I have a Whirlpool Inglis dryer that suddenly wont heat up. Also the timer is not working allowing the dryer to keep running unless the knob is manually turned to the off position. Both problems happened at the same time. I know the problem is not the breaker/voltage because I just had that checked. Also, we ordered and installed a new heating element and this did not solve the problem. Could this be a thermostat problem? Or perhaps a timer issue?

Thanks for the reply. I need to buy one of those voltage indicators. Would come in really handy with this dyer. Wouldn't a bad motor switch cause the dryer not to tumble though? Forgive me, I don't have too much experience fixing them. Any other suggestions?

See the attachment for your wiring diagram.

As fairbank56 said it is important to check if the timer does not advance in both timed dry and auto modes.
As you can see from the wiring diagram the timer motor gets power through different paths depending on cycle type.

Note that both the timer and the heater run off of 240 volts.

If both modes do not advance it could be a bad heater centrifugal switch on the motor, no 240 volts or a disconnected/bad connection wire either in the wires in the unit or the line cord.

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]