Unit 15

Question 1

Questions 1-12 based on pictorial schematic

Answer 1

Use diagram to answer questions

Question 2

Heat contacts _______ on the rise in temperature and close on the _______ drop in temperature

Answer 2

Open on the rise and close on the drop

Question 3

What can be done if an older clamp on a meter cannot measure low current in a circuit?

Answer 3

Wine 10 coils of wire and measure. The result should then be divided by 10 for current reading. 

Question 4

Defrost can be terminated by ______ or ________.

Answer 4

Time or temperature

Question 5

Two distinct types of wiring schematics/diagrams are furnished with equipment. What are the diagrams called? 

Answer 5

Ladder Diagram and Pictorial Diagram

Question 6

Unit containing compressor, evaporator, condenser and me during device all in one unit such as a window air conditioner.

Answer 6

Package air conditioner

Question 7

Uses power and have either a magnetic coil, or a resistant circuit referred to as loads.

Answer 7

Power consuming devices

Question 8

Wired in series in the heat relay coil circuit (heat anticipator) resistor that can vary its resistance.

Answer 8

Variable resistor

Question 9

Closes a set of contacts in the high-voltage circuit that starts the indoor fan

Answer 9

Fan relay coil

Question 10

Side nearest the power source

Answer 10

Line side of the switch

Question 11

Voltage measured across the start winding in a single face motor while it is turning at full speed. Difference in voltage between any two parts of a circuit. 

Answer 11

Potential voltage

Question 12

Side of the switch the load is connected

Answer 12

Load side of the switch

Question 13

Passes power on power consuming devices

Answer 13

Non-power consuming devices

Question 14

A magnetic coil is energized initiate a heat cycle

Answer 14

Electrical heat relay

Question 15

Short piece of wire with alligator clips or connector on each end used to bypass components in an electrical circuit. Wire gauge should be large enough to handle current in circuit. 

Answer 15

Insulated jumper

Question 16

Wired in parallel to cooling contacts, non-adjustable resistor

Answer 16

Fixed resistor

Question 17

T/F
The defrost termination solenoid is often referred to as a “Z” coil

Answer 17

True

Question 18

T/F
The ladder diagram is easier to use for locating the different components in the circuit 

Answer 18

False

Question 19

T/F
Jump terminals R and C in the thermostat subbase to energize the heating coil 

Answer 19

False

Question 20

T/F
Divide a transformers capital VA rating by the primary voltage to determine the maximum the current transformer can handle before the low-voltage fuse is blown 

Answer 20

False
Divide VA by lower voltage in transformer

Question 21

T/F
If there is voltage at the light socket, and the lightbulb fails to illuminate, the bulb is bad 

Answer 21

True

Question 22

T/F
If Line 1 of a circuit had a potential of 120 V and Line 2 was neutral, the potential voltage (difference) between Line 1 and Lone 2 would be 0 V 

Answer 22

False

Question 23

T/F
The cooling anticipator is bypassed from the circuit when the thermostat is satisfied/opened 

Answer 23

False

Question 24

T/F
While troubleshooting a 24 V circuit consisting of a thermostat, a pressure control, and a contactor coil, the technician reads 24 V across the thermostat, 0 V across the pressure control, and zero votes across the contact coil. The technician makes the following statements.
A)The transformer is burned out
B)The thermostat is open
C)The contractor coil is energized
D)The pressure control contacts are closed

Answer 24

False

Question 25

Electrical controls are divided into two categories: power passing and _________

Answer 25

Power consuming

Question 26

While checking a simple series, 115 V circuit, containing a fuse, a switch and a lightbulb, the technicians voltmeter reads 115 V across the lightbulb socket. The lightbulb is not on. He correctly includes the ________is defective.

Answer 26

Bulb

Question 27

Draw the ladder diagram for an evaporator fan motor with a switch that turns the fan on/off. Power supply is 115 V.

Question 28

Questions 39-43 use diagram to draw path of current and answer questions

Question 29

If a circuit has a current draw of 0 amps, is the load energize?

Answer 29

No