| || Belt |
Some dryers have drive belts that are used to turn the drum. If this belt becomes worn and breaks, it will no longer prompt the drum to tumble. Open up your dryer's cabinet and inspect its belt. You will have to replace a belt that has become defective in order for your dryer to tumble again. Also, take a quick look at your idler pulley wheel. Pulley wheels tend to wear at the same rate as a dryer's belt, and it may also be in need of replacing.
| || Motor |
If your dryer's motor is defective, your dryer may not tumble. Open up your dryer's cabinet and test its motor. If you discover that it is in fact malfunctioning, replace it.
| || Idler Pulley Wheel |
Oftentimes a dryer's idler pulley wheel wears at the same rate as the dryer's belt. So if you need to replace the belt, you likely need to replace the idler pulley wheel at the same time. It is possible that your belt is fine, but the pulley wheel has become defective. Open up your dryer's cabinet and conduct a thorough inspection of your idler pulley wheel. If need be, replace it.
| || Door Switch |
If your door switch is defective, it may interfere with your dryer drum's ability to tumble. Test your dryer's door switch. If it is no longer functioning as it should, replace it.