I have a 70 series kenmore electric dryer that will start and spin, but I get no heat. This was a sudden thing

if you can use a simple voltmeter you can troubleshoot that one. remove the back. there is a heating element. test it...it should show continuity. if not, that's the problem. there are at least 3 therm-switches back there, maybe 4. unplug them and test...they also should show continuity when the dryer is off. you can get your parts at any appliance supply store. it's actually a Whirlpool. Sears is the last place to buy the part...stupidly expensive.