Deck 23: Electric Heat

Question 1

On a call for heat on an electric furnace, __________ volts should be read between W and G on the thermostat terminal strip.

A) 0
B) 24
C) 115
D) 220

Answer 1

A

Question 2

When troubleshooting an electric furnace, you find that the fusible link on the first heating element is melted. What would be the most likely problem?

A) defective heating element
B) tripped circuit breaker
C) defective fan motor
D) defective fusible link

Answer 2

C

Question 3

Electric heating elements are rated in __________.

A) kilowatts
B) watts
C) amps
D) Btus

Answer 3

A

Question 4

Electric, resistive-type heating is by far the most efficient of all types of heating.

Question 5

If an electric furnace were equipped with three 5-kW heating elements, which device would allow them to cycle at different intervals?

A) interlock
B) limit switch
C) room thermostat
D) sequencer

Question 6

When troubleshooting an electric furnace, you find that the blower is operating, but cold air is coming out of the ducts, the thermostat is calling for heat, and the fan setting is on auto. What would be the most likely problem?

A) defective fan relay
B) defective thermostat
C) open heating elements
D) defective blower motor

Question 7

The single most important feature on electric furnaces is a/an __________ that exists between the blower motor and the electric heating elements.

A) sequencer
B) fuse
C) high limit
D) interlock

Question 8

Electric heat may, in many cases, be expensive, but it is 100% efficient.

Question 9

The indoor fan must energize as soon as the electric heating elements are energized.

Question 10

Which device will open first if a high temperature condition exists on an electric furnace?

A) fusible link
B) limit switch
C) high-pressure control
D) interlock

Question 11

On a call for heat on an electric furnace, __________ volts should be read between R and Y on the thermostat terminal strip.

A) 0
B) 24
C) 115
D) 220

Question 12

Electric duct heaters can only be used with heat pump systems.

Question 13

Improper belt tension on furnace blowers does not increase power consumption or reduce the equipment's life expectancy.

Question 14

The wire used in electric heating elements has a low resistance to current flow.

Question 15

On a call for heat on an electric furnace, __________ volts should be read between R and G on the thermostat terminal strip.

A) 0
B) 24
C) 115
D) 220

Question 16

If the thermostat is calling for heat, __________ volts should be read between R and W on the thermostat terminal strip.

A) 0
B) 24
C) 115
D) 220

Question 17

One kilowatt will produce __________ Btus of heat energy.

A) 4133
B) 3413
C) 1334
D) 3134

Question 18

Which type of wire is typically used to construct electric heating elements?

A) copper
B) aluminum
C) nichrome
D) any of the above

Question 19

Electric furnaces require a special room thermostat to control the temperature.

Question 20

Residential electric furnaces require which type of power supply?

A) 115-V
B) 220-V single-phase
C) 220-V three-phase
D) 440-V three-phase

Question 21

When troubleshooting an electric furnace, you find that the limit switch on the first heating element is cycling on and off. What would be the most likely problem?

A) defective limit switch
B) defective sequencer
C) defective heating element
D) dirty air filter

Question 22

Electric furnaces have an efficiency of __________%.

A) 70
B) 80
C) 90
D) 100

Question 23

Which of the following is typically used as an interlock in an electric furnace?

A) sequencer
B) limit switch
C) fusible link
D) sail switch

Question 24

List two methods for proving airflow on an electric furnace.

Question 25

What would be the electric heat requirement for a house with a 50,000 Btu heat loss? (Please show your work.)

Question 26

A 5-kW electric heating element will generate __________ Btus of heat.

A) 3413
B) 17065
C) 34130
D) 5000