Podcast
Questions and Answers
Which type of refrigerants typically has the lowest global warming potential?
Which type of refrigerants typically has the lowest global warming potential?
How does the global warming potential of R-410A compare to carbon dioxide?
How does the global warming potential of R-410A compare to carbon dioxide?
It is thousands of times greater
How do the global warming potentials of isobutane (R-600a), propane (R-290), and R-441A compare to the GWPs of HFC-134a, R-404A, and R-410A?
How do the global warming potentials of isobutane (R-600a), propane (R-290), and R-441A compare to the GWPs of HFC-134a, R-404A, and R-410A?
They are significantly lower
What is the state of the refrigerant entering the compressor of a refrigeration system?
What is the state of the refrigerant entering the compressor of a refrigeration system?
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Which type of lubricants are HFO refrigerants miscible in?
Which type of lubricants are HFO refrigerants miscible in?
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Which of the following gases help form the earth's protective shield?
Which of the following gases help form the earth's protective shield?
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What does ozone depletion potential (or 'ODP') measure?
What does ozone depletion potential (or 'ODP') measure?
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Which of the following refrigerants have an ozone depletion potential of more than zero?
Which of the following refrigerants have an ozone depletion potential of more than zero?
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HCFC refrigerants contain which of the following?
HCFC refrigerants contain which of the following?
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What must be done before disposing of any appliance containing a CFC, HCFC, or HFC refrigerant?
What must be done before disposing of any appliance containing a CFC, HCFC, or HFC refrigerant?
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A major system repair is being performed on an R-22 appliance. What CANNOT be done to recharge the appliance?
A major system repair is being performed on an R-22 appliance. What CANNOT be done to recharge the appliance?
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Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) have which of the following in common?
Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) have which of the following in common?
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Under EPA's regulations, what standard must reclaimed refrigerant meet before it can be resold?
Under EPA's regulations, what standard must reclaimed refrigerant meet before it can be resold?
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Which of the following appliances is NOT covered by EPA Section 608 regulations?
Which of the following appliances is NOT covered by EPA Section 608 regulations?
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EPA does NOT require technicians (or the company employing the technician) to keep which of the following records when disposing of appliances with 5-50 pounds of refrigerant?
EPA does NOT require technicians (or the company employing the technician) to keep which of the following records when disposing of appliances with 5-50 pounds of refrigerant?
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What synthetic lubricant is presently used with ternary blends containing HCFCs?
What synthetic lubricant is presently used with ternary blends containing HCFCs?
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How do refrigerant blends leak from a system?
How do refrigerant blends leak from a system?
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In which component of a system does the refrigerant change from a high-pressure vapor to a high-pressure liquid?
In which component of a system does the refrigerant change from a high-pressure vapor to a high-pressure liquid?
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Which process applies to cleaning refrigerant for immediate reuse by oil separation and single or multiple passes through devices, like replaceable core filter driers, which reduce moisture and acidity?
Which process applies to cleaning refrigerant for immediate reuse by oil separation and single or multiple passes through devices, like replaceable core filter driers, which reduce moisture and acidity?
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What gas should be used to leak check a system designed for use with R-410A that has been opened for a major system repair?
What gas should be used to leak check a system designed for use with R-410A that has been opened for a major system repair?
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Why is it important NOT to mix different refrigerants in the same container when recovering refrigerant?
Why is it important NOT to mix different refrigerants in the same container when recovering refrigerant?
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Over-evacuation of a system occurs.
Over-evacuation of a system occurs.
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According to the ASHRAE refrigerant safety classification standard, which of the following designations would be the safest?
According to the ASHRAE refrigerant safety classification standard, which of the following designations would be the safest?
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Why should care be used not to overfill refrigerant storage cylinders?
Why should care be used not to overfill refrigerant storage cylinders?
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The Department of Transportation regulations require which parameter to be recorded on the shipping paper for hazard class 2.2 Nonflammable Compressed Gases?
The Department of Transportation regulations require which parameter to be recorded on the shipping paper for hazard class 2.2 Nonflammable Compressed Gases?
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Which of the following refrigerants has the lowest global warming potential?
Which of the following refrigerants has the lowest global warming potential?
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What characteristic(s) of CFCs and HCFCs make them more likely to reach the stratosphere than most other compounds containing chlorine?
What characteristic(s) of CFCs and HCFCs make them more likely to reach the stratosphere than most other compounds containing chlorine?
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What characteristic of HFC refrigerants make them damaging to the environment?
What characteristic of HFC refrigerants make them damaging to the environment?
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Which of the following refrigerants contain chlorine?
Which of the following refrigerants contain chlorine?
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When working with an appliance containing HCFCs or HFCs, which of the following does NOT require a person to be a Section 608 certified technician?
When working with an appliance containing HCFCs or HFCs, which of the following does NOT require a person to be a Section 608 certified technician?
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Which of the following is not a reason to recover refrigerants?
Which of the following is not a reason to recover refrigerants?
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In which of the following scenarios can refrigerant be vented?
In which of the following scenarios can refrigerant be vented?
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What range is displayed on a high pressure gauge on a service manifold?
What range is displayed on a high pressure gauge on a service manifold?
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Why do EPA regulations require appliances to have a service aperture or process stub?
Why do EPA regulations require appliances to have a service aperture or process stub?
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Which of the following releases of a refrigerant is illegal?
Which of the following releases of a refrigerant is illegal?
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Which types of refrigerant can only be sold to persons who have successfully passed the EPA's Section 608 certification exam?
Which types of refrigerant can only be sold to persons who have successfully passed the EPA's Section 608 certification exam?
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What is the center port on a three-port manifold used for?
What is the center port on a three-port manifold used for?
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What is the term for removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in any way?
What is the term for removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in any way?
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You have to leak-check a unit which has lost a complete charge. Which gas(es) would cause the least damage to the environment?
You have to leak-check a unit which has lost a complete charge. Which gas(es) would cause the least damage to the environment?
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What effect will low ambient temperatures have on recovery?
What effect will low ambient temperatures have on recovery?
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Which of the following is a reason to heat a system during dehydration?
Which of the following is a reason to heat a system during dehydration?
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When pressurizing a refrigeration system with nitrogen what rule should you always follow?
When pressurizing a refrigeration system with nitrogen what rule should you always follow?
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Under what conditions may you use a disposable cylinder to recover refrigerant?
Under what conditions may you use a disposable cylinder to recover refrigerant?
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What must be done before shipping any used refrigerant in a cylinder?
What must be done before shipping any used refrigerant in a cylinder?
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What are the characteristics of hydrofluoroolefins (HFOs)?
What are the characteristics of hydrofluoroolefins (HFOs)?
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Why are some hydrofluoroolefins (HFO) refrigerants classified as 'A2L'?
Why are some hydrofluoroolefins (HFO) refrigerants classified as 'A2L'?
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What does ozone in the stratosphere above the earth consist of?
What does ozone in the stratosphere above the earth consist of?
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Which refrigerant does not contain chlorine?
Which refrigerant does not contain chlorine?
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From which of the following does the ozone layer protect the earth?
From which of the following does the ozone layer protect the earth?
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What is the name of EPA's program that identifies refrigerants with lower overall risks to human health and the environment?
What is the name of EPA's program that identifies refrigerants with lower overall risks to human health and the environment?
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The date when the production and import of new R-22 in the U.S. ends is?
The date when the production and import of new R-22 in the U.S. ends is?
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Which of the following is a lawful use of HCFC-22?
Which of the following is a lawful use of HCFC-22?
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Which of the following is considered an unacceptable release of CFC, HCFC, or HFC refrigerant?
Which of the following is considered an unacceptable release of CFC, HCFC, or HFC refrigerant?
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Which of the following is a 'high-pressure refrigerant' under EPA's refrigerant recycling regulations?
Which of the following is a 'high-pressure refrigerant' under EPA's refrigerant recycling regulations?
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What is a ternary blend refrigerant?
What is a ternary blend refrigerant?
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Which of the following is not a 'refrigerant' as it is used in Section 608 of the Clean Air Act?
Which of the following is not a 'refrigerant' as it is used in Section 608 of the Clean Air Act?
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How does cooling occur in a direct expansion vapor compression refrigeration system?
How does cooling occur in a direct expansion vapor compression refrigeration system?
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What is the strongest evidence that HCFCs are in the stratosphere?
What is the strongest evidence that HCFCs are in the stratosphere?
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Which of the following refrigerant releases is considered a violation of the prohibition on venting?
Which of the following refrigerant releases is considered a violation of the prohibition on venting?
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Although the saturation pressure temperature behavior of two refrigerants might be similar, of all the following characteristics of the refrigerants being compared what must also be considered?
Although the saturation pressure temperature behavior of two refrigerants might be similar, of all the following characteristics of the refrigerants being compared what must also be considered?
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Study Notes
Refrigerants and Global Warming Potential
- HFOs (hydrofluoroolefins) generally have the lowest global warming potential among refrigerants.
- R-410A's global warming potential is thousands of times greater than CO2.
- Isobutane (R-600a), propane (R-290), and R-441A have significantly lower global warming potentials than HFC-134a, R-404A, and R-410A.
Refrigerant Characteristics and Behavior
- Refrigerant enters the compressor as low-pressure vapor.
- HFO refrigerants are miscible in POE (polyolester) lubricants.
- Stratospheric ozone contributes to the earth's protective shield against UV radiation.
- Ozone depletion potential (ODP) quantifies a substance's capability to destroy ozone in the stratosphere.
Disposal and Recovery Regulations
- R-123 and R-22 have an ozone depletion potential greater than zero.
- CFCs, HCFCs, and HFCs must be recovered before opening or disposing of any appliance containing them.
- EPA regulations necessitate recovering refrigerant before disposing of equipment containing CFC, HCFC, or HFC refrigerants.
EPA Standards and Compliance
- Reclaimed refrigerant must meet AHRI 700 standards for resale.
- Appliances not covered by EPA Section 608 regulations include desiccant dehumidifiers.
- Technicians do not need to keep model and serial numbers of appliances with refrigerant between 5-50 pounds during disposal.
Refrigerant and Equipment Usage
- Topping off an R-22 appliance with R-410A is not permitted during major system repairs.
- Synthetic lubricants for ternary blends containing HCFCs include alkylbenzene.
- Refrigerant blends leak from systems at uneven rates due to differing vapor pressures.
Recovery and Recycling Processes
- Refrigerant changes from high-pressure vapor to high-pressure liquid in the condenser.
- Recycling involves cleaning refrigerant through oil separation and filtration.
- Pressurized nitrogen is used to leak check systems designed for R-410A.
Safety Regulations and Practices
- Mixing different refrigerants in the same container makes reclamation impossible.
- Care is required not to overfill refrigerant storage cylinders to avoid internal explosions.
- EPA requires proper labeling of used refrigerant containers before shipping.
Environmental Impact and Prevention
- HFO refrigerants are non-ozone depleting with low global warming potentials.
- HFCs can have very high global warming potentials, making them environmentally damaging.
- Venting refrigerants from recovery machines is illegal and considered a violation.
Technical Specifications and Equipment Knowledge
- High-pressure gauges on service manifolds display a range of 0 to 800 psi.
- New recovery equipment must have an EPA-approved certification label.
- Short, wide piping connections to vacuum pumps optimize efficiency.
Hydration and Testing Compliance
- High-pressure refrigerant containers undergo hydrostatic testing every five years.
- Safety data sheets (SDS) should be reviewed when dealing with chemicals and refrigerants.
- Incompatible elastomers for seals and gaskets with HFO refrigerants include silicone.
Miscellaneous Key Points
- Recovering refrigerant refers to the untested storage of refrigerants in external containers.
- Dispose of mixtures of R-410A added to R-22 systems in separate recovery tanks.
- The latent heat of evaporation is a critical factor in comparing refrigerants despite similar saturation pressure and temperature behaviors.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on refrigerants and their global warming potentials. This quiz covers key concepts related to HFOs, R-410A, and comparisons with other refrigerants. Perfect for those studying environmental science and HVAC systems.
