Electric Clothes Dryer

• A thermostat controls the heat in an electric clothes dryer.
  
  

Identification

• A thermostat is the control switch which determines the level of heat intensityt. It is a
  temperature-sensitive device that senses the hot air temperature inside the clothes dryer.
  
  

Function

• When heat is requested, the line voltage electric heaters become energized.
  
  

Significance

• If the heaters remain energized throughout the drying cycle, they will overheat and a fire will result within the dryer. Therefore, a thermostat is used to control the heat.
  
  

Process

• According to Elvet Richardson, an HVAC instructor at Technical Career Institutes in New York City, when the drying temperature reaches the level set by the themostat, the themostat opens, de-energizing the heaters. The drying barrel continues to rotate with the clothes. As the temperature within the dryer drops, it soon reaches the cut-in temperature of the thermostat, which is the lower set point.
  
  

Result

• The thermostat closes and the heaters are energized, maintaining the temperature. This pattern continues throughout the drying cycle. At the end of the cycle, a timer shuts off the dryer.