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161 Cards in this Set
- Front
- Back
Refrigeration technicians who violate the Clean Air Act can: |
Lose their epa cert, be fined, &be required to appear in federal court ( all of the above) |
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Which refrigerant is an HCFC? |
R-124 |
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Disposable refrigerant containers are used for______ refrigerant. |
Virgin |
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A system considered dehydrated when: |
The vacuum indicator shows you have reached and held the required finished vacuum |
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An example of an HFC refrigerant is: |
R-134a |
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After 1995 any supplies of CFC refrigerant to service existing units in the USA can only come from: |
Recovery & recycling |
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Refrigerant that is recovered can be returned to: |
The same system or other systems owned by the same person without restriction. |
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Refrigerant can not be called "reclaimed" unless it |
Had been chemically analyzed and the refrigerant meets the ARI-700 purity standard. |
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The EPA can require a technician to demonstrate their ability to perform proper procedures for recycling and or recovering refrigerant. Failure to demonstrate competency can result in: |
Revocation of the technician's certification |
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What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine? |
Refrigerants 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. |
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What statement is true about an azeotropic refrigerant mixture? |
It is a mixture that acts like a single component refrigerant over its entire range |
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Chlorofluorocarbons(CFCs) and hydrochlorofluorocarbons (HCFCs) have which of the following in common? |
Must be recovered before opening or disposing of appliances |
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Scrap a disposable cylinder the internal cylinder pressure should be reduced to at least: |
0 psig |
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Manifold gauge sets are often color coded when this is done the high pressure gauge is color coded: |
Red |
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In general Blended refrigerant should be charged: |
As a liquid |
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Blended refrigerants leak from a system: |
In uneven amounts due to different Vapor pressures |
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Which of the following gases help form the Earth's protective shield? |
Stratospheric ozone |
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In a refrigerant system the device that changes a low pressure Vapor to a high pressure vapor is the: |
Compressor |
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Data shows that chlorine in the stratosphere comes mainly from CFCs rather than from natural sources such as volcanoes because: |
All of the above |
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Which atom of the CFC molecule causes ozone depletion? |
Chlorine |
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The ozone layer protects the Earth from: |
Ultraviolet radiation from the Sun |
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When using with any solvent cleaner chemical refrigerant you should review: |
MSDS |
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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? |
$10,000 |
|
The Montreal protocol is |
A treaty among nations that control production of CFCs and HCFCs |
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Which refrigerant is an HCFC? |
R-123 |
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What is one of the most serious results of damage to the ozone layer? |
Increases in human skin cancer |
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Of the refrigerants listed below which has the lowest ozone depletion potential? |
R-22 |
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To determine the maximum allowable pressure to use when checking a system check |
The design pressure on the equipment nameplate |
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To determine the maximum allowable pressure to use when checking a system check |
The design pressure on the equipment nameplate |
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Ozone depletion potential or ODP is |
A measure of the ability of CFCs and HCFCs to destroy ozone |
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Whenever dry nitrogen from a portable cylinder is connected to a system what item is of most important in consideration of Safety? |
There is a relief valve in the downstream line from the pressure regulator |
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During servicing of a refrigeration system containing R-12 the refrigerant must be: |
Recovered |
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Which safety precaution(s) should always be followed |
All of the above never apply an open flame to refrigerant cylinder never cut weld any refrigerant line when refrigerant is in the line never use oxygen to purge lines or to pressurize a system |
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In a vapor compression refrigeration system cooling occurs when: |
Refrigerant liquid turns to a vapor |
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The evacuation of a system is a method of |
Dehydration |
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Each chlorine atom in the stratosphere can destroy _____ ozone molecules |
100000 |
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An example of a HFC refrigerant is |
R-410a |
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Which gas(es) would cause the LEAST damage to the environment during a leak check? |
Dry nitrogen |
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Refrigerant migrates to the compressor crankcase because of a difference in _______ between the refrigerator and the oil |
Vapor pressure |
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Which refrigerant is an HCFC? |
R-22 |
|
It is important not to mix R-22 and R-410a refrigerant in the same container because: |
The mixture may be impossible to reclaim |
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When using Recovery Unit The Fill level of the recovery tank can be controlled by |
All of the above a mechanical float switch and electronic shut off device weight |
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Which of the following refrigerants releases is a violation of the EPA prohibition on venting? |
Release of mixtures of nitrogen and refrigerant that result from adding nitrogen to a fully charge Appliance to leak check the appliance. |
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Which of the following human health effects could result from an increase in ultraviolet radiation? |
An increase in cataracts cases |
|
Never use an open flame to heat a refrigerant tank because |
All the Above can result in venting refrigerant to the atmosphere tank may explode causing Serious injury to people nearby refrigerant tank may decompose forming a toxic material |
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When transporting cylinders containing used refrigerant the DOT requires that you |
Attach DOT classification tags |
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According to a ASHRAEs 1992 refrigerant safety classification which of the following designations would be the most safest? |
A1 |
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The over evacuation of a system |
Does not occur |
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Equipment covered by EPA regulations include |
All air conditioning and Refrigeration equipment using CFC HCFC or HFC refrigerants |
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Never overfill refrigerant storage cylinders because |
The internal pressure of the cylinders may rise in heated areas and cause an explosion |
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It is important not to mix different refrigerants in the same container because |
The mixture may be impossible to reclaim |
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Manifold gauge sets are often colour-coded when this is done the low pressure gauge is color coded |
Blue |
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All devices used for refrigerant recovery must |
Meet EPA standards |
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Reusable refrigerant containers that are normally under any pressure above 15 PSIG must be hydrostatically tested and date stamped every |
5 years |
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Which refrigerant must be recovered before opening a system or disposing of a system |
All refrigerants must be recovered (R-410a,R-470c,R-134a) |
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To obtain an accurate Vacuum readings during system evacuation the system vacuum gauge should be located |
As far from the vacuum pump as possible |
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What is the best proof that CFCs are in the stratosphere? |
Measurement of CFCs in air samples from the stratosphere |
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The recovery of refrigerant is necessary to |
All of the above maintain adequate supplies for service calls after the production bans prevent the venting of refrigerants to the atmosphere prevent stratospheric ozone depletion |
|
an example of an HFC refrigerant is |
R-410a |
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A compound pressure gauge typically used on the low side of the system measures pressures in |
PSIG and inches of mercury |
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________Refers to the process of cleaning refrigerant by-Oil separation and single or multiple passes through filter driers which reduce moisture and acidity? |
Recycling |
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The high pressure gauge on service manifold set has a continuous scale usually calibrated to read from |
0 - 500 PSI |
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______Is the process that returns refrigerant to new product specification and that requires chemical analysis? |
Reclaim |
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A cylinder with a gray body and a yellow top indicates that the cylinder is designed to hold |
Recovered refrigerant |
|
HCFC refrigerants |
Are less harmful to stratospheric Ozone than CFCs |
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Which type of refrigerant is the most harmful to stratospheric Ozone? |
Refrigerants containing bromine |
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According to the EPA a _____ leak detection method is considered to be the most effective for locating the general area of a small leak |
electronic or ultrasonic testers |
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Long hoses between the unit and the recovery machine should not be used because they cause: |
All of the above excessive pressure drop increase recovery time increased emissions |
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Recovery equipment that relies upon the compressor in the system would be considered: |
System dependent |
|
A hermetic compressor must never be operated when |
There is a dehydration vacuum in the system |
|
Self contained recovery devices |
Can capture liquid and or vapor refrigerant without the assistance of components in the air conditioning or Refrigeration equipment |
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System charged with R-410A should be leak checked with: |
Pressurized nitrogen |
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R-410A is not a typical blended refrigerant because: |
All of the above are true |
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A ternary refrigerant blend is a ______ part mixture. |
Three part |
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In a refrigerant system high pressure vapor is converted to high pressure liquid in the: |
Condenser |
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Which of the following is an approved "drop-in" service replacement for R-12? |
According to the EPA there are no drop-in replacements |
|
The proper method of discarding a disposable refrigerant cylinder is to: |
Assure that all is recovered and that the cylinder is rendered useless then recycle the metal |
|
CFC refrigerants are so named because they contain the elements |
Chlorine fluorine carbon |
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Before you dispose of any system containing a refrigerant you must: |
Recover the refrigerant |
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According to EPA regulations which of the following procedures is not an approved technique for system cleanup after a burnout? |
Flushing with liquid refrigerant to clean tubing |
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When using nitrogen to pressurize a system you should always |
Charge through a pressure regulator |
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What effects can ozone depletion have on the environment? |
All of the above reduced crop yields reduced marine life increased ground level ozone |
|
Non Azeotropic refrigerant leak from a system |
In uneven amounts due to different Vapor pressures |
|
An example of an HCFC refrigerant is |
R-22 |
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Which chemicals are controlled by the Montreal protocol? |
All of the above chlorofluorocarbons Hydrochlorofluorocarbons halons |
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Systems charged with R-134a should be leak checked with |
Pressurized nitrogen |
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When is the system the hoses should be |
Equal to or larger than vacuum pump Inlet connection |
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It has been illegal to vent substitutes for CFC and HCFC refrigerants since |
November 1995 |
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Never use oxygen or compressed air to pressurize a system because |
Oxygen and compressed air do not mix with refrigerant |
|
Refrigerant cylinder should always be |
Free of rust damage color coded to indicate the content and secure all the above |
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Even though R-22 is considered non toxic it: |
Can cause asphyxia |
|
A system is dehydrated to: |
Remove water and water vapor |
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According to the EPA of the refrigerants listed below which type of refrigerant will not contribute to global warming? |
They all contribute to global warming |
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The type of oil that is most commonly used in stationary air conditioning applications with HFC -410A refrigerant is |
Ester oil |
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Technicians receiving a passing grade on the type 2 medium pressure high pressure and very high pressure exam are certified to recover refrigerant during the maintenance service or repair of a medium and high pressure equipment and very high pressure refrigerants including |
With type 2 certification you are certified for all very high pressure refrigerant including CFC 13 and CFC 503 |
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Personal protective equipment gloves safety glasses Safety Shoes should always be worn when |
Handling and filling refrigerant cylinders |
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Refrigerant Vapors or Mist should not be inhaled because |
They may cause heart irregularities and or unconsciousness |
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Of the items listed below which is are violation of the clean air act? |
All of the above falsifying or failing to keep required records failing to reach required evacuation levels before opening or disposing of appliances knowingly releasing CFC HCFC refrigerants or their substitute while repairing appliances |
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HFC refrigerants contain |
Hydrogen fluorine carbon |
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Which refrigerant contained an HCFC? |
R-22 |
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Recovery equipment that relies upon the pressure of the refrigerant in the appliance would be considered |
System dependent |
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Refrigerant entering the compressor under normal operating conditions is a |
Low-pressure vapor |
|
It is necessary to place a refrigerant label on |
A refrigerant cylinder which is being returned for reclaiming |
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Which refrigerant contains a CFC? |
R 500 |
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Used ______ to remove ice from a sight glass |
An alcohol spray |
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According to the EPA an oil sample should be taken for which of the following reasons |
The system had a leak or a major component failure |
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The EPA requires the installation of a service aperture or process stub on all appliances using a Class 1 or Class 2 substance as a refrigerant. The main purpose of this requirement is to make it easier to |
Recover refrigerant |
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Recycling and Recovery equipment intended for use with air conditioning and Refrigeration equipment except for small appliances must be tested under |
ARI-740 |
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Refrigerant entering the compressor of a refrigeration system is a |
Superheated vapor |
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What is being done in the US to stop damage to the stratospheric ozone layer |
Capturing and ultimately eliminating use of chlorofluorocarbons |
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The type of oil that is most commonly used in stationary Refrigeration applications with HFC -134a refrigerant is |
Ester oil |
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The term used to describe the fact that a refrigerant blend has a range of boiling or condensing points at a constant pressure is |
Temperature Glide |
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Which refrigerant contains a CFC? |
R 12 |
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Under epa's regulations what standard must reclaimed refrigerant meet before it can be resold |
ARI 700 |
|
An example of a HFC refrigerant is |
R-134a |
|
It is illegal to |
Knowingly releasing refrigerant during the service maintenance repair or disposal of appliances with the exception of de minimis releases |
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Which type of refrigerant is the most harmful to stratospheric Ozone |
CFC |
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Refrigerant that enters the expansion or throttling device also known as the metering device is a |
Liquid |
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Which of the following statements would be considered good service practices for conserving refrigerant? |
All of the above recover recycle refrigerant keep system tight find and repair leaks |
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Under the EPA safe disposal requirements the person responsible for making sure that the refrigerant has been removed from household refrigerators before they are disposed of is the |
Final person in the disposal chain |
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Which refrigerant listed below is a low pressure refrigerant under EPA Refrigerant recycling regulations |
R-123 |
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When moisture exits in an operating system which of the following is most likely to occur |
Acid will form |
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Which of the following is a very high pressure refrigerant under epa's refrigerant recycling regulations |
R-13 |
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When using nitrogen to pressurize a system you should |
Only charged with nitrogen vapor |
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Of the refrigerants listed below which has the lowest ozone depletion potential |
R-134a |
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When dealing with small systems how many different refrigerants may be recovered into the same cylinder |
Only one |
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When operating refrigerant recovery or recycling equipment the following precautions should always be followed |
All of the above wear safety glasses protective gloves follow all safety precautions for the equipment |
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Other refrigerants listed below which type of refrigerant will not damage stratospheric ozone |
HFCs |
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When evacuating a system the hoses should be |
A short in length and as long in diameter as possible |
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Refrigerant leaves the condenser of an operating system as a |
High pressure liquid |
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Is corrosion is found within the body of a relief valve the valve must be |
Replaced |
|
The Clean Air Act |
All the above set a schedule for the phase-out of CFC HCFC production prohibits venting of refrigerants authorizes the EPA to set standards for Recovery of refrigerant |
|
Measuring the system's final vacuum is always done with |
The system isolated in the vacuum pump off |
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A refillable refrigerant cylinder must never be filled to more than _____ of its capacity by weight |
0.8 |
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Of the refrigerants listed below which refrigerants type have the highest depletion potential |
CFCs |
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This chemical was found in the upper Stratosphere and that indicates that the ozone layer is being destroyed |
Chlorine monoxide |
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What factor affects the speed of evacuation |
All of the above the size of the equipment being evacuated the ambient temperature amount of moisture in system |
|
HCFC refrigerants contain |
Hydrogen chlorine fluorine carbon |
|
When a system will not hold a vacuum after it has been evacuated then |
The system may be leaking |
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All recovery equipment currently being made is required to have |
An EPA approved certification label |
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The color code for Approved refrigerant recovery cylinders is |
Yellow tops and gray bodies |
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When can you use a disposable cylinder to recover refrigerant |
Never |
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Which of the following is a high pressure refrigerant under epa's refrigerant recycling regulations |
R-22 |
|
After refrigerant liquid transfer between recovery unit and the system being emptied you need to avoid trapping |
Liquid refrigerant between service valves |
|
You can determine safe pressure for leak testing a system from the |
Low side test pressure data plate value |
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If a technician has a system where some R502 was added to an R22 system the technician should |
Recover all refrigerant into a separate tank |
|
Ozone in the stratosphere above the Earth consists of |
Molecules of 3 oxygen atoms |
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The size capacity of the vacuum pump and the size of the suction line used will determine |
The length of dehydration time |
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According to the EPA when dealing with customer complaints regarding additional costs due to refrigerant recovery efforts the technician should |
All of the above |
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State and local governments can make state laws that |
Follow the Clean Air Act EPA regulations contain stricter regulations than the Clean Air Act EPA regulations |
|
If an oil hygroscopic it means that it |
Readily absorbs moisture |
|
When dehydrating a system the system can be heated to |
Decrease the dehydration time |
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Synthetic lubricant presently used with ternary blends containing HCFCs is |
Alkylbenzene |
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Ozone depletion in the stratosphere is what type of problem |
Global |
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Typical three port three hose manifold gauge the center Port is used for |
Recovery evacuation and charging |
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Ester based oils can be mixed with |
No other oils |
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CFCs will no longer be manufactured or imported into the United States after |
1995 |
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Which type of refrigerants are chlorine free |
HFCs |
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Refrigerant recovery during low ambient temperatures will |
Slow the recovery process |
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______ is the process of removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in any way |
Recovering |
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Containers designated refillable by DOT are used for transporting recovered pressurize refrigerant |
To meet safety requirements |