Our electric Whirlpool Imperial Series dryer tumbles but won't heat. We purchased it used and it worked great the first couple weeks. I seem to remember that it was taking longer to dry the last few times--but I am not confident about this. The circuit breakers for the dryer are not tripped. We have used an Ohmmeter to check the heating element, thermal fuse, and power cord. All of these go to "0" when tested. Are there other fuses or things we can and should check? What else might be wrong? Please help us make a diagnosis! Thanks much.