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Parts for Estate EED4400WQ0 Dryer - AppliancePartsPros.com

See the attachment for the wiring diagram.

The first thing to check is the power.
The heating element requires the full 240.

Try flipping the breaker off/on slowly a couple times, sometimes you can loose half the line without actually tripping the breaker.
If this does nothing, 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.
[COLOR="Red"]Be careful as 240 volts is lethal !!! [/COLOR]

I am assuming that you checked for the 240 volts and it was OK even though you did not specifically say this.
Also that when you checked for the 120 at the thermostats ypou were using Neutral/ground as the reference.

Was the unit running when you got the 120 at the thermostats etc.?
OR
Was the unit not running but the timer was set to a heating cycle?

Using 120 can be confusing when checking the heater circuit.
Neutral/ground is not be part of the heater circuit.
It is L1 to L2 or 240 volts.

I will try to explain this.
L1 should always have 120 volts on it when referenced to Neutral/ground.
This also applies to L2.
So if the timer is on a heat cycle, A to B timer contacts are closed.
Therefore if the reference side of the meter is Neutral then you will see 120 volts at B on the timer, at A on the timer, at both sides of the thermostats and the heater.
There is no circuit path for the current so there is no voltage drop across any component.

Since the dryer is not running this is what you would expect.

When the dryer is running the centrifugal switch (1M/2M) on the motor closes when the motor gets close to operating speed.
This then connects L2 into the heater circuit and the heater heats up.

Note: with the motor running you will still see 120 volts at all the places you checked. The difference is that at the heater you are seeing L1 voltage on one side and L2 voltage on the other side if the unit is working correctly.

Sounds like either there is a bad connection or the centrifugal switch is not closing.

I doubt this is is a heater problem.

I do not know how much you know about electricity so perhaps the below will be helpful.
Your house electrical is actually two 120 volt supplies (L1 and L2) that share a common Neutral/ground.
they are 180 degrees out of phase.
in other words when one is at positive 120 volts, the other is at negative 120 volts.
So the difference between the two is 240 volts and this is what runs the heating element.

[COLOR="Blue"]So you believe my problem is in the timer switch?[/COLOR]
No.
I think the problem is in the circuit from the right hand side of the heating element (using the wiring diagram) and the connection to L2.
So it is either a bad wire or a problem with the centrifugal switch.