Learn how your appliance is supposed to operate so you can determine if it is malfunctioning.
Top of the line Whirlpool and Kenmore (usually Series 80 or Series 90) dryer models may utilize an "Even Heat" control sometimes called AccuDry™. These models use a thermistor (temperature variable resister) to sense dryer temperature instead of a standard dryer thermostat, a moisture sensor plus an electronic board to control dryer heating, running of the motor and even advancing of the timer. This system adds a whole new complexity to diagnosing dryer malfunctions.
During "Automatic Mode", the electronic control determines the length of time the cycle should run to dry the load. The control will stall the timer motor or allow it to advance for 3 seconds on and 33 seconds off. This is based on the number of 'hits' the moisture sensor detects, the average exhaust temperature and the time already taken during the cycle. If the control senses no moisture, such as a small load or an empty drum, it will advance the timer at 100% to end the cycle as soon as possible.
In the "Cool-Down" portion of the cycle, the timer will advance to the beginning of the "Wrinkle Guard" position and pause until cool-down is completed. The control will end the cycle when the exhaust temperature has dropped to ~105°F or the cool-down has been operating for 10 minutes.
During the "Timed Dry" cycle, the timer motor will continue to be pulsed by the even heat control board until the selected time has elapsed.
There have been numerous variations of "Even Heat" control boards used in the different dryer models. The exact functioning of the control in any particular dryer may vary slightly from the above descriptions.
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