Hvac

Front 1

R-134 a refrigerant charged systems should be leak checked with:

Back 1

Pressurized nitrogen

Front 2

The oils that will be employed with most of the HFC-134a refrigeration applications are:

Back 2

Esters

Front 3

The ozone layer protects the earth from:

Back 3

Ultraviolet radiation from the sun

Front 4

Disposing of disposable cylinders is accomplished by:

Back 4

Assuring that all refrigerant is recovered and that all the cylinders are rendered useless then recycling the metal.

Front 5

Recovery equipment that relies upon the compressor in the appliance and/or the pressure of the refrigerant in the appliance would be considered:

Back 5

System-dependent

Front 6

What is the strongest evidence that CFC's are in the stratosphere?

Back 6

Measurement of CFC's in air samples from the stratosphere

Front 7

Which of the following CFC or HCFC refrigerant releases is considered a violation of the prohibition on venting:

Back 7

Release of mixtures of nitrogen and refrigerant that results from adding nitrogen to a fully charged appliance to leak-check the appliance

Front 8

Self-contained recovery devices:

Back 8

Can capture liquid and/or vapor refrigerant without the assistance of components in the air-conditioning or refrigeration equipment

Front 9

Systems to be charged with R-134a should be leak checked with:

Back 9

Pressurized nitrogen

Front 10

Violation of the Clean Air Act, including the knowing release of refrigerant during the maintenance, service, repair or disposal of appliances, can result in fines up to:

Back 10

$25,000 per day per violation

Front 11

EPA may require technicians to demonstrate their ability to perform proper procedures for recovering and/or recycling refrigerant. Failure to demonstrate or failure to properly use the equipment may result in:

Back 11

Revocation of the technician's certification

Front 12

EPA regulations require the installation of a service aperture or process stub on all appliances using a class I or class II substance as a refrigerant. The main purpose of this requirement is to make it easier to:

Back 12

Recover refrigerant

Front 13

Which of the following is a "high-pressure refrigerant” under EPA's refrigerant recycling regulations:

Back 13

R-12

Front 14

Ozone depletion in the stratosphere is what type of problem?

Back 14

Global

Front 15

The term used to describe the fact that a refrigerant blend has a range of boiling or condensing points at a constant temperature is:

Back 15

Temperature glide

Front 16

Vacuum line (hoses) should be:

Back 16

Equal to or larger than pump intake connection

Front 17

Which of the following is a "low-pressure refrigerant” under EPA's refrigerant recycling regulations:

Back 17

R-123

Front 18

Ozone depletion potential, or "ODP”, is:

Back 18

A measurement of CFCs' and HCFCs' ability to destroy ozone

Front 19

All recovery equipment now manufactured is required to have

Back 19

An EPA approved certification label

Front 20

A refrigerant oil that is hygroscopic:

Back 20

Readily absorbs moisture

Front 21

An example of an HFC refrigerant is:

Back 21

R-134a

Front 22

The smallest container in which refrigerants may be sold to Section 608 certified technicians is:

Back 22

20 lb.

Front 23

Recovery equipment that relies upon the compressor in the appliance and/or the pressure of the refrigerant in the appliance would be considered:

Back 23

System-dependent

Front 24

Hydrochlorofluorocarbon (HCFC) refrigerants contain:

Back 24

Hydrogen, chlorine, fluorine and carbon

Front 25

When pressurizing a refrigeration system with nitrogen, what rule should you always follow?

Back 25

Charge through a pressure regulator

Front 26

Blended refrigerants leak from a system:

Back 26

In uneven amounts due to different vapor pressures

Front 27

For accurate readings during evacuation the system vacuum gauge should be connected:

Back 27

As far from the vacuum pump as possible

Front 28

Which of the following is not an approved technique of system cleanup after a burnout?

Back 28

Flushing with liquid refrigerant to clean field tubing

Front 29

Equipment covered by EPA regulations include:

Back 29

All air-conditioning and refrigeration equipment containing and using CFC and HCFC refrigerants

Front 30

The synthetic lubricant presently used with ternary blends containing HCFCs is:

Back 30

Alkylbenzene

Front 31

An example of a CFC refrigerant is:

Back 31

R-12

Front 32

The piping connection to the vacuum pump should be:

Back 32

As short in length and as large in diameter as possible

Front 33

When recovering refrigerant, it is important not to mix different refrigerants in the same container because:

Back 33

The mixture may be impossible to reclaim

Front 34

Which of the following gases help form the earth's protective shield?

Back 34

Stratospheric Ozone

Front 35

It is illegal to:

Back 35

Knowingly release CFC or HCFC refrigerants and their substitutes during the service,maintenance, repair or disposal of appliances, with the exceptiion of de minimis releases

Front 36

What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine?

Back 36

CFCs neither dissolve in water nor break down into compounds that dissolve in water, so they do not rain out of the atmosphere

Front 37

Under the "safe disposal requirements”, who is responsible for the ensuring that refrigerant has been removed from household refrigerators before they are disposed of?

Back 37

The final person in the disposal chain

Front 38

Which of the following human health effects could result from an increase in ultraviolet radiation?

Back 38

An increase in the number of cataracts

Front 39

What is a ternary blend refrigerant?

Back 39

A three-part mixture

Front 40

Removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in any way defines:

Back 40

Recovering

Front 41

Whenever working with any solvents, chemicals and refrigerants, the technician should review:

Back 41

Material safety data sheets

Front 42

Reusable containers for refrigerants that are under high pressure (above 15psig) at normal ambient temperature must be hydrostatically tested and date stamped every:

Back 42

5 years

Front 43

Manufactures often color code the exterior of gauges. On a typical gauge manifold set, the high pressure gauge is color-coded:

Back 43

Red

Front 44

The component which changes a low pressure vapor to a high pressure vapor is the:

Back 44

Compressor

Front 45

Upon completion of refrigerant liquid transfer between recovery unit and the refrigeration system, you should guard against trapping:

Back 45

Liquid refrigerant between service valves

Front 46

The reason for dehydrating a refrigeration system is:

Back 46

To remove water and water vapor

Front 47

Which type of refrigerant is the most harmful to stratospheric ozone?

Back 47

CFC

Front 48

The capacity of a vacuum pump and its suction line size will determine:

Back 48

The length of dehydration time

Front 49

Whenever dry nitrogen from a portable cylinder is used in service and installation practice, what Item is of most importance in consideration of safety?

Back 49

A relief valve is inserted in the downstream line from the pressure regulator

Front 50

Approved refrigerant recovery cylinders can be identified by which color code?

Back 50

Yellow tops and gray bodies

Front 51

Evacuation of a system is a suggested method of:

Back 51

Dehydration

Front 52

What is being done in the U.S. to stop damage to the stratospheric ozone layer?

Back 52

Capturing and ultimately eliminating use of chlorofluorocarbons

Front 53

Refrigerant will migrate to a compressor's crankcase because of a difference in _________ between the oil and refrigerant:

Back 53

Vapor pressure

Front 54

The state of the refrigerant entering the compressor of the refrigeration system is:

Back 54

Low-pressure vapor

Front 55

Refrigerant entering the metering or expansion device of a refrigeration system is a:

Back 55

Liquid