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Replacement parts for Whirlpool LER8620PW0 29"ELECTRIC DRYER | AppliancePartsPros.com

Unplug the unit and remove the rear panel and both wires to the heating coil and check it with a meter. Should be around 10 ohms. Also check from each heater connector to the frame, both should be infinite ohms.

If the heater is good check the thermal cut-off. It should be 0 ohms.
If it is open (infinite ohms) then the heater may have blown it that is why you check the heater to the frame (ground) just to be sure that it is not grounded.

But before doing the above I would do the following as the heater requires the full 240 volts but the motor runs on half the line (120 volts)

Try flipping the breaker off/on slowly a couple times. Sometimes you can loose half the line without actually tripping the breaker.
Check the voltage at the plug
L1 to L2 should be 240 volts
L1 to Neutral and L2 to Neutral, both should be 120 volts.
If OK
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
Do this with the heater off and on.
[COLOR="Red"]Be careful as 240 volts is lethal !!![/COLOR]