Let precision in the kitchen protect you from water contamination. Follow these simple steps for installing a dishwasher air gap.
What Is a Dishwasher Air Gap?
An air gap knows where the backflow goes
Get quotes from appliance repair pros near you
No obligation · 100% free
Get quotes from appliance repair pros near you
No obligation · 100% free
Need Help With a Project? Connect With a Pro
A dishwasher air gap prevents contaminated water from flowing back into your dishwasher, keeping your dishes clean and your home safe.
Some states require dishwasher air gaps by code, and alternatives like high loops or standpipes are less effective at preventing backflow.
Water leaking from your dishwasher air gap indicates a clog in the tubing that needs immediate attention to restore proper drainage.
Hiring a local dishwasher repair professional provides reliable help clearing clogs and replacing air gaps, keeping your dishwasher running smoothly.
Get quotes from up to 3 pros!
Enter a zip below and get matched to top-rated pros near you.
Have you ever wondered what that small cylinder is on your kitchen sink? That little bit is your dishwasher's air gap. To the naked eye, it doesn't seem like much. But when it comes to plumbing and the cleanliness of your dishwasher, the air gap is an essential, and sometimes legally required, part of the system.
So, what is a dishwasher air gap, and do you need one?
What Is a Dishwasher Air Gap?
A dishwasher air gap is a small cylindrical fitting that connects the kitchen sink to the dishwasher. It sits elevated on the sink above the dishwasher to prevent dirty dishwater from flowing back into the appliance and all over clean dishes during a cycle. It ensures your dishes stay clean, and the wastewater funnels into the kitchen sink plumbing.
How Does a Dishwasher Air Gap Work?
The dishwasher air gap works using simple physics. The elevated air gap creates two channels in the hose: the dishwasher to the air gap and the air gap to the disposal or sink. When a dishwasher drains, it pumps the dirty water through the tube, reaching the peak, then falling down the other side and draining out.
The cylinder above the sink has a literal gap with a notched hole. This air gap prevents contaminated water from flowing backward. If the air gap is clogged, the contaminated water will simply flow into the sink, not back into the dishwasher.
Where Is the Dishwasher Air Gap?
Photo: chuckcollier/ istock/ Getty Images
The dishwasher air gap is installed on the kitchen sink, most often next to the faucet handles. It’s cylindrical in shape and often chrome or stainless steel. You may have seen dishwasher air gaps before and not even noticed them.
Is My Dishwasher Air Gap Working?
If water starts to come out of your dishwasher's air gap during a cycle, it’s an indication that something is wrong. Water from your dishwasher's air gap is likely a sign of a clog in the tubing. If you can’t clear the gap on your own, it’s time to reach out to a professional who fixes dishwashers. Contact a dishwasher repair service near you to clear the line of clogs and bring your air gap back into shape. Having a pro replace a dishwasher air gap costs between $80 and $150. But, if your dishwasher isn’t cleaning, it could indicate additional issues.
Do I Need a Dishwasher Air Gap?
Some, but not all, states require dishwashers to have an air gap to be up to code. If you live in one of these states and install a dishwasher without an air gap, it could cause issues if you try to sell the home or repair the washer. Plus, you could be sending dirty water back into a clean dishwasher.
Even if your state doesn’t require a dishwasher air gap, you’ll need it, or an alternative, to prevent wastewater from flowing back into your dishwasher. A plumber may recommend a high loop or a standpipe instead, but neither is as effective as an air gap at preventing backflow.
Additionally, some dishwashers come with built-in air gaps, but many of these built-in air gaps don’t satisfy state plumbing codes. When installing a new dishwasher, it’s best to consult with an experienced plumber for best practices.
Appliance repairs reviews from real Angi homeowners in Columbus, OH
4.3★ avg. • 49 total reviews
- Julio V.
Positive experience. As previously stated, the replacement/repair could not be completed (no fault of the plumbing tech) b/c misinformation was rec?d by property management maintenance. Thanks to the plumbing tech for your efforts. Appreciate you!
The Waterworks - Brent C.
Carpet repair done well. Scheduling was easy. Showed up on time.
BR Flooring Installation - Mike Z.
As usual with ECO, tech Jordan was outstanding, very professional, very knowledgeable, and very thorough with repairs made to tankless water heaters. Very highly recommend ECO!!!
Eco Plumbers, Electricians, and HVAC Technicians - Austin Y.
I would recommend this company to anyone! He showed up on time, was friendly, completed a very difficult repair on our dryer vent cover, was responsive, and pricing was extremely fair and competitive. I would have him back to do any of our repairs or cleanings without hesitation!
U.S.A. Dryer Vent, LLC - Micki B.
Everything from initial contact to completion was absolutely top notch. We contacted the business during off hours to leave a message, and the owner still reached out to feel out the issue within minutes. We were scheduled and repaired within 48 hours. I cannot say enough about the...
Supreme brick & chimney - Donald L.
Ace Fireplace Services came to the rescue for my chimney repair. They were quick to pinpoint the issue and worked their magic to fix it. My chimney is now in excellent shape, and I'm a satisfied customer.
Ace Fireplace Services - Lisa S.
On Sunday 2/26 I requested quotes via Angi from 4 refrigerator repair businesses. Northwest Appliance responded to me Monday morning (2/27) and my refrigerator was repaired by noon the same day. Great communication, they did everything they said they would. The technician had the parts on...
- Aaron M.
Excellent! We were very satisfied with the service provided and the entire experience from start to finish. Very friendly and professional staff. I was able to instantly get in contact with them for a quote and the response time and overall communication remained quick and easy throughout the...
Prime Cleaning Service - Michael H.
Description says they handle window repair including rotten hardwood - they called me back right away but didnâ t leave a voicemail. I followed up 3 days later and they said they donâ t do that kind of work.
Window-Gurus - Evan O.
I needed reliable, affordable help the day of with moving a couple of appliances and misc items. It was a relief to hear back from Tanzillo almost instantly that morning so I could stop looking and move on to plan and prepare. Every part of the move was friendly and professional. Next time I...
Tanzillo Concrete & Landscape
The homeowners guide to appliance repairs
From average costs to expert advice, get all the answers you need to get your job done.
You can usually unclog your dishwasher by cleaning the filter and using a DIY solution to clear the drain hose. Learn more with this step-by-step guide.
Understanding the different parts of a dishwasher can help you troubleshoot any issues and know when to call in the professionals.
Looking to extend the life and increase the efficiency of your dishwasher? Learn how to clean a dishwasher drain to enjoy a clean, dry load every time.
Dishwasher not draining properly? Discover what’s going on with your dishwasher drain and how to fix problems like clogged drain lines and garbage disposals.
When your dishwasher is not getting water, don’t just give up and wash dishes by hand. Trust our tips to troubleshoot a dishwasher that won’t fill with water.