Garbage Disposal Leaks 101

There are common causes for garbage disposal leaks – usually it’s a minor component being too loose or worn out. By finding from where your garbage disposal is leaking, you’ll be able to figure out why it’s leaking! And then you can fix it.

If your garbage disposal is leaking, it will likely leak from one of these places: the top, the pipe connections and the bottom. To find out if your disposal is leaking, check each common place where leaks start. Start with a flashlight to check for puddling, condensation, and other signs of water accumulation around or under your disposal.

So let’s find out what’s going on with your disposal.

Garbage disposals usually leak from four different places:

  1. The reset button (on the bottom of the disposal) – deactivates the disposal if it jams or the motor overloads.
  2. The dishwasher hose connection on the side of the disposal – where the flexible plastic dishwasher hose connects to the disposal.
  3. The sink flange – located at the top of the garbage disposal; connects the disposal to the top of the sink.
  4. The drain line connection – where the main drain pipe connects to the disposal via curving metal or PVC plastic pipes.

First, look for the obvious signs of garbage disposal leaks.

  • If you see any signs of leaking, check that it isn’t the sink itself or the sink’s p-trap. If not, check under your kitchen sink for puddling water, dampness, dripping or a musty smell. Grab a flashlight and bucket to look for each type of leak.
  • Turn off the garbage disposal and unplug it.
  • Then, fill up the kitchen sink with water about halfway. Add food coloring to the water so you can spot the leak.

You can locate the leak in the following ways:Woman holding a wrench checks for leaks under her kitchen sink

  • The reset button: The reset button is located in the bottom of the disposal unit. Check for a slow, constant drip or water accumulation under the unit.
  • The dishwasher hose connection: Start the dishwasher without turning back on the disposal. Watch the hose as the water runs from the dishwasher drain through it. Pay attention to the connections between the hose and disposal.
  • The sink flange: Check for dripping or accumulating water around the top and bottom of the ring of the flange. Use the flashlight to look for water coloring and feel for wetness.
  • The drain line connection: Check the drain line and disposal connection. Pay attention to the screws that fasten the line to the disposal and to the gap between the disposal and drain line.

If you find a leak at any of these points, find out why.

Each of the four common leaks have different causes and fixes. Here’s how to locate what caused it:

  1. The reset button: If your garbage disposal is leaking from either the reset button or at the bottom of the disposal it probably means a seal inside the unit has worn out. This can happen when a garbage disposal gets old.
  2. The dishwasher hose connection: If the dishwasher hose is leaking, it’s usually because the screws have loosened. This can happen because of rust or age. It’s also possible the drain hose or clamp are leaking.
  3. The sink flange: This part is held in place by plumber’s putty and bolts. The putty can deteriorate or the bolts rust or loosen, and the watertight seal between the flange and sink may break.
  4. The drain line connection: If the drain line is leaking, then either the screws have worn out, or the rubber gasket inside the assembly is leaking. Take down the drain line and check the gasket for wear and tear.

Now that you’ve identified the where and why, you’re ready to fix the problem.

The good news is fixing a leaking garbage disposal is usually straightforward, even when you might need a professional:

  1. The reset button: Unfortunately, if your garbage disposal leaks from the bottom it’s probably time to replace it.
  2. The dishwasher hose connection: First, try to tighten the screws on the metal clamp connecting the hose to the disposal. If the screws don’t tighten properly, replace them. If the hose is also leaking, you’ll have to replace it, too.
  3. The drain line connection: Try to fix this leak by tightening the connection between the pipe and disposal. Detach and reattach the pipe if tightening doesn’t work. If there are still issues, replace the screws or gasket.
  4. The sink flange: Unscrew and check the bolts for rust or other deterioration and replace them if needed. Then, remove the flange, scrap off the putty, and reapply new putty. Turn back on the water to test the seal.

Using these instructions, you should be able to identify and fix nearly any garbage disposal leak! Of course, sometimes unusual leaks happen. They can be tough to figure out, much less fix, so contact a professional in those situations. If you need the assistance of a licensed plumber, then call Central Carolina Air Conditioning, Plumbing, & Electrical at 800.461.3010.