How Dryer Thermistors Work

How Does A Dryer Thermistors Work Dryer Thermistors are wired directly to the dryer control board The board constantly monitors the resistance of the thermistor

Dryer thermistors that control the heater are always in the airflow. Thermistors are heat sensors that change resistance with temperature.

Dryer thermistors are wired directly to the dryer control board. The board constantly monitors the resistance of the thermistor for subtle changes as the heater heats the airflow.

When the control board senses a specific resistance value it opens up the low voltage circuit to the heater relay coil. When power is cut off to the relay coil the heat contacts open interrupting the current flow to the heater. The heater turns off and the cycle starts over.