AC system

oscillator

All automotive A/C systems contain the following components except: -compressor -condenser -evaporator -oscillator

all of these

Choose the factors that affect "heat load". -humidity -ambient temperature -sun load -all of these

restriction

High pressure liquid through a ________. -compressor -condenser -restriction -none of these

both a and b

List the types of A/C lubricating oil currently in use by General Motors. -525-viscosity mineral oil -PAG (Polyalkaline Glycol) -both a and b -neither a nor b

fluorocarbon

Refrigerant R-134a is a? -fluorocarbon -hydrocarbon -H3C607 molecule -micro carbon

technician b only

Technician A says refrigerant R-134a is less efficient then R-12 and requires a smaller condenser. Technician B says refrigerant R-134a is not interchangeable with R-12. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician b only

Technician A says when a compressor is removed for servicing the amount of PAG (Polyalkylen Glycol) remaining in the compressor should be retained for future use. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says you should never fill a refrigerant tank to more than 60% of its gross weight rating. Technician B says you should never fill a refrigerant tank to more than 90% of its gross weight rating. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

engine

The Compressor is driven by the _______ on most cars. -engine -battery -driver -gasoline

both a and b

The automotive industry, as a contributor to the release of CFCs into the atmosphere, is taking important steps to avoid further damage to the ozone. Name two steps concerning A/C refrigerant the automotive industry is taking in the clean air effect. -reclaim and recycle R-12 refrigerant -use a non-CFC refrigerant (R-134a) -both a and b -neither a nor b

evaporator, condenser

The blower motor affects ________ heat transfer in the same way that the coolant fan affects _______ heat transfer. -evaporator, condenser -evaporator, heater core -condenser, radiator -none of these

lt. blue

The color of the R-12 charging tank is white. The color of the R-134a charging tank is _____? -dk. yellow -lf. green -lt. blue -red

high pressure vapor

The condenser is used to liquefy the hot, ________ it receives from the compressor. -high pressure vapor -low pressure vapor -medium pressure -none of these

heat

The condenser transfers ________ to the outside air. -heat -water -pollen -dust

condenser

The low pressure side of the A/C system includes all of the following components except: -evaporator -accumulator -compressor inlet -condenser

low pressure liquid

The orifice tube meters the refrigerant into the evaporator as a ________? -low pressure liquid -low pressure vapor -high pressure liquid -high pressure vapor

supcooling

The process of removing heat from the refrigerant after condensation is known as -super cooling -subcooling -after cooling -none of these

both a and b are correct

The purpose of the Air Conditioning System is to: -remove heat from the air entering the passenger compartment. -remove moisture from the air entering the passenger compartment. -both a and b are correct -neither a nor b is correct

true

True or false: pressure can change the boiling point of refrigerants.

true

True or false: the behavior of heat is branch of physics known as thermodynamics.

true

True or false: the two main types of oil used with R-134a are PAG and Ester oil.

evaporator

an orifice tube is typically located in the refrigerant line between the condenser outlet and the _______ inlet. -compressor -accumulator -evaporator -filter-dryer

low pressure vapor to high pressure vapor

the compressor changes: -low pressure vapor to high pressure vapor -low pressure vapor to high pressure liquid -high pressure liquid to high pressure vapor -low pressure liquid to low pressure vapor

heat moisture pollen dust

the evaporator is a heat exchanges that removes?Choose all that apply. -heat -moisture -pollen -dust

all of these

A TXV or thermostatic expansion valve can perform the following functions: -throttling -modulation -metering -all of these

service valve

A ________ is typically located near the top of the accumulator-dryer. -heater -oil-bleed hole -service valve -blow-off valve

all the above

A thermostatic expansion value: -regulates refrigerant flow -drops pressure -changes high pressure liquid to low pressure -all the above

evacuated

All disposable refrigerant containers should be _______ before being discarded in the trash. -compressed -filled -crushed -evacuated

pressure cycling switch, PCM

Control of the compressor clutch can either by directly controlled by the _______ or by the _______. -pressure cycling switch, PCM -temperature cycling switch, PCM -both a and b -none of these

pressure cycling switch

Fixed displacement compressors are started and stopped automatically by an electromagnetic clutch and an electric switch, called the ________. -pressure cycling switch -temperature cycling switch -both a and b -neither a nor b

cover the opening with tape

How can you prevent contamination of the refrigerant system once the valve is removed? -fill the system with water -cover the opening with tape -leave some refrigerant in the system -leave open

from the driver door module through class 2 communication

How does the HVAC control module receive the personalization information? -from the Powertrain Control Module through class 2 communication -from the Body Control Module through class 2 communication -from the Rear Control Module through class 2 communication -from the driver door module through class 2 communication

evaporator

If a thermostatic switch or sensor is used to control the compressor clutch, where is the sensor's element located? -condenser -compressor -evaporator -radiator

restricted, high

If airflow across the condenser is ______ or _______ discharge pressure will result. -restricted, high -restricted, low -excessive, high -blocked, low

cold, freeze

If the evaporator surfaces are too ______, the moisture on the fins will not drain off as water. Instead it will ______? -hot, freeze -cold, dry -cold, freeze -wet, freeze

all of these

In 1987 the United States joined with the European Economic Community and the World Community of Nations to ratify the Montreal Protocol on Substances that Deplete the Ozone Layer. This landmark agreement sets limits on the production of ______ chemicals. -ozone-depleting -ozone-forming -oxygen-depleting -oxygen-forming

condensed

In the condenser refrigerant is: -condensed -boiled -converted to H20 -not affected

low pressure vapor

In the evaporator as heat is absorbed, the refrigerant changes to: -low pressure liquid -low pressure vapor -high pressure liquid -high pressure vapor

passenger compartment

In the recirculating air conditioning mode, most of the air entering the blower motor is taken from: -passenger compartment -outside the vehicle -engine compartment -none of the above

all of these

List some ways a condenser may malfunction. -leaks -refrigerant flow restriction -restricted air flow -all of these

all of the these

R-12 and R-134a refrigerants are not interchangeable. The service technician should be aware that refrigerant charge labels maybe located in several locations. List the locations. -top of blower housing -front fan shroud -top of accumulator -all of the these

chlorofluorocarbon

R-12 refrigerant is categorized as a: -hydrocarbon -chlorofluorocarbon -polycarbon -all of the above

both a and b are correct

Refrigerant R-134a can be a? -vapor -liquid -both a and b are correct -neither a nor b is correct

technician b only

Technician A says "heat load" is the amount of heat that must be removed. Technician B says "heat load" is the amount of heat absorbed by the refrigerant. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says Chlorinated Fluorocarbons (CFC) destroys the ozone in the stratosphere through chemical action. Technician B says while oxygen is essential to life, ozone is harmful when breathed and contributes to smog. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says Document J1989 establishes guidelines for the use of recovery/recycling equipment when servicing A/C equipment. Technician B says Document J1990 concerns equipment standards. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says General Motors currently uses a variable displacement compressor. Technician B says by varying displacement and not on time, the compressor can keep a more equal load on the engine. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says R-12 and R-134a are colorless in both the liquid and gaseous states. Technician B says always observe manufacturers safety precautions when handling A/C refrigerant. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says a refrigerant device is necessary in automotive A/C systems in order to build pressure and maintain the refrigerant cycle. Technician B says that air conditioning systems using R-134a do not need a metering device. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says a throttle position of 100% will cause the A/C compressor to turn off. Technician B says very cold intake air temperature (IAT) will cause the A/C compressor not to operate. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says as refrigerant vaporizes it expands. Technician B says the refrigerant is drawn into the compressor and the cycle repeats. Which Technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says certain applications use a pressure sensor located in the low side of the refrigeration system. Technician B says certain applications use a pressure sensor located in the high side of the refrigeration system. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician b only

Technician A says compressor oil should be checked always. Technician B says compressor oil should be only when there is evidence of a major loss of system oil. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says cycling clutch compressors are controlled by controlled by cycling on and off according to the pressure or temperature in the low side of the refrigeration system. Technician B says that cycling clutch compressors are primarily controlled by cycling then on and off according to the high side pressure of the refrigeration system. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says effective January 1, 1992, no person will repair or service automotive A/C systems unless properly trained and certified. Technician B says technicians must use approved refrigerant recycling equipment as of January 1, 1992. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says high-pressure refrigerant flows through the orifice tube and becomes the low-pressure refrigerant before entering the Evaporator. Technician B says high-pressure refrigerant flows through the orifice tube and remains high-pressure as it enters the evaporator. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says orifice tube failure is usually indicated by low-discharge pressure and insufficient evaporator cooling. Technician B says that the orfice tube should be matched to the air conditioning system. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says pressure cycling switch location will vary but it will always be located on the low-pressure side of the A/C system. Technician B says says the pressure cycling switch will always be located on the high-pressure side of the A/C system. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

neither a nor b

Technician A says recirculation mode can only be used in the automatic setting. Technician B says recirculation mode can only be used in the manual operation. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician b only

Technician A says that an engine that is overheating will cause the A/C compressor not to operate. Technician B says ignition voltage below 9 volts will cause the A/C compressor not to operate. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician b only

Technician A says that during A/C system operation, refrigerant vapor flows from the metering device into the evaporator. Technician B says during A/C operation, liquid refrigerant flows from the metering device into the evaporator. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says that power is provided to the blower motor from the control processor. Technician B says the ground to the blower motor from the control processor. Which Technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says that the hot high-pressure refrigerant vapor passes through the condenser coils and changes to a warm high-pressure liquid. Technician B says that cold low-pressure liquid passes through the condenser and changes to a vapor. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says the desiccant located inside the receiver-dryer absorbs any moisture that might enter the system. Technician B says the features offered in the receiver-dryer prevent obstruction to the valves or damage to the compressor. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says the desiccant located inside the receiver-dryer absorbs any moisture that might enter the system. Technician B says the receiver-dryer can be considered as a storage tank for the liquid refrigerant from the compressor. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says the efficiency and service life of an air conditioning system depends upon the chemical ability in the refrigeration system. Technician B says when contaminants such as air, dirt and moisture enter the refrigeration system, they alter the stability of the refrigerant and refrigerant oil. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says the orifice tube is one of the drivding points between the high-pressure and low-pressure sides of the refrigerant system. Technician B says the orifice tube, with its mesh screen and orficie, provides a restriction to the high-pressure refrigerant in the liquid line. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says the receiver-dryer can be considered as a storage tank for the liquid refrigerant from the condenser. Technician B says the receiver-dryer can be considered as a storage tank for the liquid refrigerant from the compressor. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician b only

Technician A says the remote bulb is clamped to the high-pressure vapor line just beyond the evaporator inlet. Technician B says the remote bulb is filled with highly expansive gas. Which technician is correct? Technician A says orifice tube failure is usually indicated by low-discharge pressure and insufficient evaporator cooling. Technician B says that the orfice tube should be matched to the air conditioning system. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

both a and b

Technician A says thermistors are used in some A/C systems to control evaporator temperatures. Technician B says a thermistor is a sensor that converts evaporative temperature into a resistance value. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

technician a only

Technician A says thermostatic expansion valve failure is indicated by the same symptoms as Orifice Tube failure. Technician B says thermostatic expansion valve failure is indicated by the same symptoms as evaporator failure. Which technician is correct? Technician A says orifice tube failure is usually indicated by low-discharge pressure and insufficient evaporator cooling. Technician B says that the orfice tube should be matched to the air conditioning system. Which technician is correct? -technician a only -technician b only -both a and b -neither a nor b

the outside air

The Refrigeration System then releases the absorbed heat to: -the outside air -the inside air -the engine coolant -none of these

all of the above

The Society of Automotive Engineers has established guidelines concerning allowable leak rate in automotive refrigerant systems. Which of the following specifications applies to the established guidelines for leak detectors? -must be capable of detecting a 0.5 ounce per year leak of R-134a -must detect the leak when held 0.25 inches away from the leak -must clearly alert the operator of the detection -all of the above

both a and b

The TXV may use an _______ equalizer. -internal -external -both a and b -neither a nor b

10 btu

The amount of heat required to raise the temperature of 1 pound of water by 10F is: -1 btu -10 btu -20 btu -100 btu

high pressure vapor and liquid

The condenser outside the passenger compartment is: -high pressure vapor and liquid -low pressure vapor and liquid -high pressure vapor only -high pressure liquid only

dehumidifies

The evaporator removes heat and _____ the airstream entering the passenger compartment? -humidifies -dehumidifies -deodorizes -vaporizes

excessive head levels

The high pressure cutoff switch protects the compressor from: -low refrigerant levels -low lubricant levels -excessive head pressure -excessive vacuum

high, low

The refrigerant system is divided into two portions: a _______ pressure side and a _____ pressure side. -high, low -medium, high -medium, low -high, very high

equalizer

To compensate for pressure/temperature differentials at the evaporator outlet, a/an _______ modulates between actual pressure and measured temperature. -equalizer -tranquilizer -modularizer -none of these

false

True or false: BTUs are a measurement of pressure.

false

True or false: heat always moves from cold to hot.

true

True or false: latent heat is the amount of heat necessary to change a substance from one state to another.

heat air cool air remove humidity reduce windshield fogging

What are the main jobs of a HVAC System? -heat air -cool air -remove humidity -reduce windshield fogging

class 2 device

What type device is the HVAC control module? -parallel device -class 2 device -class 4 device -none of these

cold air

When an evaporator is defective, trouble often shows up as an inadequate supply of ? -warm air -cold air -moist air -none of these

the amount of oil in the new compressor must be balanced to the amount drained from the old compressor.

When installing a new compressor, the refrigerant oil must be balanced. What does that mean? -the amount of oil in the new compressor should be less than the amount oil drain from the old compressor. -the amount of oil in the new compressor should be more then the amount of oil drain from the old compressor -the amount of oil in the new compressor must be balanced to the amount drained from the old compressor. -the amount of oil in the new compressor should be equal to the amount of oil specified as the total system capacity in the service manual.

both a and b

When performing a retrofit service on an air conditioning equipped with a pressure relief valve, what additional device must be installed? -low pressure cut out switch -high pressure cut out switch -both a and b -neither a nor b

replace with new

When the new valve is installed, what is recommended that you do with the sealing washers? -re-use them -clean, then re-use -replace with new -slightly sand, then re-use

a compressor

Which of the following components is not a heat exchanger? -an evaporator -a radiator -a condenser -a compressor

both a and b are correct

the Evaporator inside the passenger compartment is: -low pressure vapor -low pressure liquid -both a and b are correct -neither a nor b is correct