Installing a Garbage Disposal
If the sink you are working with has not had a disposal previously, you will need to remove the drain and replace it with the one that comes with your disposal that allows you to attach the disposal under your sink. On a new sink, with everything easy to access because it’s not under the sink, this is a breeze. Sometimes getting the old drain to let go can be a chore. Once the drain has been replaced, you are ready to install your unit.
If you are replacing an old disposal, you will need to remove the old unit first. To do this, first turn off the power to the unit at the breaker or fuse box. Then, remove the plate on the bottom or side of the unit that covers the wiring. Usually, one or two screws have to be removed to do this. Pull the wires outside of the the disposal and remove the wire nuts so the wires can be uncoupled.
Once the wires are loose, you need to unscrew the large nut that attaches your drain pipes to your unit. If you have a dishwasher installed, normally a clamp has to be removed to allow the dishwasher drain to be taken off of the disposal. When these three connections have been removed, you should be able to turn your disposal clockwise by gripping it tightly with both hands. You may need to apply some upward pressure. By turning the unit, the notches that secure it should align with the tabs on the drain and allow it to drop down from your sink and be removed.
Compare the attachment area of the old unit with the new one. If they match, then all that you have to do is reverse this process. If they don’t, you may have to exchange the drain on the sink for the new one that came with your new disposal. You may want to do this anyway if your old drain is look beat up or marred.
Returning under the sink with the new disposal in hand, slide the unit up over the attachment area while aligning the tabs and slots. Once it has been pushed up until it is against the top of the drain, rotate it counterclockwise to secure it to the drain. Make sure by inspecting it with some a flashlight or work light that it has turned until everything is a tight as possible. There are some tightening screws in the attachment that can be adjusted if it is needed. If it is a new installation, you will need to adjust these to level and secure the unit firmly to the sink.
I recommend that you replace the drain pipes and trap at this time to prevent a future repair. Most old pipes aren’t very forgiving when they are loosened a refitted to new devices. Re-attach the drains to the unit for the sink and, if needed, the dishwasher.
Complete the wiring and replace the cover. Fill the sink with water before restoring the power. Check for leaks from the drain whether it was replaced or not. You may have created a problem by disturbing it. If all is dry, then release the water to check for leaks around the neck of the disposal where it attaches. Pay attention for leaks in your drain system.
If leaks are found, tighten the joints and test again. If your sink leaks when filled with water, try drying it and sealing it with some silicon. Allow this to completely dry. It sometimes take two or three tries to get everything sealed up.
Turn on the power and make sure the unit works. If it doesn’t, check the wiring instructions with the unit to make sure it was wired correctly. If that checks, then check all of your connections. Sometimes, when the wires are pushed into the unit, they can become unattached. If this fails, you may need to call a professional to check your work.
