R-410a R-1234yf R-1234yf R-11 is the same as Answer CFC-11 HCFC-11 HFC-11 HFO-11 CFC-11 R-12 has a GWP in which of the following ranges? Answer A. 1-500 В. 500-1000 С. 1000-10,000 D. 10,000-50,000 D R-12 is the same as Answer CFC-12 CFC-11 HCFC-12 HFO-12 CFC-12 R-1234yf is the same as: Answer CFC-1234yf HCFC-1234yf HFC-1234yf HFO-1234yf HFO-1234yf R-134a is the same as Answer CFC-134a HCFC-134a HFC-134a HFO-134a HFC-134a R-410a has a GWP in which of the following ranges? Answer A. 1-500 В. 500-1000 С. 1000-10,000 D. 10,000-50,000 C. R-410a is the same as Answer CFC-410b HFC-410b HFC-410a HFO-410a HFC-410a The GWP of R-290 is greater than which of the following? (Select all that apply) Answer R-410a R-134a R-22 None of these None of these What is the main safety concern with R-410a? Answer None, it's an A1 refrigerant so there are nosafety concerns Toxicity Blood oxygenation Asphyxia Asphyxia What does the new subclass (2L) describe? Answer A. Alternate highly flammable refrigerants B. Refrigerants that are Class 2 and burn slowly C. Refrigerants that are Class 2 and take longer to be effective D. Refrigerants that are toxic B What is highest possible ODP for any CFC, HCFC, HFC, or HFO refrigerant? Answer A. 0 B. 1 C. 100 D. Infinite B What is the least possible ODP for a refrigerant? Answer A. 0 B. 1 C. 100 D. None A What is the ODP of R-441a? Answer A. 0 B. 0.1 С. 0.2 D. 1 A What is the ODP of R-600a? Answer A. 1 B. 0 С. 0.5 D. 0.25 B Which of the following classes refers to a refrigerant that has low flammability? Answer A. 1 B. 2 С. 3 D. A B Which of the following classes refers to a refrigerant that is not flammable at all? Answer A. 1 B. 2 С. 3 D. A A. 1 Which of the following classes refers to a refrigerant with high toxicity? Answer A. 1 В. 3 С. А D. B D. B Which of the following classes refers to a refrigerant with low toxicity? Answer A. 1 В. 3 С. А D. B C. A Which gas is used as a reference for measuring Global Warming Potential? Answer CFCS HCFCs Ozone Carbon dioxide Carbon dioxide Which of the following are CFCs? (Choose all that apply) Answer R-12 R-1234yf R-20 R-11 R-12 and R-11 Which of the following are HCFCs that are seen in most refrigeration systems today? Answer R-22 R-123 R-124 R-231 R-22 Which of the following are HCFCs? (Choose all that apply) Answer A. R-22 B. R-123 C. R-124 D. R-211 A, B and C Which of the following refrigerants are HFCs? (Select all that apply) Answer R-134a R-32 R-12 R-22 R-134a and R-32 Why are HFCs still considered harmful to the environment? Answer Because they deplete the ozone layer Because they cause cancer Because they increase global warming Because they are harmful to plants Because they increase global warming Which of the following are HFOs? Answer R-134a R-1234yf R-11 R-22 R-1234yf Which of the following statements about carbon dioxide is true? (Select all that apply) Answer A. Carbon dioxide has a GWP of 1 B. Carbon dioxide has a GWP of 0 C. Carbon dioxide has an ODP of 0 D. Carbon dioxide has an ODP of 1 A and C Which of the following are natural refrigerants? (Select all that apply) Answer A. R-600a В. НС-600а C. R-134a D. R-22 A and B Which of the following is NOT a natural refrigerant? Answer R-717 R-744 R-130 R-290 R-130 Which of the following refrigerants have an Ozone Depletion Potential of greater than 0? (Select all that apply) Answer R-12 R-22 R-410a R-600a R-12 and R-22 Which safety classification of refrigerants is most dangerous to use? Answer ВЗ B2L A4 A2 B3 Which safety classification of refrigerants is most safe to use? Answer А. ВЗ B. B2L С. АЗ D. A1 D. A1 Which type of refrigerants are most harmful to the ozone layer? Answer HFOS UFOs HCFCs CFCs CFCs Which types of refrigerants are least harmful to the ozone layer? (Select all that apply) Answer CFCS HCFCS HFCs HFOs HFCs and HFOs Which types of refrigerants have the lowest GWPs? (Select two) Answer CFCs HFCS HFOs HCS HFOs and HCs Ammonia is safe to use because it is a natural refrigerant. Select one: True False False GWP is a measure of how much energy a gas traps in the atmosphere over 100 years Select one: T or F False If a gas has a GWP of 50, it means it has 50 times less global warming potential than carbon dioxide. Select one: True False False R-410a is an A1 refrigerant. It is non-toxic and has low flammability, making it one of the safest refrigerants to use. Select one: True False True The GWPs of HFOs and HCs are close to those of HCFCS. Select one: True False False The lowest number for an ozone depletion potential (ODP) is 1. Select one: True False False Which of the following statements about fractionation of refrigerants is true? (select all that apply) Answer A. Is when refrigerants settle into layers B. Happens in vapor phase C. Happens in liquid phase D. Happens in solid phase A and B What is temperature glide? Answer A. The difference between the bubble and the dew point B. The difference between the boiling point of R-22 and the replacement C. When temperature changes in a refrigerant D. None of these A What is bubble point? Answer A. The temperature at which the first refrigerant in a blend turns to liquid B. The temperature at which the first refrigerant in a blend turns to vapor C. The temperature at which the last refrigerantin a blend turns to vapor D. The same as the boiling point B What is the definition of dew point? Answer A. The temperature at which the last refrigerant in a blend turns to liquid B. The temperature at which the first refrigerant in a blend turns to liquid C. The temperature at which the last refrigerant in a blend turns to vapor D. The same as the condensation point B What is a ternary blend? Answer Three refrigerant blends combined Three refrigerants blended together Three replacement refrigerants None of the above Three refrigerants blended together Which of the following is considered retrofitting? Answer -An EPA approved process to make DIY refrigerant blends - Replacing a system that used HCFC refrigerants -Replacing HCFC refrigerants with other refrigerants -Modifying components of the system to use a new refrigerant Modifying components of the system to use a new refrigerant Which of the following are reasons to not mix your own refrigerants? Answer It is illegal It can cause equipment failure The resulting mix has unpredictabletemperatures All of the above All of the above If a refrigerant has a drop-in replacement, then no retrofit is needed. Select one: True False True In a zeotropic blend, all refrigerants have the same boiling point. Select one: True False False R-407c is an azeotropic blend. Select one: True False False Refrigerant blends need to be charged as a liquid. Select one: True False True Refrigerant blends take on the ASHRAE number of the main refrigerant in the blend. Select one: True False False Technicians can make their own EPA-approved refrigerant blends. Select one: True False False There are no drop-in replacements for R-22 refrigerant. Select one: True False True There are no retrofit refrigerants for R-22. Select one: True False False Alkylbenzene (AB) oil is used for systems with which of the following refrigerants? (Select all that apply) Answer A. CFC B. HCFC C. HCFC blends D. HFC A, B, and C Which of the following characteristics do hygroscopic oils have? Answer Break down in the presence of water Absorb moisture readily Reject moisture readily None of these Absorb moisture readily If we are retrofitting a system to use R-134a, which oil do we need to use? Answer Alkylbenzene (AB) Polyolester (POE) Mineral Oil (MO) None of the above Polyester (POE) R-1234yf is not miscible with any refrigerant oils. Select one: True False False An ideal oil is best at handling only high temperatures and high pressures. Select one: True False False An ideal oil is readily miscible with the refrigerant in the system. Select one: True False True Provided that the oil is non-flammable at both the initial and final temperatures, it is suitable for use since the system is enclosed. Select one: True False False Hydrolysis is when refrigerant oils break down in the presence of water. Select one: True False True Polyolester oils are great because they can mix with a lot of other oils. Select one: True False False Which of the following is a common way that leaks can occur? Answer Wear and tear on old equipment Poor initial construction Holes or cracks created accidentally duringconstruction All of the above All of the above Which of the following is least likely to be a common leak location in HVAC systems? Answer Piping connections HVAC fan Coils Valve connections HVAC fan Which of the following is not a reason why refrigerant leaks are a concern? Answer A. They can easily be fixed by all homeowners B. HVAC equipment won't work properly if there is a leak C. They can be costly to find and fix D. Refrigerants can be harmful to the environment A What information needs to be on the label of a container sent for reclamation? Answer A. Refrigerant type B. Date manufactured C. Cylinder type D. All of these A In what position are cylinders of refrigerant generally required to be shipped? Answer Facing the driver Upside down Upright Varies based on cylinder type Upright When shipping refrigerant that has been used, which of the following must we do? Answer Attaching DOT classification tags Use recovery cylinders Properly label contents All of the above All of the above When shipping refrigerants in hazard class 2.2, what information needs to be on the shipping paper? Answer Number of molecules in the cylinder Number of times the refrigerant has been used Number of refrigerants in the cylinder Number of cylinders of each gas Number of cylinders of each gas Where can you find any safety-related information on refrigerants you're handling? Answer Safety Information Sheets Safety Data Sheets Material Data Sheets All of these Safety data sheets When sending used refrigerants to be reclaimed, you must use disposable refrigerant cylinders. Select one: True False False Contaminated refrigerants can cause the appliance to: Answer Last longer Cool less efficiently Optimize cooling None of these Cool less effectively If a household freezer contains R-22, we can retrofit it to operate on: Answer R-12 R-600a R-410a None of these R-410a If we find refrigerant that is mixed, what should we do? Answer Destroy it Send it to the EPA to be reclaimed Send it to SkillCat to be reclaimed Send it to a certified reclaiming facility to be reclaimed Send it to a certified reclaiming facility to be reclaimed If we use nitrogen to pressurize a system or blow debris out (after fully recovering the refrigerant in the appliance), we can? Answer Recover the nitrogen into the same recovery tank as the refrigerant Vent the nitrogen Vent the refrigerant because it's useless All of these Vent the nitrogen What is isobutane? Answer R-290 An acceptable substitute for all householdrefrigerators and freezers An unacceptable substitute for newhousehold refrigerators and freezers An acceptable substitute for new household refrigerators and freezers An acceptable substitute for newhousehold refrigerators and freezers New household refrigerators and freezers can be factory charged with? Answer R-600a R-290 Both A and B None of these R-600a and R-290 Small appliances include: Answer Commercial freezers Commercial refrigerators Window AC units All of these Window AC units Up to how many pounds of refrigerant can Type I appliances contain? Answer A. 3 B. 5 C. 15 D. 50 B Which of the following statements is NOT correct? Answer Hydrocarbons are acceptable substitutes forretrofit applications Hydrocarbons are highly flammable Hydrocarbons can only be factory charged Hydrocarbons are acceptable substituteswith use conditions Hydrocarbons are acceptable substitutes forretrofit applications Which of the following is not true? Answer SNAP lists acceptable substitutes for phased out refrigerants for different categories of end-uses SNAP is implemented by the EPA Refrigerants can be classified as unacceptable under SNAP None of these None of these Which of the following statements is true about refrigerant recovery? Answer You can only sell refrigerant that is reclaimed to virgin specifications Reclaimers can refuse to accept contaminated refrigerant Reclaimers can charge extra for processing contaminated refrigerant All of these All of these Which of the following refrigerants is not covered by the sales restriction of Section 608? Answer R-717 R-134a R-22 R-12 R-717 Which of these can be vented? (Select all that apply) Answer A. R-717 B. R-744 C. R-728 D. R-134a A, B, and C Do you expect to see R-22 listed as an acceptable substitute under the SNAP program. Select one: True False False Do you expect to see R-404a in household refrigerators and freezers? Select one: True False True Do you expect to see R-407c in new household refrigerators and freezers? Select one: True False False For R-22, there are no drop-in substitutes. Select one: True False True Hermetically sealed systems are systems that cannot lose refrigerant. Select one: True False False If a humidifier has 60 ounces of R-32, it is considered a Type I appliance under Section 608. Select one: True False True If a humidifier has 90 ounces of R-32, it is considered a Type I appliance under Section 608. Select one: True False False If a water cooler has 14 ounces of R-134a, it is considered a Type I appliance under Section 608. Select one: True False True If I don't have Section 608 certification, I can buy 3 lb cans of R-134a. Select one: True False False If we have two HFC refrigerants, we can use the same recovery cylinder because they are the same type of refrigerant. Select one: True False False Low loss fittings are required for servicing systems containing ODS in order to comply with the Venting Prohibition. Select one: True False True MVACs are considered Type I appliances under Section 608 but MVAC-like systems are not. Select one: True False False New household refrigerators and freezers containing R-290 can contain 3 lbs of refrigerant. Select one: True False False Nitrogen can be used to pressurize or blow debris out of a system containing a half charge of refrigerant. Select one: True False False Only refrigerant blends without HFCs are acceptable under the SNAP program. Select one: True False False R-450a is an acceptable substitute for use in new household refrigerators and freezers under SNAP. This means new household refrigerators and freezers can be factory charged with R 450a. Select one: True False True Section 608 is part of the Clean Air Act. Select one: True False True The SNAP program could label refrigerant A as an acceptable substitute for use in a chiller but an unacceptable substitute for vending machines. Select one: True False True Trace gases used for leak detection cannot be vented because they contain ODS. Select one: True False False Type I systems can have 3 pounds of refrigerant. Select one: True False True Type I systems need to be charged before use. Select one: True False False We can retrofit an old appliance to operate on 2 lbs of R-600a. Select one: True False False We only have to recover refrigerants before servicing systems containing CFCs and HCFCs. Select one: True False False A near azeotropic blend will contain: Answer One saturation pressure value One high saturation pressure value Two saturation pressure values that are close Two saturation pressure values that have abig difference Two saturation pressure valves that are close A zeotropic blend will contain: Answer One saturation pressure value One high saturation pressure value Two saturation pressure values that are close Two saturation pressure values that have a big difference Two saturation pressure values that have a big difference Access fittings: Answer Need to be leak tested before recoveringrefrigerant Are used to gain access to closed systems Are used with window AC units All of these All of these Defrost heaters: (Select all that apply) Answer Can be used to increase the temperature of refrigerant Can be used to increase refrigerant recovery speed Are available in all Type I appliances None of these Can be used to increase the temperature and recovery speed of refrigerant If the compressor is not working and we are performing passive recovery, we need to take steps to do what? Answer Secure a recovery machine Vacate the area Ventilate the working space Release trapped refrigerant from the compressor oil Release trapped refrigerant from the compressor oil If the pressure of the system is found to be 0 psig, can we recover refrigerant from the system? Answer Yes No It depends on how much refrigerant is left It depends on the type of refrigerant No If the pressure reading and expected pressure are far apart, which of the following are possibly contained in the refrigerant? Answer Non-condensables Water vapor Nitrogen All of these All of these Let's say we have a system with an operating compressor and the capillary tube is completely restricted. How many access valves do we need to recover refrigerant from a system that is sealed? Answer One Two None It doesn't matter One Solderless piercing valves: Answer A. Tend to leak over time B. Are for permanent use C. Should not be left on the appliance afterservice Both (a) and (c) both a and c System dependent recovery: Answer Is the same as passive recovery Uses the pressure of the compressor Can be used for appliances with under 15Ibs of refrigerant All of these are correct All of these are correct We can use a known refrigerant's PT chart to see if there are non-condensables in the refrigerant. Answer Always true Only true if we can measure the refrigerants temperature Only true if we can measure the refrigerants pressure Only true if we can measure both the pressure and temperature Only true if we can measure both the pressure and temperature What is the approximate pressure of a storage container of R-22 that is stored at 75°F? Assume there are no impurities. PT Chart Answer 131 psig 308 psig 78.8 psig 22 psig 131 psig What is the approximate pressure of a storage container of R-404a that is stored at 60°F? Assume there are no impurities. PT Chart Answer 88.2 psig 108 psig 125.8 psig D. 269 psig 125.8 psig What should we do to recover refrigerant from a system with a compressor that is not working? (Select all that apply) Answer A. Tapping the compressor with the biggest a-mallet to maximize surface area B. Tapping the compressor with a rubber mallet so we don't damage iT C. Heating it with a match D. Heating it with a heating blanket B and D When performing active recovery and the compressor is working, we must recover to what levels? Answer A. 90% of the refrigerant charge B. 4 inch vacuum Both (a) and (b) Either (a) or (b) Either a or b Which method of monitoring fill level is the most accurate? Answer Gross cylinder weight Mechanical float device Electronic shut off device None of these Gross cylinder weight Which methods are approved by the EPA to monitor fill level of recovery cylinders? Answer Mechanical/ Internal Float Devices Electronic Shut Off Devices Gross cylinder weight All of these All of these Which of the following are types of low loss fittings? (Select all that apply) Answer A. Solder type low loss fittings B. Manual low loss fittings C. Automatic low loss fittings D. Hybrid low loss fittings B and C Which of the following values do we check if we suspect that non-condensables are present? Answer Refrigerant pressure Humidity Refrigerant type Refrigerant weight Refrigerant pressure You are servicing an appliance that contains R-134a. Which of the following can you use to recover the refrigerant? Answer A recovery cylinder used for HCFC-22 A recovery cylinder used for HFC-134a A disposable cylinder used for R-134a A disposable cylinder used for R-22 A recovery cylinder used for HFC-134a We need separate recovery cylinders for each class of refrigerants (e.g. HCFCs). For example, we cannot use the same cylinders to recover CFC and HCFC refrigerants. But we can use the same cylinder to recover different HCFC refrigerants. Select one: True False False An active recovery machine is required for all systems. Passive recovery is a thing of the past. Select one: True False False For both active recovery and passive recovery, we must recover 80% of the appliance charge if the compressor is not working. Select one: True False True If a refrigerant's pressure readings are not stable, we can use its temperature readings to compare to its PT chart to check for non-condensables. Select one: True False False Installing both high and low side access valves will increase recovery time. Select one: True False False Low loss fittings are only needed when recovering from appliances containing ODS and their substitutes. Select one: True False False Low loss fittings are required for servicing appliances containing CFCs, HCFCs, and HFCs because of the Venting Prohibition. Select one: True False True System dependent recovery captures refrigerant in a pressurized container to keep it fresh. Select one: True False False We generally want to leak test access fittings after a service to make sure it does not have leaks for the next service. This is to save us time from leak testing the access fitting the next time around. Select one: True False False When the compressor is not working and we are performing passive recovery, we need to access the system from both the high and low side. Select one: True False True If a recovery device cannot achieve a 4-inch vacuum, which one of the following does it have to be able to do in order to be used with Type I small appliances? (Select all that apply) A. Recover 80% of refrigerant with a working compressor B. Recover 80% of refrigerant with a non- working compressor C. Recover 90% of refrigerant with a working compressor D. Recover 90% of refrigerant with a non- working compressor B and C If the oil is contaminated, what do we have to do? Answer Flush the system Flush the compressor Flush the recovery device All of these Flush the system Non-condensables would _____ the pressure on the high side of an active recovery device. Answer Increase Decrease Have no effect on Increase Recovery devices are tested and certified by: Answer AHRI only ASHRAE only Both AHRI and UL AHRI, UL, and the EPA Both AHRI and UL The refrigerant vented off the top of charging cylinders needs to be recovered if it is: Answer An ozone depleting substance like HCFC An HFC A non-exempt substitute All of these All of these Vacuum pumps can be used to: Answer Recover refrigerant Remove air and other non-condensables Release refrigerant into the atmosphere Both (a) and (c) Remove air and other non-condensables What are the signs of refrigerant contamination? Answer A. Discolored oil B. Acidic smell C. Both (a) and (b) D. None of these C What does the process stub look like in small appliances? Answer A straight piece of tubing A straight piece of wiring A round piece of tubing None of these A straight piece of tubing What piece of equipment should we check regularly for leaks? Answer Recovery device Recovery vacuum pump Access fittings All of these Recovery device When the system pressure is found to be 0 psig, what does this indicate? Answer There has been a leak There is minimal refrigerant left in theappliance We cannot recover refrigerant All of these All of these Which of the following indicates a compressor burnout in a sealed system? Answer A pungent smell A pungent, sweet smell A pungent taste All of these A pungent smell Which of the following statements is true for small appliances? Answer The EPA requires repair of all leaks above80% of the leak rate The EPA does not require repair of leaking small appliances The AHRI Standard 740 requires repair ofleaks You should not repair leaking small appliances The EPA does not require repair of leaking small appliances Which of the following would remove non-condensables from a system? Answer A. Filter driers B. Flushing the system Both (a) and (b) Both a and b A recovery device has to achieve a 4-inch vacuum in all circumstances. Select one: True False False All recovery devices need to be tested at a place called AHRI Standard 740. Select one: True False False At high temperatures, what do CFCs and HCFCs decompose to? Answer Hydrochloric and hydrofluoric acids Hydrocarbon and hydrofluorocarbons Chloric and fluoric acids All of these Hydrochloric and hydrofluoric acids Burning CFCs and HCFCs can: Answer Create toxic vapors that are harmful to inhale Will produce phosgene gas Result from cutting or welding pipes containing residual refrigerant All of these All of these If refrigerant has been released, what is the first thing you should do? Answer Locate an exit Locate a self-contained breathing apparatus Locate a specially contained breathing apparatus Locate the leak to stop the fill of dangerous refrigerant Locate a self-contained breathing apparatus If we cannot find a SCBA, what should we do? Answer Locate an exit Vacate the area Ventilate the area All of these All of these Safety markings used in appliances with hydrocarbon refrigerants are: Answer Applied by technicians to warn other technicians Permanently made on the equipment during manufacturing Have to be put on equipment permanently by technicians All of these Permanently made on the equipment during manufacturing What is the number one cause of refrigerant-related deaths in the HVAC industry? Answer Heart attacks Refrigerant toxicity overload Fires Oxygen deprivation Oxygen deprivation What piece of equipment is needed on nitrogen tanks when using them to service an appliance? Answer Refrigerant thermometer Pressure regulator Manual gauge All of these Pressure regulator When do we need to use safety eyewear and butyl-lined gloves? Answer When testing the quality of refrigerant When moving refrigerant cylinders When connecting and disconnecting hoses •When taring the refrigerant scale When connecting and disconnecting hoses Which of the following are areas that do not need to be marked when it comes to appliances that contain HCs? Answer Outside the refrigerator Evaporators Exposed tubing Inside refrigerator door Inside refrigerator door Which of the following is needed to protect your hands from refrigerant burns? Answer Cotton gloves Butyl-lined gloves Triple layered gloves Any of the above Butyl-lined gloves How would you remove moisture from refrigerants in a system? Answer Purge the condenser Drain the oil separator Reduce water flow to the condenser Use a filter drier Use a filter drier What are refrigeration and air-conditioning compressor heaters used for? Answer To reduce the amount of refrigerant in the oil To prevent refrigerant vaporization To reduce the amount of entrained water inthe receiver To prevent acid pitting To reduce the amount of refrigerant in the oil What is a sight glass useful for? Answer Determining the type of refrigerant Checking for moisture in refrigerant Providing sub-cooling Determining the type of oil used Checking for moisture in the refrigerant What is the easiest way to check the type of refrigerant used in a 60 ton packaged rooftop unit? Answer Look at the unit nameplate Use your service gauge set and a PT chart Ask the owner Measure the condenser pressure Look at the unit name plate What is the state of the refrigerant when it's leaving the condenser coils into a receiver tank? Answer Low Pressure Liquid Low Pressure Vapor High Pressure Liquid High Pressure Vapor High pressure liquid What will backseating a suction shut-off valve close? Answer Suction line and compressor port Compressor and gauge port Compressor port Gauge port gauge port Which of the following components is located just before the compressor? Answer Receiver Accumulator Condenser coils TEV Accumulator Which of the following refrigerants is not used in Type lI systems? Answer R-407C R-407A R-245fa R-22 R-245fa Which of the following refrigerants would be used in a low-pressure appliance? Answer R-22 R-123 R-410A R-407A R-123 What date was the sale of CFC's & HCFC's restricted to technicians certified in refrigerant recovery? November 14, 1994 Section 608 of the Federal Clean Air Act requires technicians to what? Recover all refrigerants. The objective of the Clean Air Act is to protect what? The earth's stratosphere. HFC's HydroFlouroCarbon's CFC's ChloroFluoroCarbon's ODP Ozone Depletion Potential Which international treaty agreement was the basis for Section 608? The Montreal Protocol. Depletion of the ozone in the stratosphere is know to cause what 6 things? 1.Crop losses 2.Increases in eye diseases 3.Skin Cancer 4.Reduced marine life 5.Deforestation 6.Increased ground level ozone What happens when CFC or HCFC molecules get in the stratosphere & free atoms of Chlorine are set free? These atoms attack Ozone Molecules causing the formation of Chlorine Monoxide (CLO), after colliding with another Ozone Molecule, causes 2 Oxygen (O2) molecules to be made & leaving an atom of chlorine to act as "Free Agent" starting the process over until 100,000 molecules of Ozone are destroyed by just one atom of chloride. What date was recovery equipment required to be certified by a lab, & achieve higher evacuation levels, & have low loss fittings? November 15, 1993 On what date was technician certification required? November 14, 1994 What date was CFC's phased out of production? December 31, 1995 What is EPA 608 Type I certification? Persons who maintain, service, repair, or dispose of small appliances (containing 5 pounds of refrigerant (or less). What is EPA 608 Type II certification? Persons who maintain, service, repair, or dispose of high and very high pressure appliances. Except small appliances and motor vehicle air conditioning systems. What is EPA 608 Type III certification? Persons who maintain, service, repair, or dispose of low pressure appliances. What is EPA 608 Universal certification? Persons who maintain, service, repair, or dispose of both low and high pressure equipment, as well as appliances. HCFC's HydroChloroFluoroCarbons What are HydroChloroFluoroCarbons? Commonly known as HCFC's, they are a group of man-made compunds containing hydrogen, chlorine, fluorine, and carbon. A recovery cylinder must not be filled more than ___ % of it's capacity by weight? 80% How should refrigerant cylinders be shipped? Up-right with proper DOT classification tags. What oil MUST be used with ALL HFC's for HVAC/Refrigeration but will also work with CFC's and HCFC's. Polyolester HCFC's have very low atmospheric concentrations measured in parts per? Trillion All cooling systems containing more than 50 lbs. of refrigerant must be repaired when the annual leak rate exceeds___? 15% Mineral Oils are used with? All CFC's Alkebenzene is used alone or as an additive for? HCFC's (Will also work with CFC's) POE Polyolester What is the definition of a Type I Appliance? A small appliance that is manufactured, charged, and hermetically sealed in a factory with 5 Lbs. of refrigerant or less. What is the definition of a Type II Appliance? High pressure or very high pressure appliances except for small appliances and motor vehicle air conditioning. Refrigeration systems containing more than 5 Lbs. of high or very high pressure refrigerants. What is the definition of a Type III Appliance? Low pressure equipment like low pressure chillers. All refrigerants are assumed to be a single chemical if they are numbered what? 1-399 and 600 and above. What is an Azeotrope? A mixture of two or more liquids in such a ratio that it's composition cannot be changed by vaporizing it. Azeotrope's are numbered what? 500 to 599 What is fractionation? When the refrigerant leaks, it leaks out in different rates due to the different pressures. What is Temperature Glide? When the temperature of the vaporizing refrigerant changes, even though the pressure remains the same. What are the two basic types of recovery devices? Self-Contained and System-Dependent. System-Dependent devices may only be used on appliances containing how much refrigerant? 15 Lbs of refrigerant or less What MUST be placed on a refrigerant cylinder being returned for reclaiming. A refrigerant label. After completing the transfer of liquid refrigerant between a recovery unit and a refrigeration system, you should guard against what? Trapping liquid refrigerant between the service valves. When pressurizing a system with nitrogen, you should always? Charge through a pressure regulator. What are the three "R's"? Recover, Recycle, and Reclaim. In relation to the three "R's" what is Recover? To remove refrigerant in any condition from a system and store it in an external approved container. In relation to the three "R's" what is Recycle? To clean refrigerant for reuse by seperating the oil from the refrigerant and removing moisture from the refrigerant by passing it through one or more filter dryers. Can Recycled refrigerant be resold? It cannot be re-sold but it can be re-used. In relation to the three "R's" what is Reclaim? To process refrigerant to a level equal to new (virgin) product specifications as determined by chemical analysis. Can Reclaimed refrigerant be resold? Yes, but must meet the standard set forth in ARI 700 before it can be resold. What chemical has been found in the stratosphere indicating ozone depletion? Chlorine Monoxide (CLO) What are 5 Type I appliances? 1.Household refrigerators 2.Household freezers 3.Room air conditioners 4.Water Coolers 5.Drinking fountains What are 6 Type II appliances? 1.Walk-in coolers 2.Walk-in freezers 3.Reach-in refrigerators 4.Reach-in freezers 5.Residential & Commercial comfort cooling systems 6.Ice machines What is an example of a Type III appliance? Low pressure chiller. When is "Dew Point" used? When calculating Superheat. When is "Bubble Point" used? When calculating Sub-cooling. What does the EPA require on all Type I equipment that uses Class I or Class II refrigerants. EPA requires a service aperature (process stub). TXV Thermostatic Expansion Valve The EPA considers a major repair to be the replacement of what 4 items? 1.Evaporator 2.Condenser 3.Compressor 4.Auxillary Heat Exchanger When the refrigerant is put back into a Type III chiller, following recovery and system repair, where is it added? The charging valve on the evaporator. What method is used to find suspected water tube leaks in chillers? Hydrostatic (tube) test What temperature should be attained when removing oil from a low pressure system to ensure a lower level of refrigerants in the oil? 130-Degrees F The typical design burst pressure for a rupture disc is what? 15 PSIG Excessive moisture collection in the purge unit can indicate what? Tube Leakage Vacuum pumps need to be capable of pulling what level of vacuum? 500 microns All refrigeration systems containing more than 50 lbs. of refrigerant must be repaired when the annual leak rate exceeds___? 35% The most efficient method of leak checking a charged low-pressure system is to use? Controlled hot water or heater blankets. Systems with open drive compressors are prone to leak where? At the shaft seal. What does ASHRAE standard 15 require? A refrigerant monitor that will sound and alarm and automatically start a ventilation system in equipment rooms before the refrigerant concentration reaches the TLV-TWA. TLV-TWA Threshold Limit Value, Time Weighted Average A-1 Group Refrigerants only require what? Oxygen Deprivation Sensor All "B" rated refrigerants require what? "Refrigerant Specific" Mechanical Room Sensor. What are Cooling Towers? They are heat removal devices used to transfer process waste heat to the atmosphere. What is the maximum test pressure to use for pressurizing Type III centrifugal systems with nitrogen? 10 psig Enough vapor has entered the system and you may begin charging liquid refrigerant when the refrigerant saturation temperature increases to? 36F What should be done to reduce refrigerant loss from a purge unit on a R-123 chiller? Repair the leak in the system To raise the pressure of a low-pressure refrigeration system for leak checking, you can Heat the system by circulating hot water, raising the temperature of the room, or using heating blankets Low-pressure systems must be evacuated to 25 mm of Hg absolute before being discarded. Purge units are required on low-pressure chillers because? these systems operate below atmospheric pressure. What is the safety classification of R-123 B1 hydrostatic tube test kit is used to? find leaks in the tube. What is a valid reason to request an extension from the EPA on the appliance leak repair deadline? Local permit regulation make the repair within 30 days impossible AND more time is needed to obtain the necessary repair parts from the manufacturer. For low pressure chiller, it is best to begin refrigerant recovery with ______ removal to avoid freezing of the water in the chiller barrels liquid. Every recovery and recycling unit must be _____________. labeled as certified to meet EPA's requirements The best method to determine a chiller's normal charge for leak rate calculations is to use the charge stated on the equipment nameplate. What safety precautions should be adhered to for low-pressure systems? Use gloves and safety goggles when working with liquid refrigerant. If possible, the temperature of the equipment room where the chiller is located ______. Should be increased to speed recovery To prevent freezing, when recharging an evacuated water-cooled chiller system with R-123, first charge with vapor to a pressure of at least _______________. 20 in Hg vacuum When evacuating a system and the freezing of moisture in the system is preventing you from achieving a deep vacuum, it may be necessary to prevent freezing by increasing the system pressure with nitrogen The typical design burst pressure for a rupture disk on a low-pressure centrifugal air conditioning system is ______________ . 15 psig A water-cooled recovery unit typically has a _________________. lower recovery tank pressure and therefore faster recovery rate The owners and operators of any system that has 50 or more pounds of refrigerant charge must keep records of refrigerant added, leak inspections, initial verification tests, and follow-up verification tests for at least _______. 3 years The saturation pressure corresponding to 32 °F for R-123 is 20 inches of HG vacuum If an owner of a system (with 101 pounds of refrigerant charge that has a significant leak) is going to retire the system, and the replacement appliance uses refrigerant that is exempt from the venting prohibition, how much time does the owner have to retire the system? 18 months The EPA definition for the type of cooling that chillers usually provide is ___________. comfort cooling After a leaking system that has been repaired has passed the initial verification leak test, when must the follow-up verification test be conducted? within 10 days When working with low-pressure systems, the high-pressure cut off should be set to no more than _____ to avoid damaging the system or activating the pressure blow off device (rupture disk). 10 psig Non-azeotropic refrigerants leak from a system ____________. At uneven rates because of the different vapor pressures If the compressor crankcase is the coldest part of the system, refrigerant will migrate to the compressor because of the difference in ________________________ in the system Pressure The fill level of a recovery cylinder can be determined by _______________. Both mechanical float or electronic shut off devices and the weight of the cylinder. What are the characteristics of hydrofluoroolefins and hydrocarbon refrigerants? 0 ODP and low GWP If technicians lose their certification card, they must_________________. Request a replacement from the company that provided the certification Which ASHRAE refrigerant safety classification is the safest? A1 How does the GWP of R-441A compare to the GWPs of R-410A? The GWP of R-441A is significantly lower. What makes HFC refrigerants damaging to the environment? They can have very high global warming potentials. ______________ returns refrigerant to new product specifications and requires chemical analysis to verify the purity to AHRI-700 standards. Reclaiming The ability of a substance to destroy ozone in the stratosphere is referred to as ___________________. ODP (Ozone Depletion Potential) The pressure range that is typically displayed on a high-pressure manifold gauge is ______. 0 to 800 psig HFO refrigerants are miscible in_________________ lubricants? POE lubricants All new recovery equipment must __________________________. Be EPA approved and have an EPA-approved certification label attached. _________________ make(s) HFO refrigerants less flammable than HC refrigerants. Fluorine An example of an HCFC refrigerant is: R-123 Long hoses between the unit and the recovery machine_______________. Can cause excessive pressure drop and increased recovery time. EPA recommends this service practice to conserve refrigerant. Find and repair leaks in the system. What is being done in the U.S. to stop damage to the stratospheric ozone layer? Eliminating the use of CFCs and HCFCs refrigerants. ______________ contains chlorine. R-22 Never fill a refillable refrigerant cylinder beyond _________________. 80% of its capacity by weight The high-pressure gauge on a typical gauge manifold set is typically colored______________. Red Before recharging any flammable hydrocarbon or HFO refrigerant, always ______________. Electrically ground the recovery machine and recovery tank, verify the refrigeration system is grounded, install a fresh filter drier, successfully complete a standing-pressure leak check at the maximum system pressure, and then evacuate to at least 500 microns. When a system is operating, refrigerant leaves the condenser as a ______________. high pressure liquid If the refrigerant in a system is suspected to be contaminated, you can ________. turn the refrigerant in for reclamation The 80% fill level in a recovery tank can be determined by _______________ A float switch in the recovery tank. ________________is an approved refrigerant for new household refrigerators, freezers, and combination refrigeration/freezers. R-600a You must have a self-contained recovery machine available unless you only work on ________________. Small appliances The maximum allowable factory charge for a Type I appliance is 5 pounds Small appliance servicing requires a ___________ or Universal certification. Type 1 When recovering refrigerant using a passive recovery system and the system has an inoperative compressor, it is ______________. Helpful to heat and strike the compressor with a rubber mallet to release any refrigerant trapped in and under the compressor oil. If a large leak of refrigerant occurs, _________________________. Immediately vacate and naturally ventilate the area. Recovery of refrigerant cannot begin if the initial pressure in the system is ___________. 0 psig If a recovery cylinder is suspected to be contaminated, measure ________. the pressure of the refrigerant in the cylinder A passive recovery device can be used for ________________. Both a small commercial walk-in freezer with a charge of 14 pounds and a domestic refrigerator with a charge of 3 pounds. Which maintenance practice should be performed on a regular basis? Change the vacuum pump oil, check the recovery equipment for leaks, and check the manifold hose set for leaks. Anytime pressurized nitrogen is put into a system, the nitrogen gas __________. may be vented to the ambient air. An exempt refrigerant is any refrigerant that has a zero-ozone depletion potential (0 ODP) and a global warming potential (GWP) equal to or lower than carbon dioxide, that is a GWP of ___ or less. 1 You must know the _______________ before beginning a refrigerant recovery. type of refrigerant that is in the system. A process stub is a ____________________ straight piece of tubing that is entered using a piercing access valve. When recovering refrigerant from a small appliance with a working compressor, you must recover the refrigerant to a vacuum of _________________. 4 inches of mercury or 90% of the remaining charge. Which refrigerant does not need to be recovered? R-744 When checking for non-condensables, _______________. Make certain the pressure and the temperature of the refrigerant are stable and known. Why do manifold gauge set hoses have self-sealing connectors or hand valves on the ends of the hoses? They are required by the EPA, and to minimize refrigerant losses when the hoses are connected and disconnected to the system. For a belt-driven non-hermetic compressor system, the _____________________ is most likely to leak if the system has not been operated for several months. Shaft seal The indicating strip in a sight glass indicates if ___________ is present in the refrigerant by changing color. Moisture After January 1, 2019, any com