Deck 30: Electric Heat

Question 1

If the fan were to fail and the limit switch stuck closed, the element would be cut off by the ____________________.

Answer 1

fusible link

Question 2

The benefits of electric baseboard heating are that ____ .

A) each room can be controlled individually
B) they are inexpensive to install
C) they operate on a 24-V power supply
D) Both a and b.

Answer 2

D

Question 3

The resistance wire used in electric heating elements is usually ____.

A) copper
B) nickel steel
C) nickel chromium
D) aluminum

Answer 3

C

Question 4

Electric baseboard heaters are classified as ____ .

A) natural-convection heaters
B) forced-convection heaters
C) forced-draft conductors
D) radiant heaters

Question 5

Any unit heater designed to have air forced across the element should not be operated without the ____ operating .

A) fuse
B) interlock
C) element
D) fan

Question 6

Generally speaking, electric heat is very efficient but can be more expensive to operate compared to oil and gas .

Question 7

One potential safety hazard that all technicians should be aware of when working on an electric furnace is that there are many exposed electrical connections behind the inspection panels .

Question 8

Electric heating units provide almost instant heat. Therefore, anticipators are not needed in electric heat thermostats.

Question 9

All electric furnaces use package sequencers.

Question 10

In order to prevent a duct-mounted electric heater from being energized when the fan is not on, a(n) ____________________ should be used.

Question 11

The limit switch is used on the electric element assembly to ____.

A) start the unit if the thermostat malfunctions
B) ensure that the fan stops when the unit cools down
C) start the unit prematurely on a cold day
D) shuts off the unit if high temperature occurs

Question 12

A set of contacts actuated by a bimetal strip with a low-voltage wire wrapped around it is called a(n) ____________________.

Question 13

If the number two contact on a package sequencer fails to close, the number three contact can still close.

Question 14

In order to provide time delay between stages of electric heat, the controls that are used are called ____________________.

Question 15

Radiant heat is transferred by ____.

A) ultraviolet rays
B) infrared rays
C) ionization
D) refraction

Question 16

Some units may be designed to move enough air across the heating elements so that they do not glow.

Question 17

An electric heating unit that utilizes ductwork to distribute the heated air is classified as a ____ .

A) natural-convection heater
B) forced-convection heater
C) forced-draft conductor
D) radiant heater

Question 18

Quartz and glass panel electric units are classified as ____.

A) natural-convection heaters
B) forced-convection heaters
C) forced-draft conductors
D) radiant heaters

Question 19

Which of the following elements is not a power-consuming device ?

A) The sequencer heater coil.
B) A magnetic solenoid that moves the armature in a contactor.
C) The contacts of a contactor.
D) The blower motor.

Question 20

A 10 Kw heating element, operating on rated 240 V, will generate ____ Btu/h .

A) 29,319
B) 31,062
C) 34,130
D) 35,875

Question 21

How is the formula Q_S = 1.08 × cfm × TD often called ?

Question 22

For each watt of electrical power, ____________________ Btu/h are generated .

Question 23

Where in a room are electric baseboard heaters normally placed ?

Question 24

Where are unit and wall electric heaters typically mounted ?

Question 25

Why do most electric furnaces have several heating elements that are activated in stages ?

Question 26

Explain the difference between a "pictorial" diagram and a "schematic."

Question 27

How should you determine the heat anticipator setting on a room thermostat ?

Question 28

Radiant electric heating panels used for ceiling installation are often made of  ____________________  with wire heating circuits running throughout.

Question 29

Why aren't contactors used in residential and small commercial electric heating units?