Is your dishwasher not draining correctly? It is very tricky to pinpoint what is wrong with it because there are a lot of possible reasons, and some do not even involve the gadget itself. Sometimes, it will include problems with the gadget’s plumbing that need to be addressed before you replace or repair the unit.

Take note; you need to be aware that it’s normal for dishwashers to retain some water at the bottom of the tub after it completed a cycle. If your machine has a small pool, you need to check the owner’s manual to see if having a small amount of water in the tub is normal, if you can’t find the information in the manual, you can always call the manufacturer if you are having an issue with your dishwasher not draining.

Causes of the problem that are plumbing-related

It might be a surprise to anyone, but usually, drainage problems when it comes to dishwashers are actually because of the drain parts outside the appliance. To repair these, you need supplies and tools like assorted screwdrivers and wrenches, as well as air gap fittings if necessary. Not all the steps will be mentioned here needs to be completed. Continue reading to know the reason for the drainage problem of the dishwasher. If the issue is not discussed here, you can proceed to the gadget itself.

Check garbage disposal

Usually, the hose of the dishwasher drain is connected to the garbage disposal unit. When there is built up of food inside the garbage disposal, or when it is clogged, there is less space for the water to go. Run the disposal unit thoroughly with a lot of flowing water to clear the hose out. This method will fix the drainage problem of the appliance.

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Clean its air gap

An air gap is the small cylinder on the back of the kitchen sink. By cleaning it and preventing air vacuums, it is made to avoid any drain water from going back to the dishwasher. If the water comes out of the air gap, when you run the dishwasher, there will be a blockage between the garbage disposal unit and the air gap.

To clear this blockage, remove the cap and clean the inside of the air gap. The next thing you need to do is disconnect the hose that runs from the nipple of the air gap to the disposal unit or sink drain, and you need to make sure that it’s not clogged.

Check its high-loop

If your unit does not have an air gap, the drain hose may be looped up, and it is attached to the unit’s bottom of the countertop near the kitchen sink. Although it is not code-compliant in most houses, the high-loop serves the same purpose as the unit’s air gap. It prevents drain water from going back to the dishwasher.

If the hose is loose, it is no longer looped up higher the dishwasher’s level. It can prevent water from draining out properly from the appliance. Putting the hose back to its high-loop position will fix it. You can also install the right air gap.

Note to remember: If you have just installed a new disposal unit, you need to make sure that the plug inside the appliance’s drain hose nipple has been removed. Modern disposals have a small plastic disc that is covering the drain opening. It needs to be punched out using a screwdriver and a hammer. The disk can fall into the garbage disposal’s grinding chamber, where you can get it out.

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Dishwasher-related cause

If there are no plumbing-related problems, the drainage issues may originate with several possible components on the dishwasher itself. The supplies and tools that you need are sponge and bucket, screwdrivers and drain hose replacement if required.

Check the dishwasher’s drain screen

You need to check the unit’s drain’s screen which is at the bottom of the tub and make sure that nothing is obstructing it. Glass, clear plastic lids, labels, as well as bits of plastic can obstruct the drain, and it can be very difficult to spot unless you check it carefully.

Clean the filter

Dishwashers use different filter designs. Some have removable filters found below the screen, some have a simple screen, and some require you to remove the bottom spray arm for cleaning. Check the user’s manual for any instructions on how to clean your unit.