I want to keep this old Whirlpool because the quality of similar new ones is so shoddy. It runs but won’t heat. I looked at the instructions on your site, and the unit has 240V at the plug. It most likely is the heating element. Since I have to pull the thing out of the room and take off the back cover, and the key replacement parts are inexpensive, wouldn’t it be smart to replace the heating element and all of the thermostats? Should I also replace the original belt? Please give me prices for these parts, and any others besides the switch located in the motor.
Use a meter to test the thermostats, if one is bad replace them all. If the heating element tests ok, I would leave it alone.
While you have it open you should clean it out thoroughly, including the lint chute. I would also change the belt and pulley.
Do this and you should be all set.