Deck 18: Troubleshooting Modern Refrigeration Heating and Air 252dconditioning Control Circuitry and Systems

Question 1

The electrical wiring diagram is the technician's primary tool in electrical troubleshooting.

Answer 1

True

Question 2

After determining that voltage is available to the control circuit of a residential air-conditioning system, what four devices should be checked when troubleshooting the system?

Answer 2

Once it is determined that voltage is available to the control circuit, the only items left to check are the devices in the circuit. In the control circuit, there are four devices that should be checked: the low-pressure and high-pressure switches, the thermostat, and the contactor coil.

Question 3

How are thermostats and pressure switches controlled?

Answer 3

Thermostats and pressure switches are controlled by the temperature of the medium surrounding them or by the pressure at the point where they are connected to the system.

Question 4

Troubleshooting the electrical control circuits in a cooling, heating, or refrigeration system is basically common sense.

Question 5

The low-voltage thermostat used on residential and light commercial conditioned air systems is difficult to diagnose because of its complexity and the fact that it is used for several purposes in a heating and cooling system.

Question 6

What is the first check that a technician should make on a service call?

Question 7

Troubleshooting charts usually need to be ordered because they are not included with equipment at the time of shipment.

Question 8

Explain the purpose of the electronic self-diagnostic feature. How does it communicate results?

Question 9

Electric switching devices such as contactors and relays rarely cause electrical problems.

Question 10

A(n) ____________________ chart is a graphical representation of a troubleshooting procedure for a particular unit.

Question 11

Most diagrams have a(n) ____________________ that helps the technician to interpret the abbreviations used in the diagram.

Question 12

Volt-ohm meters only measure volts and ohms.

Question 13

Because electric motors are inexpensive, there is no real need to troubleshoot them.

Question 14

Manual switches are basic devices that are used to set the temperature of a motor.

Question 15

A(n) ____________________ is an overload device that senses the current draw of the compressor through the lockout loop (LL).

Question 16

The ____________________ diagram is a picture of the control panel and is sometimes called a component arrangement diagram.

Question 17

What two types of meters are commonly used in the industry?

Question 18

The electric motor is the smallest load used in most heating, cooling, and refrigeration systems.

Question 19

The ____________________ type of diagram asks questions that require a response before the technician proceeds to the next step.

Question 20

The most important tools that the technician has for troubleshooting are electric meters.