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How To Install A Garbage Dispoal Yourself - Plumb University

How To Install A Garbage Dispoal Yourself

by Trevor Woods | Last Updated: February 28, 2020

We rely on garbage disposals in our kitchens a lot these days. They were originally designed by John Hammes back in 1927. And since then the design has remained more or less the same. However, its demand has grown with the passage of time to a point where now the sink disposal is considered to be an essential appliance in every kitchen. We will show you how to install a garbage disposal yourself and save money and protect your plumbing from food waste clogs.

In this guide, we will provide you with all the information that you need for a typical garbage disposal installation, how to properly use it, and some cleaning tips to prevent nasty odors.

But first, let’s see what a sink garbage disposal is and how it works!

What Is A Garbage Disposal?

A garbage disposer is also known as a waste disposal, sink disposal, garbage disposal, garburator, and many more synonyms. It is installed under your kitchen sink and runs on electricity. It’s installed between your sink’s drain and its trap and the garburator has the ability to shred food waste into tiny pieces (approximately 1/8″ or smaller). This shredding of the food scraps allows it to flow through your kitchen’s plumbing system uninterrupted and without causing blockages. 

History

In 1933, John Hammes applied for a patent for his invention that was eventually issued in 1935. And after a few years in 1940, his company InSinkErator launched his Garborator to the market.

During the 1930s and 40s, almost all the cities in the United States had municipal sewage system regulations that prohibited food waste in residential plumbing use. The prohibition was implemented because the general perception was that these disposers were a threat to the safety of a city’s sewerage system. 

But InSinkErator made some serious efforts to change that. They were very successful in convincing numerous municipalities in lifting the bans and as of 2009 half of American homes own a garbage disposal.

The Environmental Case For Garbage Disposals

Food scraps comprise 10% to 20% of the average household waste. They are problematic in municipal waste systems because they contribute to creating issues with public health as well as environmental and sanitation safety. This is primarily due to the difficulty in logistics and management of truck collection and waste storage.

A great deal of energy and resources are used to collect, store, transport, and dispose of food scraps. Not to mention, burying food waste in landfills to decompose them can lead to the generation of the greenhouse gas methane which can contribute to climate change over the long run. 

However, the high water content of food scraps lends itself well to being treated as a liquid. And for effective management, existing wastewater treatment facilities and infrastructure can be utilized. Garbage disposals can process food waste and send it down the drain to treatment facilities.

These treatment plants can transform these food scraps into biosolids for fertilizer products. And with the help of modern technology, extract methane for the purpose of energy production. Turning food waste into useable resources is cause for every home to consider installing a sink garbage disposal.

How Do Garbage Disposals Work?

A garbage disposer is installed under a kitchen sink. It collects all solid food waste in its grinding chamber. There is an impeller plate or spinning disc within this unit that will start rotating when you turn the disposer on. This disk has impellers that will force all food waste in the grinding chamber against the outer wall. 

The outer ring is equipped with a grinding or shredding surface and it will pulverize the food scraps into small bits. These virtually liquified bits will then pass through the holes present at the bottom of the chamber wall. The ground-up food is then washed away with water into the waste-pipe and through your plumbing system.

Leaving your home, the waste is transported to treatment plants or septic systems. Here it is treated for energy resources or composted properly.

Garbage Disposal Installation

Garbage disposal installation is pretty simple, but you need to have some basic plumbing and wiring skills up your sleeves. Most handy homeowners can install a new unit within a few hours without much fuss. 

Before you buy and start installing such a unit, make sure that you check all your local plumbing codes and regulations. Some communities prevent the usage of disposers due to their sewer capacity limits. Also, be aware of any local rules requiring you to have air gaps for a dishwasher with a disposal unit.

Tools And Materials Required 

How To

1. Disconnect The Old Plumbing

Start-off by making room for your new garburator by disconnecting the p-trap and the horizontal extension pipe. A large channel-lock plier or pipe wrench will make quick work of loosening the nuts that hold these pipes together.

Stay Dry

Use a small bucket or container to catch any water that is in the p-trap while you remove it.

When the connections are undone, remove the section of piping and set it aside. Be careful as the p-trap may be full of water! Now is a good time to inspect your pipes of any visible blockages and clean them out as necessary.

Now you get to choose which side you wish to mount your garbage disposal on if you have a double basin sink. Its common practice to install the disposal unit on the smaller sized bowl or on the side closest to the dishwasher.

Remove the large nut that holds the basket strainer on the side you wish to install the garburator and remove the strainer body.

2. Apply The Putty

Next you will want to clean up the old sink drain opening and get it ready for fresh putty. Once the surface is clean, use a flat-blade screwdriver to pry off the snap ring that is on the disposal mounting assembly if necessary.

Applying the putty is easy! Roll out a 1/2″ rope of putty and place it around the drain opening of the sink or on the underside of the mounting assembly drain flange. Drop the new flange assembly into the sink drain opening and firmly press it into place. Make sure to press it in evenly and get ready to install the backup ring along with the mounting ring and fiber gasket from the underside of your sink.

Why Use Putty?

You might be thinking about why to choose putty to seal the sink flange to the sink when silicone is available? Silicone may be more reliable and have a lesser chance of leaking but in most cases, silicone is messier and harder to clean up compared to putty.

3. Mounting Ring Installation

If you have an extra set of hands available, get them to hold the top of the sink flange down while you work below. If not, find something flat and heavy to act as a weight to hold the flange in place.

Save Your Sink

Avoid scratching your sink by placing a towel or something soft between the weight and the sink.

Finish installing the mounting assembly by sliding the fiber gasket, backup flange, and mounting flange over the sink flange and hold these pieces in place. Then slip the mounting ring on and push on the snap ring. Tighten up the mounting ring fasteners evenly by alternating screws every few turns until the mounting assembly is seated against the bottom of the sink.

At this point, any extra putty is going to ooze out from underneath the sink flange. Now is the perfect time to clean up the flange of the excess putty. A plastic putty knife works great but your fingernails will also do the job to scrape the surfaces clean.

4. Dishwasher Connection

If you are going to be running a dishwasher through the disposal, now is an ideal time to remove the dishwasher knockout plug. If you are piping the dishwasher through the plumbing drain line, skip this step.

Grab a hammer and screwdriver and lay the disposal unit on its side, careful not to scratch whatever surface you are working on. Tap the knockout plug out and pull the loose plug out from the inside of the garburator. You may need to reach in with a set of pliers if you cannot get it by hand.

DO NOT leave the metal plug behind inside the garbage disposal. You could cause significant damage to your disposal unit by operating it with a piece of metal stuck inside the housing.

Connect the dishwasher drainage line to the garbage disposal inlet and secure it with a gear clamp.

5. Wire The Garbage Disposal

It’s easiest to connect the electrical supply to the garburator before it’s mounted to the sink. You will have two options for electrical connections depending on the model you have purchased; hardwired or corded.

Hardwired Unit

The first step is to remove the cover plate on the underside of the garbage disposal. Most models of garbage disposers have the same set of colored wires as your home’s electrical system. Therefore, you need to connect the white-colored disposal wire with the white power supply wire, the black wire to black wire, and the green wire with the ground screw of your garbage disposal.

Tighten all connections, and run the wires through the bottom hole of the garbage disposal and replace the cover plate. If you are unsure at any point in wiring the garburator please consult the manufacturer’s instruction manual for added clarity. Always adhere to the electrical codes in your area.

Corded Unit

If you are fortunate enough to have an electrical outlet inside the kitchen sink cabinet, a factory-installed cord is simply plugged into the receptacle. Please wait until the installation is complete before plugging the unit. This will prevent accidentally switching the disposal on while finishing the installation.

6. Hang The Garbage Disposal

Now, it’s time to hang the disposer by sliding it into that mounting ring you previously installed. Holding the garburator in place, align the mounting tabs and start turning the lower ring clockwise until the unit is in position and supported by the mounting assembly.

Make sure the outlet of your disposer is facing the connection of the drain pipe.

6. Connecting The Plumbing

Start off by inserting the disposal discharge tube into the discharge coupler. Then slide the clamp over the discharge tube stopping in the groove on the rubber tailpipe coupler.

With the discharge tube inline with the plumbing drain trap, measure and cut the excess part off with a tubing cutter or hacksaw. Remove any burrs on the cut edge of the discharge tube. Now install this pipe to your disposer’s outlet and attach the drain line using the slip nuts. 

If your discharge tube doesn’t line up with your existing plumbing, you may need modify it to accommodate the new garbage disposal.

7. Tighten And Test

Now insert a wrench or a screwdriver into the lug that is present on the lower ring and start turning clockwise until the unit is locked into place.

Secure The Garbage Disposal

You can add a zip-tie or other fastener to the screw of the mounting ring and a tab from the lower ring to prevent the assembly from accidentally vibrating loose.

Now tighten all the drainage connections snug with the help of your pliers. It’s time to run the water in your sink and also power up the disposer and see if there are any leaks. Fill the sink bowl with water and drain it to test your connections. If there are any, then you need to tighten the fittings as needed.

Switch on the garbage disposal and run water through the unit to test its operation. You should notice the water drain from the sink much faster with the disposal running.

Clean up any more putty that has squeezed out around the drain flange and insert the sink baffle as a final touch. Done!

Operational Tips 

Here are some tips on how to get the most out of your new garbage disposal.

Things You Should Never Put Into Your Garburator

Your garburator is not a trash can. Not all liquids and food scraps are meant to go into it. To prevent any clogging or plumbing issues, you must understand which types of food are safe to go into your disposal.

Potato peels can create a starchy paste when ground, so avoid these if possible. The same goes for banana peels, they can create a stringy mess inside your disposal unit and plumbing.

Avoid coffee grounds and eggshells. These materials will pass harmlessly through the disposal but they have a tendency to settle out as sediment and collect inside your plumbing. Over time they will restrict the flow through the pipes or clog the plumbing entirely.

Make sure that you don’t allow any fats, oils, or grease to enter the garburator. These are not meant for a garbage disposal or your plumbing for that matter. You need to trash them properly.

Cleaning And Maintenance

Sink disposals require little to no maintenance but they do need to be thoroughly cleaned to prevent odours. Cleaning once a month is often all it takes.

Remove the baffle or cover and give it a good scrub with soapy water. Most food waste will cling to rubber or plastic surfaces so make sure all the edges are cleaned.

A couple of handfuls of baking soda and half a cup of vinegar can help clean the garburator chamber with its foaming action. Let it sit and bubble for a few minutes before rinsing with a generous amount of water.

If you don’t like the smell of vinegar or want a simpler way of cleaning your disposal, we recommend these:

You can freshen up your disposal regularly by grinding up ice cubes and a few slices of lemon or orange. If you don’t have fresh citrus fruits available these freshener tablets work too:

Conclusion

Installing a garbage disposal yourself is a pretty simple process. But always check your local municipal regulations before you start to ensure you’re allowed to have one.

With a little time and patience you too can have the convenience of simply scraping dishes off into the garburator before tossing them into the dishwasher. And your nose will appreciate less food waste stinking up your trash cans!

Happy Plumbing!

Trevor Woods is the founder of Plumb University® and he started in the plumbing and construction industry in 1997. Since then, his mission is to make plumbing repair and maintenance easy for everyone. And each year, he continues to help more people with their plumbing installation, care, and troubleshooting.