Category One
Electric heating equipment is typically
less expensive to purchase and more expensive to operate than fossil fuel heating equipment.
Electric baseboard heaters are typically controlled by
heater-mounted line-voltage thermostats
Three common controls used in central electric heat applications are
thermostats, contactors and sequencers
The heat anticipator is a(n)
adjustable device that is wired in series with the thermostat’s heating contacts.
Dirty air filters on an electric forced-air furnace can cause
reduced airflow and increased internal appliance temperature
Portable or small space heaters with glowing coils transfer heat by
radiation
From an installation standpoint, electric boilers have the benefit of not requiring
flue or vent piping
The fusible link is best described as a(n)
one-time, safety device
The sequencer is responsible for
staggering the starting and stopping of multiple stages of electric heat.
On furnaces that are equipped with belt-driven blower assemblies, which of the following can result if the belt is too loose?
Reduced airflow and increased internal appliance temperature
If the distance between a heat source and the heat target is doubled, the amount of sensed heat at the target location will be
one-quarter of the amount of heat sensed at the initial location.
What is the approximate efficiency of an electric furnace with respect to its ability to convert electrical energy to heat energy?
100%
Which of the following statements is true regarding the limit switch and the fusible link?
The fusible link melts at a temperature that is higher than the temperature at which the limit switch opens.
The wiring diagram that shows the location of each system component is the
pictorial diagram.
If the proper voltage is supplied to an electric heating element and it does not get hot,
the heating element is defective.
Electric radiant heating elements
are often controlled by individual thermostats.
The electric resistance strip heaters in an electric furnace are insulated from the rest of the appliance using which materials?
Mica or ceramic
The low-voltage thermostat is often used to control an electric heating system because it is compact, quick to respond to load changes, and it
is safe
Referring to Figure 30.22, the indoor fan motor will operate at low speed
whenever the high-voltage disconnect switch is closed and sequencer contacts 3-4 are closed.
If the thermostat is calling for heat, but the appliance is providing insufficient heat, which of the following is the most likely cause for system malfunction?
The supply voltage to the appliance is too low.
Baseboard heaters transfer heat by
convection
What is the purpose of an interlock circuit on an electric forced-air furnace?
It prevents the heaters from coming on if the blower is not energized.
An isolating thermostat subbase is easily identified because it has which of the following terminals?
RH and RC
Referring to Figure 30.23, each electric strip heater is protected by how many safety devices?
4
The material often used to manufacture electric strip heater element wire is
nickel chromium (nichrome).