What is a Dishwasher Air Gap and Are They Necessary?

What is a Dishwasher Air Gap?

A dishwasher air gap is a device that helps protect your dishwasher from contaminated water.

Many dishwashers don’t have built-in backflow prevention. Backflow happens when dirty, contaminated water is mixed into the clean water supply. Why is this important? Backflow can lead to contamination inside your dishwasher and create an environment that can lead to foul odors and health issues. This is where dishwasher air gaps come in.

Dishwasher air gaps are installed on countertops with the tubing connections occuring underneath the kitchen sink.

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What does a dishwasher air gap do?

A dishwasher air gap prevents dirty sink drain water from funneling into your dishwasher, which can contaminate your dishes. In some areas, you are required to have some form of backflow prevention.

It will keep your dishwasher running optimally and your dishes in top-top shape.

Do dishwashers come with an air gap?

Surprisingly, many dishwashers do not have built-in backflow prevention or an air gap. However, some dishwashers have a drain hose looped upward and attached to the bottom of the countertop.

What to do if your dishwasher has no air gap

You must first understand the risks if your dishwasher has no air gap. Contaminated water from your kitchen sink or garbage disposal may flow back into your dishwasher without backflow prevention. There are a few alternative options for backflow prevention, including installing a high loop or standpipe setup on the underside of the countertop or installing a check valve in the drain line. Whatever solution you choose, we recommend hiring a professional to ensure that your dishwasher has backflow prevention installed. By prioritizing backflow prevention, you ensure your dishes’ and dishwasher’s safety and cleanliness.

Dishwasher Air Gap Alternatives

Two other ways to ensure backflow prevention do not require installing an air gap.

The first is the high loop method. This involves positioning the dishwasher’s drain hose in a “high loop” or elevated arc higher than the sink’s drainage line. This prevents backflow by utilizing gravity so the water cannot bypass. This method is easy to implement and compatible with most plumbing systems.

The second option is a standpipe setup. This involves connecting a vertical pipe to the sink’s drain line. The hose attaches near the top of the standpipe, preventing backflow from draining into the dishwasher.

No one is better than the other, so it is best to choose which method works best for you and your budget.

How much does it cost to install?

The cost can vary. Many resources can teach you how to install a dishwasher air gap yourself, but we recommend contacting a plumbing professional to have it properly installed.

How to install a dishwasher air gap

If you choose to install a dishwasher air gap, here are some basic instructions that can help:

1. Gather your supplies. These supplies may include the dishwasher air gap, a screwdriver, and hose clamps.
2. Choose your installation. Dishwasher air gaps must be installed on a countertop, so you must use an existing hole or drill a hole.
3. Turn Off Your Dishwasher. Disconnect your dishwasher from its power source during this process.
4. Connect the Drain Hose. Locate your dishwasher’s drain hose. This often flexible tubing can be found near the bottom or linked to the sink drain. You’ll need to connect this tube to the air gap using hose clamps to ensure the connection is tight and to prevent leaks.
5. Attach the air gap to the disposal source. The air gap will need a place to siphon water from the dishwasher, so connect it to the sink’s drain or garbage disposal. Use a hose clamp to connect the other end of the tubing to prevent leakage.
6. Install the air gap. If your air gap has a vanity cover, remove it before pushing the air gap fitting through the hole. You’ll do this from underneath the countertop.
7. Check installation. Once you’ve pulled the air gap through the hole in the countertop, twist it to ensure it’s secure. You can reattach the vanity cover at this step.
8. Test. Once you’ve finished your installation, you’ll want to test your handiwork. Reconnect your dishwasher to power and run a cycle. Check for any leaks during this cycle before resuming everyday use of your dishwasher.

Should water come out of the air gap?

Occasionally, air gaps linking water may mean you need to run the garbage disposal. When an air gap leaks, the tube could have a kink or blockage. You can quickly fix this by cleaning the air gap, checking the drain line below the sink, pulling off the air gap, and checking the opening for obstructions.

How to Clean a Dishwasher Air Gap

You can clean a dishwasher air gap in a few easy steps.

Step 1: Remove the vanity cover or cap.

Step 2: Clean the interior of the air gap thoroughly. For best results, use a long-handled bottle brush to effectively remove gunk or food particles from the tubing.

Step 3: Check for leaks. Once you’ve cleaned the dishwasher air gaps, check for any leakage from the tubing underneath the sink.

Step 4: Make it Part of Your Cleaning Schedule. Add regular maintenance and cleaning for your air gap to your kitchen cleaning routine. This will help prevent any backups in the future.

We hope this information is helpful to you and helps you eliminate backflow issues so that you can create a healthy, well-functioning dishwasher.