ACR 205 midterm

Electric heat can be expensive to operate compared to other heat sources because __________.

• it requires more components to produce the heat

• it takes large amounts of electrical energy to produce heat

• conversion of electricity to heat is too slow to keep up with a structure’s heat loss

Three common controls used in electric heat applications are __________.

• thermostats, sequencers, and contactors

• sequencers, fan delays, and timers
  

•  thermostats, pressure controls, and solenoids
  

Safety devices commonly found on electric furnaces are the limit switch and a fusible link.

• True

• False

The low-voltage thermostat in an electric furnace is used to control __________.

• sequencers and contactors

• heating elements and contactors

• gas valves and relays

In many low-voltage thermostat models, when there are R_h and R_c terminals ___________.

• only the R_h terminal should be used for power

• only the R_c terminal should be used for power

• a jumper wire should be place between them to control both the heat and cooling functions

The fusible link is set to melt at ________________.

• a temperature that is higher than the operating temperature of the high limit

• 200°F

• the same temperature as the maximum operating temperature of the high limit

Power-passing devices are wired in parallel with the power-consuming devices.

• True

• False

Most electric furnaces have several heating elements that are activated in stages to ____________.

• allow the furnace to slowly heat up

• allow the blower motor to establish airflow

• avoid energizing a high-power load all at once

The material often used to manufacture electric strip heater coils is         .

• Nichrome

• Penny

• Nickel

A disadvantage of a central forced-air electric furnace is that

• There is zone control

• there is no zone control for individual rooms.