The Dishwasher Air Gap – An Ultimate Guide

Introduction

Ever noticed that small, cylindrical fixture next to your kitchen sink and wondered what it’s for? That’s a dishwasher air gap, a crucial component for maintaining a clean and efficient dishwasher. This guide will walk you through everything you need to know about dishwasher air gaps: what they are, how they work, if you need one, and how to install and maintain them.

What is a Dishwasher Air Gap?

A dishwasher air gap is a small yet essential plumbing device that prevents dirty water from backflowing into your dishwasher. It ensures that once the dirty water exits your dishwasher, it doesn’t find its way back, thereby keeping your dishes and dishwasher clean.

How It Works

It creates a physical gap of air between the dishwasher and the sink drain, ensuring no dirty water can siphon back into the dishwasher. It consists of two hoses: one connects to the dishwasher and the other to the kitchen sink drain or garbage disposal.

Why You Need a Dishwasher Air Gap

Preventing Backflow

The primary function of a dishwasher air gap is to prevent backflow. When water pressure changes, there’s a risk of dirty water being sucked back into the dishwasher. The air gap eliminates this risk by creating an unpressurized space.

Compliance with Plumbing Codes

In many states, including California, Washington, Minnesota, and Hawaii, installing an air gap is mandatory by law. Even if not required by local codes, an air gap is a good idea for ensuring your dishwasher operates hygienically.

Installing a Dishwasher Air Gap

Materials Needed:

• Dishwasher air gap fitting
• Screwdriver
• Hose clamps
• Drill (if a hole needs to be made in the countertop)

Steps to Install:

1. Locate or Drill Hole in Countertop: Find the pre-cut hole for the air gap on your counter. If there isn’t one, drill a 1-3/8″ hole close to the sink rim.
2. Disconnect the Dishwasher: Turn off the dishwasher’s power to ensure safety during installation.
3. Connect Air Gap to Dishwasher Drain Hose: Attach the dishwasher’s drain hose to the smaller leg of the air gap, securing it with a hose clamp.
4. Connect Air Gap to Sink Drain or Garbage Disposal: Cut and connect a length of 7/8″ tubing from the air gap to either the sink drain or the garbage disposal, securing it with a hose clamp.
5. Secure the Air Gap on the Counter: Insert the air gap through the hole from below, tighten it with a nut, and secure it in place.
6. Test for Leaks: Run the dishwasher on a fill cycle to check for any leaks.

Maintaining Your Gap

Regular maintenance ensures your dishwasher air gap functions properly. If you notice water spilling from it, there might be a clog. Here’s how to clean it:

Cleaning Steps:

1. Remove the Air Gap Cover: Twist off the cover to access the air gap.
2. Clear the Clog: Use a long-handled brush or blow through a paper towel tube to dislodge debris.
3. Check for Knockout Plug: If you have a new garbage disposal, ensure the knockout plug is removed.
4. Reassemble: Once cleaned, reassemble the gap and test your dishwasher.

Dishwasher Air Gap Alternatives

If you prefer not to use an air gap, there are other methods to prevent backflow:

High Loop Method

This involves routing the dishwasher’s drain hose to a high point under the sink before it goes down to the drain. It uses gravity to prevent dirty water from flowing back into the dishwasher.

Standpipe

A standpipe is a vertical pipe into which the dishwasher drains. It must be properly vented and above the sink’s flood level to prevent backflow.

Wrapping Up

Understanding and maintaining your dishwasher air gap is crucial for the efficient operation of your dishwasher. Whether you choose to install one or use an alternative method, ensuring proper drainage and backflow prevention will keep your dishes clean and your kitchen sanitary. If in doubt, consult a professional to get the best setup for your kitchen.

Call 1-Tom-Plumber 

Don’t hesitate to contact us here or call us at 1-Tom-Plumber (1-866-758-6237) if you need any plumbing, drain cleaning, water damage, or excavation service. 1-Tom-Plumber’s certified team of plumbers and drain technicians respond immediately to any emergency plumbing, drain cleaning, or water damage problem. We also handle the excavation of underground water lines and sewer main lines. Our immediate-response team is available every day and night of the year, even on holidays.