Question 1

A variable displacement compressor:

Accepted Answer

A variable displacement compressor changes the compressor displacement to regulate the temperature by using a control valve to change the angle of the wobble plate. It does not cycle the clutch to regulate temperature. Therefore, statement B and C are correct.

Question 2

In order for the air condition system to operate properly the refrigerant in the condenser must be:

Accepted Answer

The refrigerant in the condenser must be at a higher temperature than the ambient air to effectively transfer heat from the refrigerant to the outside environment. This temperature difference drives the heat exchange process, allowing the refrigerant to release heat and condense back into a liquid form.

Question 3

Where would you expect to find the condenser mounted on the truck?

Accepted Answer

The condenser is typically mounted in front of the engine radiator in order to receive air flow and cool the refrigerant.

Question 4

Of the following compressor styles which one uses the fewest moving parts?

Accepted Answer

The answer of Of the following compressor styles which one...

Question 5

In regards to the two lines that are attached to the compressor:

Accepted Answer

The smaller line is indeed the discharge line because it carries high-pressure refrigerant from the compressor to the condenser. The larger line is the suction line, which returns low-pressure refrigerant back to the compressor from the evaporator.

Question 6

What is contained in the receiver-drier that captures the moisture that has entered the air conditioning system?

Accepted Answer

The desiccant is a material inside the receiver-drier that absorbs moisture that has entered the air conditioning system. The pickup tube is a component that draws refrigerant into the compressor, the strainers are filters that remove debris from the refrigerant, and the sight glass is a window that allows the technician to see the refrigerant flow in the system. However, only the desiccant captures moisture.

Question 7

How is air forced through the fines of the condenser?

Accepted Answer

The air is forced through the fines of the condenser by the ram air effect as the vehicle moves forward as well as by an engine mounted fan that pulls air through the condenser.

Question 8

If the receiver drier becomes saturated which of the following could occur?

Accepted Answer

If the receiver drier becomes saturated, all of the listed options are possible outcomes. The excess moisture can react with the refrigerant to form hydrochloric acid, the moisture can collect together and freeze into a blockage, and an operator may complain of intermittent performance from the air conditioning system.

Question 9

In regards to the two piston compressor what causes the intake read valve to open?

Accepted Answer

The intake reed valve in a two-piston compressor opens due to differential pressure. When the pressure inside the cylinder is lower than the pressure in the intake line, the differential pressure causes the intake reed valve to open, allowing refrigerant or air to flow into the cylinder for compression.

Question 10

Identify the two refrigerant lines that are attached to the compressor.

Accepted Answer

The two refrigerant lines attached to the compressor are the suction (low pressure) line and the discharge (high pressure) line. These lines are also referred to as the suction and discharge lines. Option A is incorrect because the terms exhaust and intake are not used when referring to refrigerant lines. Option C is incorrect because the terms turbo and induction are not used in refrigeration systems. Option D is incorrect because the terms liquid and vapor are used to refer to the state of the refrigerant, not the lines attached to the compressor.

Question 11

If a drier becomes restricted it may be detected by _____________________ when the system is operating.

Accepted Answer

A restricted drier in a refrigeration or air conditioning system will cause a temperature drop across it due to the restriction of refrigerant flow, leading to a warm inlet and a cold outlet.

Question 12

What happens to the superheated refrigerant as it passes through the condenser?

Accepted Answer

As the superheated refrigerant passes through the condenser, it is cooled by the ambient air or cooling water, causing it to condense from a vapor to a liquid. This process increases the refrigerant's pressure, resulting in a high pressure liquid state.

Question 13

Which of the following functions does the receiver-drier not perform?

Accepted Answer

The receiver-drier does not cause refrigerant to change states; this is the job of the compressor and the evaporator. The receiver-drier filters refrigerant, removes moisture from the refrigerant, and stores the refrigerant.

Question 14

Which of the following is true when mounting a receiver-drier?

Accepted Answer

All the statements are correct when mounting a receiver-drier. The refrigerant lines must be connected to the right ports, the receiver-drier should be installed within 15 degrees of vertical position, and it should be installed immediately after removing the protective caps.

Question 15

Which of the following should not be done when servicing a condenser?

Accepted Answer

Using a high-pressure washer can damage the cooling fins of the condenser and cause leaks, so it is not recommended to use a pressure washer when servicing a condenser. Choices A, C, and D are all appropriate methods for servicing a condenser.

Quiz 4: Air Conditioning Components: Compressor, Condenser, and Receiver-Drier