Intro Flashcards
What are CFC’s
Chloro-fluoro-carbons
(Chlorine, Flourine & Carbon)
What are HCFC’s
Hydro-Chloro-Fluoro-carbons
Hydrogen, Chlorine, Fluorine & Carbon
What is SOD
Stratospheric Ozone Depletion
What is a TEV
Thermostatic Expansion Valve
What is the heart of the vapor-compression refrigeration cycle
The compressor
Minor releases of refrigerant, when connecting or disconnecting hoses for service or recovery is considered to be?
A “de-minimus release.”
A single chlorine atom can destroy up to ____ ozone molecules?
100,000 ozone molecules
The chlorine in CFC’s and HCFC’s will not ____ in _____, or break down into compounds that Will ____ in _____, so they do not ____ out of the ______.
devolve in water
devolve in water
Rain out of the atmosphere
What is a HFC?
Hydro-Flourine-Carbon
Hydrogen, Fluorine, Carbon.
HFC’s do not contain ____ that effects the ____ ____, but most HFC’s have a high ____ ____ ____.
Chlorine that effects the ozone layer
Global Warming Potential (GWP)
What is ODP?
Ozone Depletion Potential
What is GHG
Green House Gases
ASHRAE has grouped refrigerants by Class __ (______) or Class __ depending on their _______ level to humans.
__________ is indicated by a 1 (no _________), 2 (low __________), or 3 (high ____________).
by Class A (safest) or Class B depending on their toxicity level to humans.
Flamibility, no flamability, low flamability, high flamability
Companies and or service technicians who violate Clean Air Act provisions may lose their ___________ be required to appear in Federal Court and be fined up to $XX,XXX per day per violation.
certification
$44,539 per day, per year
What are the three R’s
Recovery - Recycle - Reclaim
What are the three R’s
Recovery - Recycle - Reclaim
What is this process know as:
Remove refrigerant, in any condition, from a system and store it in an external container to be put back into the same system, recycled, or reclaimed.
Recovery
What is this process known as:
Clean refrigerant by separating the oil from the refrigerant and removing moisture and other contaminants from the refrigerant by passing it through one or more filter driers. Recycled refrigerants may be placed back into the same system they came from or another system that is owned by the same owner.
Recycle
What is this process known as:
Process refrigerant to a level equal to new (virgin) product specifications as determined by chemical analysis. Reclaimed refrigerants must meet AHRI 700 Standards before they can be reused or sold to another user.
Reclaim
What is R-134a?
R-134a: (Tetrafluoroethane) is an HFC with an ozone depletion potential (ODP) of zero (0) and global warming potential (GWP) 1,430 times greater than carbon dioxide. R-134a is a medium-range pressure refrigerant used in auto, domestic refrigeration and commercial industries.
What is R-410A?
R-410A: (Hydrofluorocarbon) is a high-pressure, HFC refrigerant with an ODP of zero (0) and global warming potential (GWP) 2,090 times greater than carbon dioxide. R-410A is a near azeotrope refrigerant that does not fractionate during phase change in HVACR equipment. One disadvantage of R-410A is the operating pressure is approximately 50% higher than R-22 and cannot be considered as a replacement for retrofitting existing systems.
What is R-1234yf?
R-1234yf: (Tetrafluoropropene) R-1234yf is a medium pressure, HFO refrigerant with an (ODP) of 0 and global warming potential (GWP) only 4 times greater than carbon dioxide.
Recovery Devices
Refrigerant recovery and/or recycling equipment manufactured after ______ __, ____ must be certified and labeled by an ___ approved equipment testing organization to meet ___ standards.
November 15, 1993
EPA - EPA
What are the two basic types of recovery devices?
There are two basic types of recovery devices:
1) “System-dependent” which captures refrigerant with the assistance of components in the
appliance from which refrigerant is being recovered. (Figure 4)
2) “Self-contained” which has its own means to draw the refrigerant out of the applianc e.
(Figure 5)
What does SNAP stand for?
The Significant New Alternatives Policy program (SNAP) identifies and evaluates substitute refrigerants.
Compressor
Suction line into the compressor and hot gas line out.
Low-pressure, low- temperature superheated refrigerant vapor entering the compressor is compressed, changing it to a high-pressure, high-temperature, superheated vapor. It then moves to the condenser.
From the evaporator - Low pressure vapor enters compressor, high pressure vapor exits to the condenser.
What are the basic parts of the refrigerant cycle?
Compressor - condenser - metering device - evaporator - back to compressor
- May include liquid receiver between condenser and metering device and
- suction accumulator between evaporator and compressor)
________ is the absence of ___________.
Cold is the absence of heat.
- The synthetic lubricant presently used with ternary blends containing HCC’s is:
A) alkylbenzene
B) mineral oil
C) esters
D) natural oil
A) alkylbenzene
- Esther based oils can be mixed with:
A) no other oils
B) paraffin is mineral oils only
C) alkylbenzene oils only
D) mineral oils
A) no other oils
- CFC’s will no longer be manufactured or imported into the United States after:
A) 1994
B) 1995
C) 1996
D) 1997
B) 1995
- Refrigerant cannot be called “reclaimed” unless it is:
A) was processed in a reclaiming machine
B) has been chemically analyzed and refrigerant meets the ARI-700 purity standard
C) is recovered from a system less then 1 year old
D) is recovered from a system still under warrantee
B) has been chemically analyzed and the refrigerant meets the ARI-700 purity standard
- The EPA can require a technician to demonstrate their ability to perform proper procedures for recovering and/or recycling refrigerant. failure to demonstrate competency, can result in:
A) revocation of the technician’s certification
B) seizure of the technician’s recovery or recycling equipment
C) seizure of any refrigerant purchased by the technician which is still in his/her possession
D) mandatory attendance at a refrigerant training camp
A) revocation of the technician’s certification
- What characteristics of CFCs make them more likely to reach the stratosphere than most other compounds contain chlorine?
A) refrigerant that contain chlorine, but not hydrogen, are so stable that they do not break down in the lower atmosphere after being released. The chlorine or bromine reacts with ozone, causing it to change back to oxygen, thus destroying the ozone layer
B) cFCs are lighter than other damaging compounds, making it easier for them to float upwards when released
C) cFC’s are attracted to the static in the atmosphere
D) CFCs are attracted to dust in the atmosphere
A) refrigerant that contain chlorine, but not hydrogen, are so stable that they do not break down in the lower atmosphere after being released. The chlorine or bromine reacts with ozone, causing it to change back to oxygen, thus destroying the ozone layer
- Disposable refrigerant containers are used for ___________ refrigerant.
A) recycled
B) recovered
C) virgin
D) both A and B
C) virgin
- Which refrigerant is an HCFC?
A) R-124
B) R134a
C) R-410a
D) R-12
A) R-124
- What statement is true about an azeotropic refrigerant mixture?
A) it is always made from just to components
B) it has a pressure-temperature curve identical to one of its components
C) it is a mixture that is always made from at least three component refrigerants
D) it is a mixture that acts like a single-component refrigerant over its entire range
D) it is a mixture that acts like a single-component refrigerant over its entire range
- Chlorofluorocarbons (CFC’s) and Hydrochlorofluorocarbons (HCFC’s) have which of the following in common?
A) they have identical ODP’s
B) they both contain hydrogen
C) they have the same normal boiling points
D) they must be recovered before opening or disposing of appliances
D) they must be recovered before opening or disposing of appliances
- To scrap a disposable cylinder, the internal cylinder pressure should be reduced to at least:
A) 0 PSIG
B) 15 PSIG
C) 20 psi G
D) 28.8 psi
A) 0 PSIG
- In general, blended refrigerants should be charged:
A) as a vapor
B) at very high temperatures
C) as a liquid
D) the same as any other refrigerant.
C) as a liquid
- Blended refrigerants leak from a system:
A) faster than other refrigerants
B) in uneven amounts due to different vapor pressures.
C) slower than other refrigerants.
D) Only if the joint fails completely.
B) in uneven amounts due to different vapor pressures
- In a refrigerant system, the device that changes a low pressure vapor to a high pressure vapor is the:
A) evaporator
B) expansion device
C) compressor
D) condenser
C) compressor
- Data shows that chlorine in the stratosphere comes mainly from CFCs rather than from natural sources, such as volcanoes because:
A) rise in the amount of chlorine in the stratosphere matches the rise in the amount of flooring, which has different natural sources than chlorine.
B) the rise in the amount of chlorine in the stratosphere matches the rise and CFC emissions
C) air samples taken from the stratosphere over erupting volcanoes shows that volcanoes contribute a small quantity of chlorine to the stratosphere when compared to CFC’s
D) All of the above
D) all of the above
- An award of up to what amount may be paid to a person supplying information that leads to a penalty against a technician who is intentionally venting?
A) $5000
B) $10,000
C) $27,000
D) $37,000.
B) $10,000
24) which refrigerant is an HCFC?
A) R – 123
B) R – 134a
C) R – 410a
D) R – 12
A) R-123
- Have the refrigerants listed below, which has the lowest ozone depletion potential?
A) R – 22
B) R – 11
C) R – 12
D) R – 113
A) R-22
- An example of an HFC refrigerant is:
A) R – 12
B) R – 22
C) R – 123
D) R – 134A.
D) R - 134a
- Whenever dry nitrogen from a portable cylinder is connected to a system, what item is the most importance in consideration for safety?
A) The regulator has a new set of gauges.
B) The pressure gauges are clean
C) There is a relief valve in the downstream line from the pressure regulator
D) No refrigerant lines can leak.
C) there is a relief valve in the downstream line from the pressure regulator
- An example of a HFC refrigerant is:
A) R – 11
B) R – 124
C) R – 142b
D) R – 410a.
D) R-410a
- What refrigerant is an HCFC?
A) R– 22
B) R – 134a
C) R – 410a
D) R – 12.
A) R-22
- It is important not to mix R – 22 and R – 410 a refrigerant in the same container because:
A) The mixture may be impossible to reclaim
B) The mixture will explode
C) The mixture is corrosive
D) They use different oils.
A) the mixture may be impossible to reclaim
- When using recovery unit, the fill level of the recovery tank can be controlled by:
A) a mechanical float switch
B) an electronic shut off device
C) weight
D) all the above.
D) All of the above
- Never use an open flame to heat a refrigerant tank because:
A) It can result inventing refrigerant to the atmosphere
B) The tank may explode, causing serious injury to people nearby.
C) Refrigerant in the tank may decompose, forming a toxic material,
D) All of the above.
D) all of the above
- What is the best proof that CFCs are in the stratosphere?
A) The theory of some professors in California
B) Measurement of CFCs in smog
C) Measurements of CFC’s and air samples from the stratosphere
D) Measurement of other man-made compounds in the air samples from the stratosphere.
C) measurement of CFC‘s in air samples from the stratosphere
- The recovery of refrigerants is necessary to:
A) Maintain adequate supplies for service calls after the production bands
B) Prevent the venting of refrigerant to the atmosphere
C) Prevent stratospheric ozone depletion
D) All the above.
D) All the above
- Which type of refrigerant is the most harmful to the stratospheric ozone?
A) Refrigerant containing bromine.
B) Refrigerants containing chlorine.
C) Refrigerant containing hydrogen.
D) Refrigerant containing fluoride.
A) refrigerant containing bromine
- According to the EPA, a ____________leak detection methods is considered to be the most effective for locating the general area of a small leak.
A) standing vacuum test
B) electronic or ultrasonic test
C) halide torch
D) audible sound.
B) electronic or ultrasonic tester
- Long hoses between the unit and the recovery machine should not be used because they caused:
A) Excessive pressure
B) Increased recovery time.
C) Increased emissions.
D) All the above.
D) all of the above
- R – 410 a is not a typical blended refrigerant because:
A) It is a near easy, tropic refrigerant
B) It can be charged as either a liquid or vapor.
C) It has a 400 series refrigerant number it behaves like a 500 series refrigerant
D) All the above are true.
D) All of the above are true
- A ternary refrigerant blend is a ________ part mixture.
A) two-part
B) Three part.
C) Four part.
D) Five part.
B) Three part.
- Which of the following is an approved drop-in service replacement for our 12?
A) HFC – 134a
B) HFC – 410A
C) R – 407C
D) According to the EPA, there are no drop-in replacements.
D) According to the EPA, there are “no drop” in replacements.
- What effects can ozone depletion have on the environment?
A) Reduced crop yields
B) Reduced Marine life
C) Increased ground-level ozone
D) All the above
D) All the above.
- Which chemicals are controlled by the Montreal protocol?
A) Chloralfloralcarbons
B) Hydrochlorofluorocarbons
C) Halons
D) All the above.
D) All above.
- It has been illegal to vent substitutes for CFC and HCFC refrigerants sense:
A) June one, 1992
B) July 15, 1993
C) November 1993
D) November 1995
D) November 1995.
- Never use oxygen or compressed air to pressurize a system because:
A) When mixed with compressor oil or some refrigerants, it could explode.
B) Leaking oxygen or compressed air are more difficult to detect than nitrogen
C) The pressures produced by either oxygen or compressed air or not as good as nitrogen pressures
D) Oxygen and compressed air do not mix with refrigerates
A) when mixed with compressor oil or some refrigerants, it could explode
- Even though R – 22 is considered non-toxic, it:
A) Is lighter than air
B) Can cause asphyxia
C) Is a class I refrigerant
D) Can be detected by its color.
B) can cause asphyxia
- A system is dehydrated, too:
A) Remove oil and oil vapor
B) Remove water and water vapor
C) Remove refrigerant and refrigerant
D) None of the above
D) Remove water and water vapor from the
- The type of oil that is most commonly used in stationary air conditioning applications with HFC – 410 a refrigerant is:
A) ester oil
B) alkylbenzene oil
C) mineral oil
D) all oils are compatible with HFC – 410A
A) ester oil
- Technicians receiving a passing grade on the type II (medium-pressure, high-pressure and very high-pressure) exam are certified to recover refrigerant during the maintenance, service, or repair of medium and high-pressure equipment, and very high-pressure refrigerant, including:
A) CFC–13
B) HFC–410A
C) CFC–503
D) With type II certification, you are certified for all very high-pressure refrigerants, including CFC–13 and CFC–503.
D) With type two certification, you are certified for all very high-pressure refrigerants including CFC–13 and CFC-503
- Recovery equipment that relies upon the pressure of the refrigerant in the appliance would be considered
A) System-dependent
B) Self-contained
C) Illegal
D) Self-sufficient
A) System-dependent
