Exam 54: Heating and Air Conditioning

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

The change from a liquid to a vapor is called ____________________.

Technician A says European and Japanese manufacturers shipping vehicles to the US will eliminate R-134a A/C systems by 2017. Technician B says the United States will switch to R-22 in 2015. Who is correct?

The customer has reported that little heat comes out of the floor duct. 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 malfunctioning engine thermostat can be the cause of poor heater performance.

The blower motor does not run in any fan switch position. A check with a DMM reveals that power is getting to the motor. Technician A says the motor ground is bad. Technician B says the motor is burned out. Who is correct?

Which statement is true?

What tool would you use to check the operation of a vacuum motor?

Technician A says the receiver/drier is located on the low [pressure] side of the A/C system. Technician B says the accumulator is located on the low side of the system. Who is correct?

An A/C system cools the air by moving heat from the confined space of the passenger compartment to the engine cooling system.

If little or no resistance is felt while operating the temperature control lever, the problem is most likely which of the following?

Technician A says R-12 air-conditioning technicians must be certified. Technician B says R-12 air-conditioning equipment must be certified. Who is correct?

When the air-conditioning is set to the maximum position, passenger compartment air is ____________________.

Describe the function of a cycling clutch in an air-conditioning system.

PAG oil works well with R-12 refrigerant.

Heater control valves are operated by a ______.

Aluminum tubing is often used to connect air-conditioning components where flexibility is not required.

What type of vehicle uses heater cores with electric PTC heater strips?

The ____________________ displacement compressor automatically changes volume and the amount of refrigerant flow.

In an automotive A/C system the substance used to move heat from the passenger compartment to the outside air is called the ____________________.