These appliances certainly increase the number of things allowed down the drain, but they’re not foolproof. There are several items you shouldn’t put in your garbage disposal, according to manufacturers and technicians. Don’t put coffee grounds down the drain. The same goes for eggshells, potato peels, hard foods, onion skins, and any dry, expandable food. Most importantly, never put grease or oils down the drain.

Replacing a garbage disposal costs anywhere from $150 to $950, but the average cost is somewhere around $550. There are two types of garbage disposal units, and continuous feed disposals tend to cost more than batch feed disposals. Going for an aluminum garbage disposal is also significantly cheaper than choosing a stainless steel garbage disposal. You'll also need to factor in the horsepower of the motor, labor, and the removal and disposal of your old unit.

Whether it's worth repairing your garbage disposal depends on its age and the specific problem. Generally, if the unit is eight years old or younger, repair is a good option. For minor issues like a bad seal or a simple jam, a repair can be inexpensive, sometimes under $10. However, if the motor is broken (a repair that can cost $150 or more) or the unit is getting old, it's often more cost-effective to replace the entire disposal.

There are many maintenance and repair issues that lead to a malfunctioning garbage disposal. Regular clogs place wear and tear on the motors, leading to an eventual shutdown. Electrical issues at the breaker, wall outlet, or disposal itself can fry the unit. The most common cause is simply a worn-down motor. These motors can only handle so much use before powering down for good.