There are two thermistors (thermal sensors) in this dryer; one is the outlet thermistor located on the blower housing and the other is the inlet thermistor located on the heating element housing as an integral part of the high-limit thermostat.
These thermistors are negative coefficient type and monitors the dryer temperature on their locations according to their resistance which varies inversely with the temperature. The resistance drops as the temperature rises and rises as temperature drops.
One or both of the thermistors has an open connection or high resistance which makes the electronic control board thinks that the dryer temperature is low no matter how high it is. The electronic control board then doesn't cycle the heater relay and continue to turn on the heating element. The dryer temperature continues to rise and this blows the thermal fuse.
Make sure the thermistors are connected snugly. Remember that loose or open connection means high (infinite) resistance which makes the electronic control thinks of low dryer temperature. Measure the resistance of each thermistor then refer to the tables below. Replace the thermistor if the resistance reading doesn't comply with the table.Let
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