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Replacement parts for WHIRLPOOL LE5750XMW1 Residential Dryer | AppliancePartsPros.com

See the attachment for your wiring diagram.

To be absolutely sure that the vent system is not the problem:
Unplug the unit and disconnect it from the vent system.
Now try a run.
If it now dries OK odds are the vent system needs additional checking.
Be sure to check that the louvers on the outside of the house open correctly.

If you do not want any lint in the house.
Take a pair of pantyhose.
Put one leg into the other and then attach this to the dryer's vent.
Leave enough room so the pantyhose can balloon out like a windsock.

Both the above will let you check the temperature and the air flow.

Note: The above is not recommended for gas dryers due to carbon monoxide concerns.

If it still does not dry properly.
If you have a thermometer check the exhaust temperature.
It should get up to about 130 degrees F or so.
This depends on it's setting. See item 19 in Section 4 and it shows that the thermostat is adjustable from 135 to 155.

If temperature is low check the heating coil.

Unplug the unit and both wires to the coil.
Check it with a meter, should be around 10 to 12 ohms.
Then check from each side of the coil to the case/frame, both should be infinite ohms (open). If not the coil may have sagged or broken and is touching the case. This can cause it to run at a ;low temperature all the time.

If coil is OK.
Unplug the unit.
Disconnect the AH2 wire at the timer.
Measure across the AH2 contacts when in a high heat mode.
They shpould be open (infinite ohms).
Perhaps the unit is always in low heat.

If the air flow is not strong then check the lint filter.
Sometimes they get coated with fabric softener residue and greatly reduce the air flow.
If it is coatred clean it with soap and water.
Check that the blower wheel is properly attached and is clean.