May be a bad Thermistor

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from the Tech Sheet - 3977696

Thermistor Test or Dryer Beeps 3 Times When PTS Pressed

An electronic temperature sensor called a thermistor is used in this model in place of an operating thermostat.

The Even Heat control monitors the exhaust temperature using the thermistor and cycles the heater relay on and off to maintain the desired temperature.

Procedure

Begin with an empty dryer and a clean lint screen.

1. Set the following configuration:

Timer Dial - TIMED DRY

Fabric Care/Temperature switch - COTTON HIGH

Signal switch - LOUD

Door - must be closed

2. Press the Push To Start switch.

a. If you hear three short beeps and the dryer shuts off after several seconds,

the thermistor or wire harness is either shorted or open.

Check wire connections at Even Heat control and thermistor.

If wiring is functional, replace the thermistor:

b. If the dryer appears to operate correctly, proceed to step 3.

3. Remove exhaust vent and start the dryer.

a. Turn Fabric Care/Temperature switch to desired temperature to be tested,

and select 20 minutes on the TimedDry dial.

Hold a glass bulb thermometer capable of reading from 90°F to 180°F in the center of the exhaust outlet.

Measure exhaust temperatures with heater off and on.

The correct exhaust temperatures are as follows:

FABRIC CARE/TEMP.

SWITCH SETTING . . . . HEAT TURNS OFF. . . . . . . . HEAT TURNS ON

COTTON . . .. . . . . . . . 150°F . . . . . . . . . 10° - 15°F below heat off

NORMAL/PERM PRESS 140°F . . . . . . . . . . 10° - 15°F below heat off

KNIT/CASUAL . . . . . . . 125°F . . . . . . . . . . 10° - 15°F below heat off

ULTRA DELICATE . . . . . 115°F . . . . . . . . . .10° - 15°F below heat off

b. If the exhaust temperature is not within specified limits, check the resistance of the thermistor.

THERMISTOR RESISTANCE

TEMP ° F . . . . . RES. K . . . . . TEMP. ° F . . . . . RES. K

50° 19.9 100° 5.7

60° 15.3 110° 4.7

70° 11.9 120° 3.7

80° 9.2 130° 3.1

90° 7.4 140° 2.5

c. If the thermistor resistance checks within normal limits, replace the Even Heat control.

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Source: Kenmore Elite electric dryer stops mid cycle