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Parts for Maytag MDET236AYW Dryer - AppliancePartsPros.com

Which thermostat did you replace?
The cycling thermostat is on the blower.
The hi-limit thermostat is at the heater.

Did changing the heat selection actually change the heat in the unit?

The first thing to check is that the vent system is OK.
Next check that the heating element is not grounded.
Unplug the unit and both wires to the heating element.
Measure across the element most are in the 8 to 12 ohm range.
Then measure from each element connector to ground/frame, both should be infinite ohms.
If not the element is grounded and should be replaced.

The fuse etc. should last till there is a problem with the vent or the unit.

Note that the fuse is a backup safety for the hi-limit thermostat which is also a safety device. The hi-limit should not open unless there is a problem elsewhere. If the unit starts regulating the temperature by using the high limit then the high limit thermostat will fail after some time as it's contacts are not made to continuously switch the current on/off unlike the cycling/operating thermostat.