The Most Common Garbage Disposal Problems
Garbage disposals fail in a few predictable ways, and understanding which type of failure you’re dealing with determines whether it’s a quick self-fix or time to call a plumber. The most common issues are: the disposal won’t turn on at all, the disposal hums but the grinding mechanism doesn’t spin, the disposal makes a grinding noise and then trips off, the disposal leaks water, or the disposal drains slowly.
Each of these has a distinct cause, and most of the non-leak issues can be addressed without any tools or plumbing experience. The leak scenarios vary more — a leak from the top of the disposal is usually a mounting gasket issue, while a leak from the bottom typically means the internal seals have failed and the unit needs replacement.
DIY Fixes That Work
If your disposal won’t turn on at all, start with the reset button on the bottom of the unit. Disposals have a built-in thermal overload switch that trips when the motor overheats or is overloaded. Press the red or black button until you feel it click in, then try the switch again. If there’s no power to the unit even after resetting, check the outlet it’s plugged into — often under the sink — and check your circuit breaker.
If the disposal hums but doesn’t grind (the motor is running but the grinding plate is jammed), turn it off immediately. Use the hex wrench that came with the unit — or a standard 1/4-inch Allen wrench — in the hex socket at the bottom center of the disposal. Manually turning the plate back and forth usually frees the jam. Never put your hand in a disposal.
What You Should Never Put Down a Disposal
A significant number of disposal service calls and replacements are caused by putting the wrong things through the unit. Fibrous vegetables like celery, artichokes, and asparagus can wrap around the grinding mechanism and jam or damage it. Starchy foods like pasta, rice, and potato peels expand with water and create thick sludge that clogs the drain line.
Bones, fruit pits, and shellfish shells are too hard for residential disposals and will dull or break the grinding components. Grease and cooking oil shouldn’t go down any drain, but the disposal is particularly bad — the warm water running during use liquefies grease and pushes it further into your pipes, where it cools, solidifies, and builds up into a clog. Run cold water when using your disposal, not hot.
When to Replace Rather Than Repair
Disposals typically last 8-12 years. If yours is leaking from the body (not a fitting), makes persistent grinding noise even when empty, has a cracked housing, or is electrically unreliable, replacement is usually more cost-effective than repair. Labor costs for a disposal repair can approach or exceed the cost of a new mid-range unit.
Replacement is a straightforward plumbing job for a licensed plumber — typically completed in an hour. If you’re doing a kitchen renovation or replacing the sink simultaneously, it’s a logical time to upgrade to a higher-capacity unit with better noise insulation.
Related Services
Get Disposal Help
Whether you need a disposal repaired or replaced, Advantage Air Plumbing, Heating & Cooling can handle it quickly. Contact us to schedule a plumbing service call.
