Installing a Garbage Disposal

Written by Lee Wyatt (last updated December 4, 2020)

Whether you already have a garbage disposal that needs replacing, or you are looking to install one for the first time, it never hurts to know the proper methods for installing a garbage disposal. Installing a garbage disposal isn't all that difficult of a task, though it can take a bit of time for the do it yourselfer who is just starting out. At most, this project should only take you half of a day if you follow these directions.

  1. Check for space. Before you can actually install a garbage disposal you need to make sure that you actually have the space for it. This means that you will need to look under the sink, take everything out, and then get some measurements. Take those measurements to your local home improvement store, and get a disposal that will fit within those dimensions.
  2. Disconnect power and water. After you have the model of disposal that you want, take it home and begin the installation process. To begin with you need to shut of the power to the kitchen by turning off the power at the circuit breaker. Furthermore, you also need to remove the existing drain lines. You will also want to place a rag or something in the main drain to help prevent any leaks. Look at where the drain and the pipes meet, and remove the large nut. Once you have done that you can actually remove the strainer, or drain, body from the bottom of the sink by pushing the strainer body carefully.
  3. Remove the old putty. Using a putty knife, or even a screwdriver, remove all of the putty that you find around the opening in the sink. Be prepared to do a bit of scrubbing with a wash rag and a green scrubby to help ensure that you remove all of the putty from the opening. Once you have done that, take a look at the mounting assembly. Grab a screwdriver and loosen all of the screws until you can reach the snap ring.
  4. Get rid of the snap ring. Take a screwdriver and pry the snap ring off of the sink flange. Once you have done that, the mounting assembly should be able to come apart fairly easily. As you are taking everything apart, be very careful that you do not damage the gasket, and that you don't lose anything.
  5. Apply some new putty. Roll a bunch of plumbers putty into a rather long snake, and press it firmly into place around the opening. Once you have done that begin putting the mounting assembly back together.
  6. Slip your mounting ring over the flange. You will need to hold the gasket and backup ring in place while you slip the mounting ring over the sink flange. You can very easily hold all the pieces together using a rubber band (a wide one), just make sure that you place the rubber band above the snap ring groove.
  7. Install a new snap ring. Slide the new snap ring by sliding it up the sink flange. Continue to slide it up the flange until it snaps into place in the groove. Once you have done that, you can then remove the rubber band, and wipe up any putty that may have been pushed out of the flange.
  8. Knock and pull the plug. Take a look at the disposal unit, and grab a flat headed screwdriver. Identify where the plug is located, and then begin knocking it back into the unit. Turn the unit back upright, and then remove the gasket and ring. Once you have done that all you need to do is turn it upside down again, and then remove the plug. With the plug removed, you can then replace the gasket and ring. Take the time to locate the electrical hole, and when you find it insert a wire clamp if one is not there.
  9. Remove the access hole cover. Look at the bottom of your disposal unit, and see if you can locate the access hole. Most access holes covers are held in place with a single screw, so identify which one it is, and then remove that screw. With the cover removed, pull out the ends of the wires so that you can begin connecting them.
  10. Connect and store the wires. Use the wire clamp to hold the electrical wire, and begin connecting the wires in the access hole. As you are connecting the wire, make sure that you are matching the colors (i.e., black to black, and white to white), and that you are using a wire nut to connect the wires together. You may also want to wrap the wire nuts (and thus the wires) in some electrical tape to add a bit of extra security. Do not forget to connect the ground wire as well. When you have finished connecting the wires, plush them back into the access hole, and secure the cover of the access hole. Furthermore, you will want to tighten the electrical clamp down as much as you can, but do not damage the wires.
  11. Mount the system. Begin mounting the disposal system to the mounting ring that you assembled earlier. Follow any specific mounting instructions that came with your unit, but typically you only need to insert the top end of the mounting gasket into the mounting assembly. When you have done that, simply turn the mounting ring right until the tabs feel secure. Use adjustable pliers to lock the tabs over the ridges.
  12. Install the drain lines. Begin installing the drain lines by first attaching the tailpiece and trap arm. Insert the discharge tube into the T-fitting, but do not completely tighten the slip nut. Insert the opposite end of the discharge tube into the disposal system, and then use a screwdriver to secure the metal flange with the bolt that came along with the disposal system. When you have done that, go ahead and tighten all of the slip nuts.
  13. Finish off the installation. Finish off the installation of your garbage disposal by slipping the bell over the disposal drain, then clamping it down. Chances are you will need to use a screw driver to finish clamping everything down so be sure that you have one of both types on hand to ensure that you can get the job done properly.

Once you have finished the process of installation, you still need to do a bit of testing. Testing is rather simple, in that you simply need to run the water and the disposal. As long as it is running, and there are no leaks, you are pretty much done. All that you have to do after successfully installing and testing the garbage disposal is clean everything up.

Author Bio

Lee Wyatt

Contributor of numerous Tips.Net articles, Lee Wyatt is quickly becoming a regular "Jack of all trades." He is currently an independent contractor specializing in writing and editing. Contact him today for all of your writing and editing needs! Click here to contact. ...


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