Garbage disposals are electrical appliances, which means there’s a live current running through them at all time while the power is on. Make sure that the water is cut off to your garbage disposal, too. [2] X Expert Source Patrick JohnsHome Improvement Specialist Expert Interview. 26 October 2021.
Take note of the make and model of the disposal. Replacing it with a similar model will be as easy as removing the existing unit and screwing on the new one.
The discharge tube is responsible for carrying ground food waste out of the disposal. Some older garbage disposals are also connected to the dishwasher water supply via a second tube. This one can be disconnected in the same manner. [4] X Research source
Garbage disposals tend to be surprisingly heavy (some can weigh as much as 15 pounds!), so be ready to catch and hold the unit once it comes away from the mounting ring. It may be a good idea to place a couple paint cans, some wood scraps, or a stack of phone books beneath the disposal to act as a support platform. [6] X Research source
A pair of needle-nosed pliers may come in handy for releasing wire connectors that are too small to unclip by hand.
If there’s a separate gasket sandwiched above the mounting ring, be sure to remove it as well. Consider keeping your current mounting hardware if it looks to be in good shape. This will make installing the new disposal much quicker and easier. [9] X Research source
You may have to apply a considerable amount of force to undo a mounting nut that’s had years to settle into place. If you’re having trouble getting it to budge, try pushing the handle of the screwdriver with both hands rather than pulling. You’ll get better leverage this way.
If you see any dry, crusted remnants of plumber’s putty where the flange sat, use a putty knife to scrape it off. [12] X Research source Pat the drain opening dry with a clean towel before attempting to use adhesive to secure the new flange.
Use a heavy object, such as a toolbox or the old garbage disposal unit, to keep constant pressure on the new flange until the adhesive has had time to fully dry. This may take anywhere from 10-20 minutes, depending on the specific product you’re using. The added weight will also prevent the flange from shifting as you install the new unit. [14] X Research source You also have the option of using silicone sealant in place of traditional plumber’s putty. Many home improvement experts claim that silicone has a stronger hold and provides a longer-lasting watertight seal.
Jiggle the new mounting assembly gently from the bottom to make sure it’s secure.
At this point, you can remove the weight you’ve been using to hold down the new sink flange.
Most garbage disposals only have 2 sets of connections—a pair of red wires and a pair of white or black wires. Any additional wires should also be color-coded for convenience. This will make putting them back together a breeze. [18] X Research source For your own safety, it’s critical that the main power to the disposal remain off throughout this process.
For flexible hose connections, consider using a separate metal clamp to cinch the discharge tube to the disposal valve.
If the discharge tube is too short to accommodate the new unit, you’ll need to make a trip down to your local home improvement store to pick up a new one with the appropriate dimensions.
Patch up any minor leaks you find using a strip of thread seal tape or a line of Teflon pipe joint compound. [22] X Research source Before tackling a leak, don’t forget to dry off the plumbing fixtures so that the adhesive will be able to stick.
Double check that you haven’t left any tools, screws, or other stray pieces in the sink. You don’t want them to fall down the disposal! If the new disposal is making unusual noises or doesn’t seem to be operating correctly, call a professional plumber and have them take a closer look at it. There may be an issue with the inner mechanics of the unit itself.
