How To Remove The Knockout Plug From A Garbage Disposal
Like I mentioned before, all garbage disposal models come with a dishwasher inlet. This inlet is capped off by a knockout plug that is made of plastic. If you are going to connect a dishwasher to it, you have to first remove this plug. Removing this is easy
You should remove this knockout plug before mounting the garbage disposal to the sink. Once the garbage disposal is installed, it is difficult to remove this plug, especially if there isnt much space under the kitchen sink.
Sometimes people forget to remove the knockout plug before hooking up the dishwasher with the garbage disposal. As a result, the dishwasher will not drain, and the water will back up, flooding the kitchen. So it is important that you remove this plug correctly before connecting to a dishwasher.
S To Plug A Garbage Disposal Dishwasher Drain
Step 1 After removing the dishwasher drain hose, place a bucket near the garbage disposal dishwasher drain hole and let the remaining water drain out in the bucket.
Step 2 In order to plug a garbage disposal dishwasher drain hole, you will need a rubber cap first which is easily available at any hardware store and it costs around $1. The rubber caps are available in different sizes and the sizes vary from 3/4 to 1/2 . Just measure the size of the drain hole and get the rubber cap accordingly.
Step 3 Now all you have to do is take one of the rubber caps and stick it in the drain hole. Press it with your thumb and push it inside the drain hole to secure the opening. If you are worried that it has not fit properly then you can hit it a little bit with the help of a hammer.
Be careful not to push it very hard inside the garbage disposal as it will get difficult to remove it when you decide to install the dishwasher again.
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Wrong Side Of The Trap
The first problem is the dishwasher drain is connected to the sewer side of the trap. Water always sits in the bottom of the P-trap, and this prevents sewer gases from coming into the house. The dishwasher drain must be connected before the P-trap, not after it, which is what was done here. With this improper installation, sewer gases have the potential to come back into the dishwasher. The diagram below right shows a proper installation.
The diagram below right shows a proper installation.
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Do I Need To Cap A Waste Pipe
While renovating the kitchen interior it is best to cap off your plumbing before starting the operations. It is a good idea to seal the drain pipes for a while to prevent damage. If you have a leaky faucet, you will need to replace it with a new one. You can do this at home, or you can hire a professional plumber to do it for you.
The Dishwasher Will Not Drain

The dishwasher does not necessarily have a mechanical malfunction if it does not drain properly.
1. Inside the dishwasher at the bottom of the unit there is what looks like an upside-down cup. This is the float or pressure switch. Gently attempt to move it it should move up and down freely. If any large food particles, glass, plastic, etc. have become lodged under this switch, remove them so the unit can function properly.
2. If the float switch is functioning properly, then there may be a clog in the air gap. This is the hose that runs under the sink from the dishwasher to the cap on top of the sink. There may be an obstruction in the line or in the air gap itself. Remove the cap on the sink that exposes the air gap. If you see an obstruction , remove them. If no obstruction is visible, the top of the air gap should pop off or unscrew. Remove it to find out if you can see any other obstruction. If still no obstruction is visible, invert a plastic cup over the air gap opening then advance the dishwasher timer to the drain cycle to start pumping water through the line. If the obstruction is in the line, it should be pressurized out of the air gap opening. Be sure to keep your hand on the cup to prevent the water pressure from pushing it out of place. If the water runs through the air gap, shut off the dishwasher and reassemble the air gap.
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Capping Off The Drain With A Rubber Plug
Here is how to cap off the drain connection with teh above conical rubber plug
Here is the step by step process for capping off the dishwasher drain hole
Know When To Ask For Help
If the holidays have left your dishwasher and garbage disposal on life support and nothing you tried has worked, then now is the time to call Kotz and schedule an appointment. You should also consider scheduling annual plumbing maintenance as a preventive measure. Be sure to like and follow us on and for more great information like this.
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How To Remove The Knockout Plug
Another common issue with the dishwasher and garbage disposal is a dishwasher that is not hooked up properly, and has drainage problems. In this instance, you likely just recently installed a new dishwasher and a small detail was overlooked.
Your dishwasher needs to be hooked up to the garbage disposal in order to drain successfully. To do this, you should remove the knockout plug from inside your garbage disposal and install the dishwasher drainage tube.
In order to remove the knockout plug, you need a hammer and a screwdriver. Locate the plug by poking into the drainage hole on your garbage disposal. If it inserts easily, the drainage plug has already been removed and the drainage problems are not caused by the knockout plug.
However, if the screwdriver hits something solid, this is the knockout plug. Use the hammer to lightly tap the back of the screwdriver around the perimeter of the plug until it falls into the disposal unit. Use your hand or pliers to reach down through the sink opening to retrieve and remove the plug.
With the knockout plug detached, you can tightly affix the drainage tubing for the dishwasher and successfully thwart your drainage issues.
If You Are Unsure Why Your Dishwasher Isnt Draining
The dishwater isnt draining malfunction is a frustrating one, but dont allow it to consume you. Take action!
Schedule maintenance or checkup with a qualified professional today!
About the Author: Brett Bidwell, Mr. Rooter Plumbing of Austin
Brett has been a trusted Mr. Rooter owner of Mr. Rooter Plumbing of Austin since 2012. With over 8 years to back him, Brett has experience with a wide range of plumbing related solutions and systems. He and his team specialize in emergency plumbing, drain cleaning, and more.
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How To Cap Off The Inlet With A Dishwasher Connector Kit And A Copper Cap
Now that the dishwasher is installed, its time to cap off the inlet. This can be done with a dishwasher connector kit and a copper cap. The kit includes a clamp, gasket, and screws to attach the dishwasher hose to the garbage disposal. First, remove the old disposer plug from the sink and discard it.
Next, connect the dishwasher hose to the garbage disposal using the clamp from the kit. Make sure that the gasket is in place and tighten the screws. Then, screw on the copper cap over the end of the hose. This will keep debris from getting into the dishwasher inlet and clogging up your drain.
Now that the dishwasher is installed and the inlet is capped off, you can enjoy clean dishes without worrying about a clogged drain.
What About The Circuit
Both the dishwasher and the garbage disposal use electricity to run. Sometimes they will be set up on the same electrical circuit, and sometimes they will not. If they are on the same circuit, using them at the same time could cause your breaker to flip. Thats only if they are overloading the circuit by demanding more electricity than it has the capacity for.
Still, this is an installation and an electrical problem, not an inherent problem of running the two appliances at the same time. Your plumber can make adjustments so that the two run on different circuits. Or, you may need an electrician to resolve an underlying problem with the circuit or how your home is wired.
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Substances Required To Attach The Dishwasher Drain Hose To A Water Disposal
Twister, hammer, knife, drain hose, hose clamp, screwdriver, air gap connection, dishwasher, and waste disposal are required to fix the dishwasher drain hose to the garbage disposal. Now, we will discuss the steps to fix the dishwasher drain hose to the waste disposal. It is not a difficult job to connect with the garbage disposal. It does not need to require any electrical tool or energy. It is very easy, just a few things that you require to set in mind and you can do anything.
Step1: You need to remove waste disposal from the electrical circuit. Switch off the disposal unit from the mainboard if it is directly attached to the electrical socket. It is necessary to turn off any electrical connections because you do not want to get an electric shock.
Step2: There is a drain pipe part on the upper side of the waste they will collect the hose from the dishwasher. With the help of the screwdriver, you have to remove the plug. Eliminate all the metal plugs with the use of needle-nose pliers.
Step 3: And then attach thedishwasherdrainhose with the waste disposal and, with the help of the screwdriver, tight the clamp. Then with the knife, cut down the dishwasher drain hose, which is large to hit one side of the air gap, and fix this side using a hose clamp. Ensure that there is no twist on the hose when making the connections because it will limit the drain water and probably cause the blockage with the help of a wrench to tighten the clamp in the end.
How Do You Cap Off A Dishwasher Drain

The dishwasher drain on a garbage disposal can be capped off using a simple conical rubber plug that is 3/4 inches wide on its wider side. Simply push the rubber plug into the drain hole to cap it. You can also gently tap it with a hammer to make it tighter.
Is there a drain plug on a dishwasher?
What can cause a dishwasher to not drain? The most common reason a new dishwasher will not drain: There is a plastic knockout plug located in the disposal drain line that needs to be removed.
What is a knockout plug?
A knock out plug is a hole that has a cover over it. You will usually need to use a screw driver and a hammer to knock out the cover. Check out this picture. Once you knock out the plug, be sure to remove the plug because it may clog the drain if you leave it in there.
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Can A Dishwasher Drain Hose Be Too Long
Its possible. If your dishwasher drain hose is too long, it may not be able to properly connect to your garbage disposal. In this case, youll need to shorten the hose or use a different type of connection.
If your dishwasher drain hose is too short, it may not be able to reach the bottom of your sink. In this case, you can extend the hose using an extension kit or a PVC pipe.
Once you have the correct length of dishwasher drain hose, its time to cap off the end. This is necessary to prevent food and other debris from entering your garbage disposal.
Can You Use Your Dishwasher With A Broken Garbage Disposal
Come on now, admit it. Oh, go ahead, its just between the two of us. You used and ABUSED your garbage disposal and dishwasher during the holidays, didnt you? Grease and turkey bones in the disposal and lots of dirty plates with food still on them in the dishwasher. It doesnt make you a bad homeowner it just happens during the hectic family gatherings and huge holiday feasts.
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How To Remove A Dishwasher Hgtv
The nipple is on the side, but to hook a dishwasher you need to punch out the plate. The easiest way to cap off a disposalâs. However, there isnât a lot of information available about it on the. 24.how to cap off the dishwasher drain on garbage disposal capping off the inlet with a dishwasher connector kit and a copper cap.
image credit : dishwasherhelps.blogspot.com
Garbage Disposal Dishwasher Drain Plug Removal 29.when installing trash disposal, its common to practice neglecting the knockout plug on the side. 2.the trash disposal in most kitchens is connected to the dishwashers drain pipe.when you remove the dishwasher, however, you will be left with a gaping hole in the top of. Garbage Disposal Dishwasher Drain Plug Removal.
image credit : howotrmevo.blogspot.com
Garbage Disposal Dishwasher Drain Plug Removal 8.match the color of the wires and connect them right. 3.a garbage disposal dishwasher drain is rather simple to plug, and the process takes only a couple of minutes. Garbage Disposal Dishwasher Drain Plug Removal.
image credit : dishwasherhelps.blogspot.com
Garbage Disposal Dishwasher Drain Plug Removal Place the plunger adv lewat the drain and add water to the sink. 10.make sure the drain plug on the garbage disposal is removed. Garbage Disposal Dishwasher Drain Plug Removal.
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Soak The Standing Water And Check For Blockage
The first step is to remove as much water from the dishwasher as possible. Open the dishwasher door and start to soak the water with a sponge or towel. If there is a lot of water, use a cup or bowl, and empty it out.
Next, check the dishwasher drain for any blockage. See if food debris, grease, or other debris is causing a clog. If you find anything, remove it so the water can flow freely.
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How To Prevent This Issue
As mentioned previously, preventative measures are a great way to keep your dishwasher water from backing up into the garbage disposal. Small actions can make a big difference in the future. By keeping a few in mind, you can take charge of the drainage system in your kitchen.
Three of the preventative measure that you can use for your kitchen include:
- Avoiding the placement of certain items in your sink
- Rinsing everything, from the dishes to the disposal
- Checking for any obstructions that might be inside the system
These are some of the simplest ways to prevent blockage from happening again.
Read on to learn more about these preventative measures. Keep these in mind when you clear your dishes, and you should be able to keep everything in working order for as long as you can.
How Do You Unplug A Garbage Disposals Dishwasher Drain Plug
Gently hit the screwdriver against the plug with the hammer to help it pop out further. Then, with your hand on top of the plug.
Use the bottom of the screwdriver to move it around, creating momentum that will help you take it out more quickly.
With your finger, pull the plug deeper into the socket while slowly rotating it around until you obtain steam.
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Can You Shorten A Dishwasher Drain Hose
The answer is yes, but its not recommended. If you shorten the dishwasher drain hose, it could cause problems with your dishwashers drainage system. Additionally, it could also void your dishwashers warranty.
If youre having trouble connecting your dishwasher drain hose to your sink or garbage disposal, its best to consult a professional. They will be able to help you properly connect the hose and ensure that your dishwasher is draining correctly.
Inspect The Dishwasher Drain Hose

The drain hose is the black or white rubber hose that connects the dishwasher to the sink drain. If this hose is damaged, kinked, or not properly connected, it can cause your dishwasher not to drain properly.
First, check to see if the drain hose is kinked. If it is, straighten it out so the water can flow through more easily.
Next, check the connection between the dishwasher and the drain hose. Make sure that it is tight and not leaking. You may need to replace the drain hose if it is loose or damaged.
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