Hvac

Front 1

One instance when personal protective equipment (gloves, safety glasses, safety shoes, etc.) should be worn is when:

Back 1

handling and filling refrigerant cylinders

Front 2

When scrapping a disposable cylinder, the internal cylinder pressure should be reduced to at least:

Back 2

0 psig

Front 3

The center port on a three-port manifold is used for:

Back 3

Recovery, evacuate and charging

Front 4

An oil sample should be taken for which of the following reasons?

Back 4

The unit has had a leak or a major component failure

Front 5

Long hoses between the unit and the recovery machine should be avoided to prevent:

Back 5

Excessive pressure drop

Increased recovery time

Increased emissions

Front 6

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

Back 6

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

Front 7

During servicing of a refrigeration system containing R-12, the refrigerant must be:

Back 7

Recovered

Front 8

A system is said to be dehydrated when:

Back 8

The vacuum indicator shows you have reached and held the required finished vacuum

Front 9

Which of the following is/are violation(s) of the Clean Air Act?

Back 9

Falsifying or failing to keep required records

Failing to reach required evacuation levels before opening or disposing of appliances

Knowingly releasing CFC or HCFC refrigerants or their substitutes while repairing of appliances

Front 10

How many different refrigerants may be recovered into the same cylinder?

Back 10

Only one

Front 11

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 refrigerant into the atmosphere?

Back 11

$10,000

Front 12

Before you dispose of any appliance containing a CFC or HCFC refrigerant, you must:

Back 12

Recover the refrigerant

Front 13

What is one of the most serious results of damage to the ozone layer?

Back 13

Increases in human skin cancer

Front 14

Which compounds have the highest ozone depletion potential (ODP)?

Back 14

CFCs

Front 15

During dehydration of a refrigeration system, the system may be heated to:

Back 15

Decease dehydration time

Front 16

Some state and local governments may establish laws that:

Back 16

Follow the Clean Air Act/EPA regulations

Contain stricter regulations than the Clean Air Act/EPA regulations

Front 17

Which of the following refrigerants will not damage stratospheric ozone?

Back 17

HFCs

Front 18

All devices used for refrigerant recovery must:

Back 18

Meet EPA standard

Front 19

What chemical found in the upper stratosphere indicates that the ozone layer is being destroyed?

Back 19

Chlorine monoxide

Front 20

What effect can ozone depletion have on the environment

Back 20

Reduced crop yields

Reduced marine life

Increased ground-level ozone

Front 21

What is unique about an azeotropic refrigerant mixture?

Back 21

It is a mixture that acts like a single component refrigerant over its entire range

Front 22

Ester based oils can be mixed with:

Back 22

No other oils

Front 23

Refrigerant entering the compressor of a refrigerant system is a:

Back 23

Superheated vapor

Front 24

The high pressure gauge on service manifold sets has a continuous scale, usually calibrated to read from:

Back 24

0 to 500 psi

Front 25

Which of the following leak detection methods is considered to be the most effective for locating the general area of a small leak?

Back 25

Electronic or ultrasonic tester

Front 26

HCFC refrigerants are:

Back 26

Less harmful to stratospheric ozone than CFCs

Front 27

To remove ice from sight glasses or viewing glasses, use:

Back 27

An alcohol spray

Front 28

A refrigerant cylinder that has a gray body and a yellow top indicates that the cylinder is designedto hold:

Back 28

Recovered refrigerant

Front 29

When transporting cylinders containing used refrigerant, DOT requires that you:

Back 29

Attach DOT classification tags

Front 30

Chlorofluorocarbon (CFC) refrigerants are so named because they contain the elements:

Back 30

Chlorine, fluorine and carbon

Front 31

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

Back 31

Capturing and ultimately eliminating use of chlorofluorocarbons

Front 32

While servicing a system, the technician discovers that some R-502 was added to an R-22 system.The technician should:

Back 32

Recover the refrigerant into a separate tank

Front 33

Ozone in the stratosphere above the earth consists of:

Back 33

Molecules containing 3 oxygen atoms

Front 34

A refillable refrigerant cylinder must not be filled above ______ percent of its capacity by weight:

Back 34

80

Front 35

How should refrigerant cylinders be positioned when they are shipped?

Back 35

Upright

Front 36

Which refrigerant contains a CFC?

Back 36

R-500

Front 37

Hydrofluorocarbon (HFC) refrigerants contain:

Back 37

Hydrogen, fluorine and carbon

Front 38

A compound pressure gauge for the low side of the system measures pressure in:

Back 38

PSIG and in. of mercury

Front 39

Manufacturers often color code the exterior of gauges. On a typical gauge manifold set, thelow pressure gauge is color-coded

Back 39

Blue

Front 40

Recovery during low ambient temperatures will:

Back 40

Slow the recovery process

Front 41

Which atom of the CFC molecule causes ozone depletion?

Back 41

Chlorine

Front 42

Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) have which of the following in common?

Back 42

They must be recovered before opening or disposing of appliances

Front 43

The Montreal Protocol is:

Back 43

A treaty among nations that control production of chlorofluorocarbons and hydrochlorofluorocarbons

Front 44

Each chlorine atom in the stratosphere can destroy _____ ozone molecules:

Back 44

100,000

Front 45

Cooling occurs in a direct-expansion vapor-compression refrigeration system when:

Back 45

Refrigerant liquid turns to a vapor

Front 46

A hermetic compressor must never be operated when:

Back 46

There is a dehydration vacuum in the system

Front 47

If a system will not hold a vacuum after it has been evacuated, then:

Back 47

The system may be leaking

Front 48

Which refrigerant is an HCFC?

Back 48

R-22

Front 49

Refrigerant vapors or mist in high concentrations should not be inhaled, since:

Back 49

They may cause heart irregularities unconsciousness

Front 50

Why must containers designated "refillable” by DOT be used for transporting recovered pressurized refrigerant?

Back 50

To meet safety requirements

Front 51

An example of an HCFC refrigerant is:

Back 51

R-22

Front 52

When corrosion builds up is found within the body of a relief valve, the valve must be:

Back 52

Replaced

Front 53

Disposable refrigerant containers are used for what type of refrigerant?

Back 53

. Virgin

Front 54

A refrigerant label is placed on a:

Back 54

Refrigerant cylinder to be returned for reclaiming

Front 55

Which type of refrigerant is most harmful to stratospheric ozone?

Back 55

. CFC

Front 56

Measuring a final system vacuum is done with the:

Back 56

System isolated and vacuum pump turned off

Front 57

Blended refrigerants should be charged:

Back 57

As a liquid

Front 58

Which work applies to the process that returns refrigerant to new-product specifications and that requires chemical analysis?

Back 58

Reclaim

Front 59

Which refrigerant is a chlorine-free refrigerant?

Back 59

HFC-134a

Front 60

The state of the refrigerant leaving the condenser of a refrigeration system is:

Back 60

High-pressure liquid

Front 61

The component of a refrigeration system which changes a high-pressure vapor to a high-pressureliquid is the:

Back 61

Condenser

Front 62

You have to leak-check a unit which has lost a complete charge. Which gas(es) would cause the LEAST damage to the environment?

Back 62

Dry Nitrogen