If your dryer does not work at all, here are some things to check: the power from the house, door switch, thermal fuse, and the wiring. First, check to see if there is power going into the dryer. Is it even plugged in? Try plugging something else, like a lamp, into the socket. Does it work? Of it doesn't check for a tripped circuit or a blown fuse. Next, you can check the door switch. The switch is inside the dryer housing near the frame of the door. You might have to open the top or front of your dryer to get to the switch. If it is defective you should replace it. You should also check the thermal fuse. On many dryers there is a thermal fuse. This fuse is meant to blows if the dryer overheats. It is mounted to the exhaust duct, often inside the back panel. If the fuse is blown, it won't have continuity. You cannot reset a thermal fuse, and if it has blown you will need to replace it. Next, you can check the wiring connections. Sometimes the wiring connection from the house at the dryer burns and the connection breaks. If this is why your dryer isn't working you will need to replace the power cord and also the terminal block inside of the dryer.Now, here is how to troubleshoot an electric dryer that has no heat. First, check the power outlet like how I explained in the above paragraph. You can also check the heating element. If a heating element burns out, often times it doesn't trip a circuit or blow a fuse. The heating element can be tested for continuity with an ohm meter. If it has no continuity it means the element is bad and you will need to replace it since a heating element from an electric dryer cannot be repaired. You can also check the thermal fuse and the wiring just like I explained above.
Okay, so here is how to troubleshoot an electric dryer that won't tumble. You will need to check the belt, motor, and door switch. In a dryer, the belt turns the drum. If your belt breaks, the drum will stop turning. You will have to replace the belt, and while you are there you should also replace the pulley - they tend to wear out at the same time. If your dryer motor hums when you push the start button, your motor may be burned out. I'll explain how to test the motor. First remove the belt, then check the blower fan housing for any blockages or obstructions, then try to manually rotate the shaft of the motor. If you cannot rotate the motor, or if it is stiff, and there is no obtrusion in the fan, then you will need to replace the motor. However, if the motor does spin freely, run the motor with the belt removed. If the motor runs okay without the belt, there could be a problem with your idler pulley or drum. Try rotating the drum by hand. If it is hard to move, correct any problems with the rollers or pulley. Then reassemble the dryer and try it once more. If your motor hums but it does not move on its own, even if the belt is removed, but you can turn it by hand, you need to replace the motor. If your door switch is bad then your dryer won't operate. This switch is located inside the main dryer housing near the frame of the door. If it is defective, replace it.
Next, I will explain how to troubleshoot an electric dryer that seems to run forever. Usually this is caused by a clog in the venting, or a clog in the duct. If your dryer has an automatic cycle that turns the dryer off when the clothes are dry, it does that using a special type of thermostat or a moisture sensing system. I'll explain what happens during your dryer's automatic cycle. The thermostat tells your dryer to heat up until the inside of the dryer reaches a certain temperature. Once the dryer reaches that temperature, the thermostat tells the timer to start advancing. The timer advances until the inside of the dryer cools down. Then the thermostat tells the timer to stop and tells the dryer to start heating up again. This cycle will continue until your clothes are dry. However, if your vent is clogged the dryer might never reach that specific temperature, so the timer does not get the signal, and the dryer will run forever. Even if the clothes are dry. To fix it: clean out the venting, and also clean the inside ductwork.