Certification Test for A/C and Heating

C. a clogged evaporator case drain

A complaint concerning water on the front floor carpeting even in dry weather could be caused by _____ A. evaporator flooding B. a saturated desiccant bag C. a clogged evaporator case drain D. all answers are correct

B. insufficient clearance between the rotor pulley and the armature plate

A compressor clutch that chatters when the A/C is either on or off could be caused by _____. A. defective compressor bearings B. insufficient clearance between the rotor pulley and the armature plate C. low refrigerant oil level D. excessive drive belt tension

At the bottom of the condenser

A subcooler is located _____________________.

R-12

Before 1994, most manufacturers used __________ as a refrigerant.

D. identified

Before recovering refrigerant, the refrigerant must be _____. A. heated C. filtered B. measured D. identified

A. on the low side as a vapor

Normally the A/C system is charged _____ with the engine running. A. on the low side as a vapor B. on the low side as a liquid C. on the high side as a vapor D. on the high side as a liquid

B. B only

Technician A says all the refrigerant oil in the A/C system is contained inside the compressor. Technician B says the oil circulates throughout the entire A/C system and at any given moment each component holds a small amount of oil. Who is correct? A. A only C. both A and B B. B only D. neither A nor B

A. A only

Technician A says refrigerant hoses can be repaired. Technician B says damaged refrigerant hoses must be replaced. Who is correct? A. A only C. both A and B B. B only D. neither A nor B

A. A only

The blower motor on a vehicle does not run when the fan switch is in the low and medium position. It works properly when it is in the high position. Technician A says the problem is in the resistor block. Technician B says the problem is in the blower motor. Who is correct? A. A only B. B only C. Both A and B D. neither A nor B

A. receiver/dryer

The compressor on a vehicle has seized. Besides the new compressor, what other component should also be replaced? A. the receiver/dryer C. the condenser B. the evaporator D. all answers are correct

350 to 400

The high pressure cutout switch disengages the compressor clutch when high-side pressure reaches_________.

Suction

The largest and coolest line/hose in the A/C system is the__________line.

D. 26 to 29

When evacuating an A/C system, the vacuum pump should remain on and connected to the system for at least thirty minutes after _____ inches of mercury (in. Hg) is reached. a. 12 to 15 c. 22 to 25 b. 18 to 21 d. 26 to 29

A. liquid

When installing an A/C system filter: if the filter does not have an orifice, it should be installed in the _____ line. A. liquid C. discharge B. suction D. equalizer

C. receiver/dryer

A heating system includes all of the following parts except: A. heater core B. ventilation system C. receiver/dryer D. distribution plenum

D. all answers are correct

A loud squealing noise could be caused by ______. a. a worn compressor clutch b. oil on the compressor clutch c. a seized compressor d. all answers are correct

C. Both A and B

A poor heat condition is being discussed. Technician A says the coolant level in the engine's cooling system may be low. Technician B says the engine's thermostat may be faulty. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

thermal expansion valve

A sight glass is normally found on systems using R-12 and an_______________.

B. B only

A technician is trying, without success, to connect a 30-pound container of R-12 to his R-134a manifold gauge set. Technician A says the R-12 fitting is female and the gauge set fitting is also female. Technician B says the R-134a manifold gauge set uses a half-inch Acme thread, whereas the R-12 tank fitting has a standard thread. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

A vehicle with insufficient heater performance is being discussed. Tech A says the problem could be a stuck-open engine thermostat. Tech B says air could be trapped inside the heater core. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

Electric motors, Vacuum motors, Cables

Airflow control valves in the ventilation duct work are operated by

-459 degrees Fahrenheit (-273 degrees Celsius)

All materials or substances, as cold as ________________, have heat in them.

C. Both A and B

An R-12 to R-134a conversion procedure is being discussed. Technician A says leak-test the system and conduct a performance test prior to removing the R-12. Technician B says leak-test the system and conduct a performance test after charging the system with R-134a. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

B. the system is low on refrigerant

Bubbles in the sight glass indicate _____. a. air in the system b. the system is low on refrigerant c. evaporator flooding d. none of these answers is correct

B. B only

Tech A says a CCOT system has an expansion valve and a sight glass. Tech B says a CCOT system has an accumulator. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Tech A says hybrid vehicles have an electric water pump to circulate coolant through the heater core when the engine is stopped. Tech B says hybrid vehicles have a hot coolant storage tank to provide heat for passenger compartment when the engine is shut down. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

A. A only

Tech A says hybrid vehicles use electrically driven A/C compressors. Tech B says the compressors for hybrids use the same refrigerant oil as regular vehicles. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

A. A only

Tech A says in most cases, problems with the heating system are problems with the engine's cooling system. Tech B says a restricted heater return hose can cause excess heat in the passenger compartment. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

D. Neither A nor B

Tech A says refrigerant leaves the compressor as a high-pressure liquid. Tech B says the condenser changes the high-pressure liquid refrigerant into a high-pressure vapor. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

A. A only

Tech A says that evacuating an A/C system will remove air and moisture from the system. Tech B says that evacuating an A/C system will remove dirt particles from the system. Who is right? A. A only B. B only C. Both A and B D. Neither A nor B

B. B only

Tech A says the receiver/dryer is located on the low pressure side of the A/C system. Tech B says the accumulator is located on the low side of the system. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Technician A says air in the system can cause excessive pressure within the A/C system. Technician B says moisture can cause freeze-up at the expansion valve. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says pinhole leaks in the evaporator may be caused by acid formed when water and refrigerant are mixed. Technician B says leaks are most often found at hose connections and at the various fittings and joints in the system. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says suction lines connect the accumulator to the compressor. Technician B says discharge lines connect the compressor to the condenser. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Technician A says the suction line connected to the compressor should be cool to the touch. Technician B says the discharge line from the compressor to the condenser should be hot along its entire length. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says the thermostatic expansion valve and the fixed orifice tube perform the same function. Technician B says heat from the evaporator core surface is lost to the boiling and vaporizing refrigerant. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

B. B only

Technician A stores recycled refrigerant in emptied new refrigerant tanks. Technician B stores recycled refrigerant in UL-approved containers. Who is correct? A. A only C. both A and B B. B only D. neither A nor B

C. orange

The A/C compressors on hybrid vehicles have _____colored wires and wire harness covers to indicate they carry high voltage. a. red c. orange b. yellow d. violet

C. Both A and B

The blower motor does not run in any fan switch position. A check with a DMM reveals that power is getting to the motor. Tech A says the motor ground is bad. Tech B says the motor is burned out. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

False, because the components are pressure relief valve, desiccant bag, and the sight glass.

The expansion valve is a part of a receiver/dryer.

A. low-side

The manifold gauge set has an inches-of-mercury [vacuum] scale on the _____ gauge. a. low-side c. auxiliary gauge b. high-side d. all answers are correct

Ambient temperature switch, Thermostatic switch, Pressure cycling switch

Which of the following may be electrically connected in series with the compressor electromagnetic clutch?

PAG oil

Which of the following oils can be used in an R-134a system?

C. An incorrect air gap

A compressor clutch will not engage, but there is 14.2V and a good ground at the clutch coil connector. Which of these could be the cause? A. A low refrigerant level B. A locked-up compressor C. An incorrect air gap D. A bad pressure cycling switch

A. A only

A vehicle is being diagnosed for poor A/C performance. The engine is started, and when the system is set to MAX A/C, the compressor engages normally. When the temperature control knob is moved from hot to cool, only hot air blows out of the A/C outlets. Technician A says there is a problem with the air duct system or the controls. Technician B says the system is low on refrigerant. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

A. A only

A/C parts replacement is being discussed. Technician A says if the system has been open for more than two minutes, the entire system must be completely evacuated and a new accumulator must be installed. Technician B says if the seals on a new component have been removed for any length of time, the part must be completely flushed using only the recommended solvent. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both "The system is overcharged" and "Insufficient airflow through the condenser"

During a performance test, both the low-side and high-side pressures are above normal. Which of the following could cause this problem? a. The system is overcharged b. Insufficient airflow through the condenser c. Both "The system is overcharged" and "Insufficient airflow through the condenser" d. Neither "The system is overcharged" nor "Insufficient airflow through the condenser"

A. System is undercharged

During a performance test, both the low-side and high-side pressures are below normal. Which of the following could cause this problem. a. System is undercharged b. Defective [open] high-pressure cutout switch c. Restriction in liquid line d. Insufficient airflow through the condenser

C. both "service R-12 A/C systems" and "purchase R-12"

EPA certification is required to _____. A. service R-12 A/C systems B. purchase R-12 C. both "service R-12 A/C systems" and "purchase R-12" D. neither "service R-12 A/C systems" nor "purchase R-12"

A. A only

Electronic leak detectors are being discussed. Technician A checks for leaks with the engine off, the shop doors closed, and the overhead fans turned off. Technician B checks for leaks outdoors with the engine running. Who is correct? A. A only C. both A and B B. B only D. neither A nor B

C. low = blue, center = yellow, high = red

How are manifold gauge service hoses colored? a. low = green, center = orange, high = red b. low = green, center = yellow, high = red c. low = blue, center = yellow, high = red d. low = blue, center = green, high = red

C. slipping A/C belt

Large amounts of black dust around the clutch plate is an indication of _____. a. leaking compressor seal b. defective compressor clutch bearing c. slipping A/C belt d. restriction in high side

B. B only

R-12 to R-134a conversions are being discussed. Technician A says the original receiver/dryer or accumulator should not be replaced. Technician B says permanently install conversion fittings using a thread-locking chemical. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

A. A only

Tech A says European and Japanese manufacturers will eliminate R-134a A/C systems by 2011. Tech B says the United Sates will switch to R-22 in 2015. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Tech A says R-12 air-conditioning technicians must be certified. Tech B says R-12 air-conditioning equipment must be certified. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

A. A only

Tech A says R-12 is a chlorofluorocarbon (CFC) that damages Earth's ozone layer. Tech B says R-134a is a hydroflurocarbon (HFC) that causes even greater damage. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

B. B only

Tech A says a hybrid vehicle has a large reservoir of liquid refrigerant to keep the passenger compartment cool during long periods when the engine is shut down. Tech B says hybrid vehicles have electrically driven A/C compressors. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Tech A says an A/C system using CO2 (carbon dioxide) for a refrigerant will not contribute to global warming and is environmentally friendly. Tech B says CO2 refrigerant does not need to be recovered and recycled. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

B. B only

Tech A says the compressor can pump both liquid and vapor. Tech B says the compressor is driven off the crankshaft by a belt. who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Tech A says the magnetic clutch is usually pressure controlled, cycling the compressor on and off to regulate system temperature or pressure. Tech B says the clutch operates continually when the system is turned on. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

B. B only

Tech A says when the pressure applied to a liquid is increased, the boiling point decreases. Tech B says when the pressure on a liquid is suddenly released, heat energy is absorbed into the liquid. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

C. Both A and B

Technician A always wears safety glasses when working on air-conditioning systems. Technician B makes sure there are no open flames in the area prior to working on the A/C system. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says evacuating (pumping down) an air-conditioning system removes air and moisture from the system. Technician B says evacuating (pumping down) an air-conditioning system must be done anytime the system has been opened for repairs. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says if the suction line to the compressor is covered with thick frost, this might indicate that the expansion valve is flooding the evaporator. Technician B says the formation of frost on the outside of a line or component means there is a restriction to the flow of refrigerant. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says the cabin air filter should be replaced every 12,000 to 15,000 miles (19,300 to 24,140 km) or once a year. Technician B says some cabin air filters have a charcoal layer for odor absorption. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

D. Neither A nor B

Technician A says the normal operating pressures of R-134a are slightly lower than the pressures of R-12. Technician B says R-134a boils at 134 degrees Fahrenheit. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

B. B only

Technician A says the oil level of the compressor should be checked every year. Technician B says the system should be charged only after it has been completely evacuated. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

B. B only

Technician A says the presence of oil around a fitting of an air-conditioning line may indicate an oil leak but not a refrigerant leak. Technician B says using an electronic leak detector is the best way to find the source of a refrigerant leak. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

A. A only

Technician A says the refrigerant oil container should not be opened until it is time to use it and should be capped immediately after use. Technician B says after the system has been opened, compressed air should be used to flush dirt, moisture, and old refrigerant oil out of the system. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

B. B only

Technician A says the sight glass is located in the suction line, between the accumulator and compressor. Technician B says the sight glass is located on the receiver/dryer. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

C. Both A and B

Technician A says there should be a gradual change from hot to warm as you move your hand along the return bends of the condenser from the bottom to the top. Technician B says a restriction in the condenser will be evident by a sudden change in temperature. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

A. A only

Technician A uses a DMM [digital multimeter] to test the resistor block for opens. Technician B tests the resistor block with a lab scope. Who is correct? a. A only c. neither A nor B b. B only d. both A and B

C. both "ASE" and "MACS'

The EPA-approved certification exam on refrigerant recovery and recycling is administered by _____. a. ASE c. both "ASE" and "MACS' b. MACS d. neither "ASE" nor "MACS'

D. blower motor resistor

The blower motor in the schematic shown works only with the blower switch in the number 4 position. This could be cause by a failed: A. blower motor B. blower motor ground C. blower motor relay D. blower motor resistor

Under the dash

The evaporator is located___________________.

b. 60

The filling level of a refrigerant container should never exceed _____ percent of the container's gross weight rating. a. 50 c. 75 b. 60 d. 90

D. a broken compressor reed valve

The high side pressure in an A/C system is above specs. Any of these could be the cause EXCEPT: A. an overcharge of refrigerant B. a restricted air flow across the condenser C. a plugged expansion valve D. a broken compressor reed valve

B. ultraviolet [UV]

The leak-test dye in an A/C system will appear luminous yellow-green when illuminated by a(n) _____ light. a. infrared [IR] c. blue laser b. ultraviolet [UV] d. 5,200°K mercury vapor

D. all answers are correct

When is a manifold gauge set used? A. discharging B. charging C. evacuating D. all answers are correct

d. completely

When replacing a typical A/C system component, the system must be discharged _____. a. approximately 2 percent b. approximately 50 percent c. approximately 75 percent d. completely

c. a water flow control valve not opening fully

Which of the following cannot cause excessive heat? a. a loose or damaged control cable b. a heater control valve stuck open c. a water flow control valve not opening fully d. a faulty thermostatic fan

B. B only

A poor heat condition is being discussed. Tech A says a disconnected engine vacuum hose could not cause the problem. Tech B says a seized blend door could cause the problem. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

D. a restriction in the receiver/dryer

Frost on the outside of the receiver/dryer, but not on the liquid line between the condenser and receiver/dryer indicates ______. a. the system is overcharged b. a clogged accumulator c. a restriction in the suction line d. a restriction in the receiver/dryer

cable, thermostat, and vacuum motor

Heater control valves are operated by a ___________________.

hybrid vehicles

Heater cores with electric PTC heater strips are used in what type of vehicle?

The control cables have slipped loose from the dash control or door arm.

If little or no resistance is felt while operating the temperature control lever, the problem is most likely _____________________.

Heat flow, Heat absorption, Pressure and Boiling Points

On which of the following laws of nature is the air-conditioning system based?

B. recover it and treat it as contaminated.

Prior to recovery, an unknown refrigerant is identified. The technician should: A. discharge it into the atmosphere. B. recover it and treat it as contaminated. C. recover it and recycle it as R-12. D. recover it and recycle it as R-134a.

a. should never be mixed

R-12 and R-134a _____. a. should never be mixed b. may be mixed after a system has been converted from R-12 to R-134a c. use the same manifold gauge sets d. all answers are correct

C. Both A and B

Tech A repairs a leaking heater core. Tech B replaces it with a new core. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

The pressure applied to it increases

The boiling point of a liquid increases as_______________.

B. B only

The owner of a car complains of a whistle or hiss only after the engine is shut down and only when the air-conditioning has been running. Technician A says there is a broken or leaking vacuum hose inside the dash. Technician B says this is a normal noise caused by the fluid pressure equalizing after the engine is turned off. Who is correct? a. A only c. both A and B b. B only d. neither A nor B

Absorb moisture inside the system

The purpose of the desiccant bag in the receiver/dryer or accumulator is to_____________.

Evaporator orifice (inlet)

The refrigerant is at its lowest pressure and temperature at the___________________.

C. Both A and B

The technician measures 14.2 volts at the A/C clutch coil, but the A/C clutch will not engage. Technician A says that a bad clutch coil could be the cause. Technician B says that a bad clutch coil ground could be the cause. Who is right? A. A only B. B only C. Both A and B D. Neither A nor B

A. A only

Thermal expansion valves are being discussed. Tech A says the TEV regulates the refrigerant flow to the evaporator by balancing the inlet flow to the outlet temperature. Tech B says the TEV is closed when the temperature at the outlet of the evaporator is high. Who is correct? A. A only B. B only C. Both A and B D. Neither A nor B

B. the low side only

To charge an A/C system while it is running, the refrigerant should be added to: A. the high side only B. the low side only C. both the high and the low sides D. neither the high or the low side

True

True or False? Water vaporizes into steam at 212 degrees Fahrenheit.

C. cleaning the evaporator core with a disinfectant solution

Unpleasant odors coming from the A/C system can be eliminated by ______. a. back-flushing the A/C system with alcohol b. evacuating and recharging the system c. cleaning the evaporator core with a disinfectant solution d. draining and replacing the refrigerant oil

B. High-pressure vapor leaves the evaporator at the top.

Which of the following statements concerning evaporators is NOT true? A. Low- pressure liquid enters the evaporator at the bottom. B. High-pressure vapor leaves the evaporator at the top. C. The evaporator is located underneath the dash. D. Air passing over the evaporator loses its heat to the cooler surface of the core.

A. The evaporator changes heated refrigerant to a liquid.

Which of the following statements is NOT correct? A. The evaporator changes heated refrigerant to a liquid. B. Automatic temperature controls maintain a set passenger compartment temperature. C. Air- conditioning/heater systems can be computer controlled. D.Heaters and air-conditioners use the same plenum chambers.

B. The liquid line from the condenser outlet to the evaporator inlet should be cool.

Which of the following statements is NOT true about orifice tube systems? A. The suction line must be cool to touch from the evaporator outlet to the compressor. B. The liquid line from the condenser outlet to the evaporator inlet should be cool. C. The evaporator should feel very cold. D. The accumulator must be cool to the touch.

B. low refrigerant level

With the A/C system operating at an ambient (outside) temperature of 85 degrees Fahrenheit, the low pressure gauge reads 5 psi and the high pressure reads 105 psi. What do these readings indicate? A. normal operation B. low refrigerant level C. a restriction in the high side D. broken compressor reed valves

Axial

variable displacement compressors are normally______ compressors with a pivoting wobble plate.

A. Permanently install conversion fittings using new hose clamps around fittings

Which of the following is not recommended while converting an R-12 system to R-134a? A. Permanently install conversion fittings using new hose clamps around fittings B. Install conversion labels and remove the R-12 label C. Recharge the system with R-134a to approximately 80 percent of the original R-12 charge D. Remove all oil in the system and replace with the original type and the same amount

C. Evacuation is a process that removes all traces of air, moisture, and refrigerant from the system

Which of the following statements best defines the term "evacuation"? A.Evacuation is a process in which the refrigerant in a system is released B. Evacuation is a condition that exists when a compressor runs until there is no refrigerant left in the system C. Evacuation is a process that removes all traces of air, moisture, and refrigerant from the system D. Evacuation is a process that uses air to force moisture and dirt out of the system

C. R-12 is destructive to Earth's ozone layer

Which of the following statements concerning R-12 is correct? A. R-12 is a hydroflurocarbon. B.R-12 boils at 0 degrees Fahrenheit (-18 Celsius) C. R-12 is destructive to Earth's ozone layer D. All answers are correct

D. None of these answers are correct

Which of the following statements is not correct? A. Refrigerant leaves the compressor as a high-pressure, high-temperature liquid. B. Refrigerant leaves the condenser as a low-pressure, high-temperature liquid. C. Refrigerant returns to the compressor as a low-pressure, high-temperature vapor. D. None of these answers are correct.

C. The accumulator is located between the condenser and the receiver/dryer.

Which of the following statements is not correct? A. The condenser is normally mounted in front of the radiator. B. The receiver/dryer is a storage tank for liquid refrigerant from the condenser. C. The accumulator is located between the condenser and the receiver/dryer. D. All answers are correct