HI. This will essentially be an issue that concerns the gas valve coils. With that said, I will post below a complete burner assembly procedure that will help you isolate the culprit. I'm sure that the coils will fail the test, but to be safe, follow the procedure to confirm.
Gas valve/Burner testing procedure:
On the gas valve are one or two coils (solenoids) used to open and close the valve to control the flow of gas. If a coil fails, gas will not flow and the dryer will have no heat.
The easiest way to diagnose a problem in the burner assembly is to observe the burner operation. Remove the small access panel at the bottom, front of the dryer, select a high temperature setting and start the appliance. Watch the burner assembly, shortly after starting the dryer the ignitor should begin to glow. Next you should hear the click of the gas valve coil and a flame should ignite. The flame should be mostly blue and it should remain on for a minute or more.
If the ignitor glows for several seconds (up to 15 seconds) and then goes out, the problem is probably the coils (solenoids). If the ignitor glows and stays on, then the problem is usually the flame sensor. If it ignites and then quickly goes out, it is most likely a problem with inadequate air flow.Test the coil for resistance using a multimeter. Set the multimeter to the ohms setting X10. Place a probe on each terminal. The multimeter should change from a reading of infinity to roughly 1300 ohms (+/- 150 ohms) when the probes touch the terminals. If the reading is infinity or substantially different from 1300 ohms, the solenoid should be replaced.Click Here to access a exploded diagram of the burner assembly.
The affected coils will be labeled number 15 and 10. The actual coil and valve assembly will be labeled number 11 and the burner will be labeled number 9