How to Install an In-Sink Air Switch for a Garbage Disposal

The first and most critical step is to ensure your safety. Go to your home's main electrical panel and turn off the circuit breaker that supplies power to the garbage disposal outlet. Return to the kitchen and use a non-contact voltage tester to verify that the outlet under the sink is completely dead. Once safety is confirmed, clear out all items from the cabinet under the sink to create a clean and accessible workspace. Place some old towels or rags on the cabinet floor to catch any water or debris.

Choose a suitable location for the air switch button on the sink deck, typically opposite the faucet handle. Ensure there's clearance underneath. Use a tape measure and marker to mark the center of the hole. For a stainless steel sink, use a center punch and a hammer to create a small indentation at the mark; this prevents the drill bit from wandering. Start by drilling a small pilot hole with a 1/8-inch drill bit. Then, use a step drill bit or a metal-rated hole saw of the correct diameter (typically 1-3/8 inches, but check your air switch kit instructions) to enlarge the hole. Apply cutting oil to lubricate the process and keep the metal cool. Once the hole is drilled, use a deburring tool or a small metal file to smooth any sharp edges around the hole's perimeter.

Take the air switch button assembly from your kit. Typically, it consists of the decorative button top, a gasket, the main body, and a retaining nut. Unscrew the retaining nut from the body. From the top of the sink, place the rubber or silicone gasket over the hole, then insert the main body of the air switch button through the gasket and the hole. From underneath the sink, thread the retaining nut onto the switch body and hand-tighten it. Use a pair of channel-lock pliers or the plastic wrench that may be included in the kit to give the nut a final quarter-turn to secure it firmly, being careful not to over-tighten.

Locate the power control module from your air switch kit. This is the small box with a power cord and an outlet on it. First, unplug your garbage disposal's power cord from the wall outlet under the sink. Then, take the power control module and plug its cord into that same wall outlet. The module is now the intermediary between the wall power and the disposal.

With the control module plugged into the wall, now plug the garbage disposal's power cord directly into the switched outlet on the control module itself. Next, take the flexible vinyl or rubber air tube. Firmly push one end of the tube onto the small air nipple extending from the bottom of the air switch button you mounted. Take the other end of the air tube and push it firmly onto the corresponding air nipple on the power control module. If the tube is excessively long, you can trim it to length with a utility knife, but leave some slack to avoid kinks.

The installation is now complete and ready for testing. Go back to the electrical panel and turn the circuit breaker back on. Return to the sink and run cold water into the drain. Press the newly installed air switch button once. You should hear a faint click from the control module and the garbage disposal should turn on. Press the button again to turn the disposal off. If the disposal does not turn on, double-check all connections: the module in the wall, the disposal in the module, and both ends of the air tube. Once functionality is confirmed, clean up your tools and put all items back in the under-sink cabinet.