How-To Install a Garbage Disposal

A step-by-step tutorial on replacing or installing a garbage disposal in your kitchen, covering everything from preparation to testing for leaks.

Replacing or installing a garbage disposal can seem like a daunting task, but it doesn’t have to be! 

If you follow this easy tutorial, you’ll be disposing of your kitchen waste in a jiffy. 

Let’s dive in.

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STEP 1: Prepare for Installation

Before you even think about installing your new garbage disposal, take some time to prep the area.

First, ensure you have a catch basin for water, a wrench, and a screwdriver.

Unplug the old garbage disposal unit. 

SIDE NOTE: Some prefer to turn off the main power to be extra safe.

To avoid any waterworks midway through, turn off the water supply to your sink.

STEP 2: Remove the Old Garbage Disposal

Out with the old, in with the new by removing your old disposal.

Locate the P-trap under your sink. Place your catch basin under the p-trap and disconnect it carefully because some water will spill, but that’s why you have a catch basin ready.

Depending on your specific model, you may need to unscrew or unclamp your old disposal from the sink flange.

Once disconnected, simply lift out the old disposal unit.

Next, loosen the screws holding the flange tight to the sink. 

Afterward, you can remove the metal ring holding the flange system into place. 

Remove all the old fittings from the sink base and clean the sink for the new system.

STEP 3: Install the New Sink Flange

Installing the sink flange properly is crucial for a leak-free experience.

Depending on your specific sink and new garbage disposal, you can use a rubber washer for the part inside the sink (usually only used for a stainless steel sink).

Instead of the washer, you need to use Plumber’s Putty, like I did, to give you a secure seal. 

Installing the putty like you would Play-Doh to create a seal around the new flange is easy.

Place the sink part into the sink and press it into place.

Secure the rest of the flange in place using the screws and metal ring. Tighten using a hex wrench (which should have come with your disposal) until it’s firmly in place.

TIP: It’s a good idea to test for leaks. Use a stopper to plug your sink and fill it with a few inches of water. If you notice no leaks, you are ready to move on. If you see leaks, tighten the screws on the flange more. 

STEP 4: Make Room for the Dishwasher Drain

If you have a dishwasher, you must prep your new disposal unit for it.

On your new disposal, find the dishwasher drain hole.

Carefully knock out this hole with a flathead screwdriver and hammer so that you can attach your dishwasher’s drain pipe later.

TIP: Remove any debris from the hole after knocking it out.

STEP 5: Attach the Fittings on the Garbage Disposal

Time to connect the fittings onto the garbage disposal for the drain and dishwasher drain connector.

Follow your unit’s instructions to assemble the drain and dishwasher connector.
Don’t Over-Tighten. Since these parts are usually plastic, ensure not to over-tighten and risk breaking them.

STEP 6: Install the Garbage Disposal

Fit your new garbage disposal unit into the flange.

And tighten into place.

STEP 7: Final Touches

Now that the garbage disposal is secured in place, it’s time to reconnect the drain lines.

Attach the drain line back to your sink by reinstalling the p-trap.

Don’t forget to reconnect the dishwasher drain line if you have one.

Plug in your new garbage disposal or turn the power back on.

STEP 8: Test for Garbage Disposal

Before you celebrate, let’s make sure everything is tight and right.

Release the water that you should have in the sink from your first water test and check if any leaks appear.

If you notice any leaks, tighten the respective connectors and test again.

It’s time to turn on your new garbage disposal and test it out. Make sure everything runs smoothly. 

FULL PROJECT VIDEO:

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Congratulations! You’ve successfully installed your new garbage disposal. Now, go ahead and dispose of your kitchen waste like a pro!