How to Install a Garbage Disposal with a Dishwasher

Generally, the installation of garbage disposal and dishwasher go hand in hand. For some reason, if your kitchen setting does not have both or you have no idea how to set it up, then fret not, we will walk you through the whole process. Just follow the steps mentioned below.

Tools and Materials Needed to Install a Garbage Disposal with a Dishwasher

• Screwdriver
• Hammer
• Hacksaw
• Needle-nose pliers
• Groove pliers
• Plumber’s Putty
• Metal Sink Cover
• Pipes

Steps to Install a Garbage Disposal with a Dishwasher

Step 1 – The first thing we will do is switch off the power supply from the circuit breaker. Now we will put a power cord on the garbage disposal. Generally, the garbage disposals do not come with a power cord attached to it and you have to buy it separately.

To install the power cord, locate the panel at the bottom section of the disposal. Open the panel and you will find the white wire, black wire, and green ground screw. You need to attach the white wire with white, black wire with black, and green wire to the green ground screw.

Now, install the clamp into the hole next to the panel, and pass the power cord through it. Close the clamp and the panel and tighten the screws with the help of a screwdriver.

Step 2 – Now we will install the garbage disposal drain flange. Take plumbers putty and roll it between your hand to form a rope that is ½ inches in diameter and is long enough to wrap around the drain flange.

Clean the sink around the drain opening and insert the drain flange into the sink. Align the flange in the center and press the flange with your hands or with some heavy object until you see plumbers putting coming out from around the edges.

Remove the excess putty with the rag.

Step 3 – Now we need to get underneath the garbage disposal and install the mounting ring. The mounting ring is a progression of parts that includes a fiber gasket, the backup flange, the mounting ring, and the snap ring.

Attach the fiber gasket, backup flange, and mounting ring to the end of the drain flange from underneath the sink. Insert the snap ring into the groove of the fitting to secure the mounting ring.

Now attach the mounting ring with the backup flange and tighten the screws until the extension is tightly fit beneath the sink

Step 4 – Now, for the other side of the sink, take plastic or metal sink cover, put plumbers’ putty around it, and insert it into the drain hole. Apply some pressure, but not too much if you are using a plastic sink cover as the pressure could break the cover.

This sink cover also has a similar progression of parts which includes a cardboard gasket, rubber gasket, and the mounting ring. Insert them one by one and tighten them with screws.

Step 5 – Before installing the garbage disposal we need to install a diverter into the main water line to connect it with the dishwasher. For that, you need to purchase a 3/8 to 3/8 pipe threads and a pipe.

Loosen the clamp from the end of the main water line with the help of pliers and let the water drain out from it. Now attach the diverter and the new pipe with it and tighten the clamps.

Step 6 – Now we will attach the pipe that comes with the garbage disposal. There will be a hole in the garbage disposal for attaching the pipe.

To do that, take the drain gasket and place it on one end, take the metal ring and pass it through the pipe towards the hole, and bolt the ring into the garbage disposal with the help of a screwdriver.

Step 7 – Before mounting the garbage disposal, we will remove the metal plug where the dishwasher drain hose gets connected. You can find a tube being blocked by a metal plug on the upper side of the garbage disposal.

To knock out the metal plug, take a screwdriver and a hammer and punch the plug. Be careful while using the hammer. Once the metal plug gets knocked out, use needle-nose pliers to remove it.

Step 8 – Now we will mount the garbage disposal. Get underneath the sink, raise the garbage disposal, insert the mounting collar into the mounting ring loops, and tighten it with the help of an allen wrench or hex key.  

We have finished installing our garbage disposal, now we need to find out how to plumb a kitchen sink with disposal and dishwasher.

How to plumb a kitchen sink with a disposal and dishwasher

To plumb a kitchen sink with garbage disposal and dishwasher we inserted a diverter in the main water line in step 5. So now we will connect the diverter with the dishwasher and complete the installation of the remaining waste pipe.

1. Extend the pipe from the diverter and connect the pipe with the dishwasher and tighten the clamps with pliers. Make sure it is tight enough to avoid any leakage.

• Now, connect the dishwasher drain hose with the garbage disposal. Insert the drain hose into the tube on the upper side of the garbage disposal, put the clamp around the connection point, and tighten the clamp with a screwdriver.

• Now to complete the installation of the waste pipes, measure the length of the distance between the main drain hole and the garbage disposal, and cut the pipe with hacksaw accordingly. Tighten the pipe with the help of pliers.

Final Checks

Run a few final checks just to see everything is working properly. Turn on the water, let it pass through the garbage disposal, and look for any leaks in garbage disposal or pipes.