Assuming the drum is turning, here is what you want to check out.

1. Check the connection block to see that you are getting 120v to each side.

Then unplug the machine and

2. check each of the thermal fuses/thermostats.

3. Check the heating element for resistance.

If one of the thermostats/fuses is bad I suggest replacing all. Also, the important thing is to thoroughly clean the machine, particularly inside the internal venting from the lint filter on out and the external vent.

Here is a service manual that will show you how to get into it.

http://frigidaireservicetips.com/pdfs/488_3.pdf