If you have a garbage disposal installed in your kitchen sink, it's typically not necessary to have a separate air gap for your dishwasher. The purpose of an air gap is to prevent wastewater from flowing back into the dishwasher, which can happen if there is a clog or a backup in the drain line. However, a properly installed and functioning garbage disposal can serve as an alternative method of preventing backflow.
The garbage disposal typically includes a built-in "anti-backflow" feature called a "disposal knockout plug" or "dishwasher plug." This plug, when removed, allows the dishwasher's drain hose to be connected directly to the garbage disposal. This configuration ensures that any wastewater from the dishwasher is directed into the disposal unit and eliminated with the rest of the kitchen waste.
It's important to follow the manufacturer's instructions and local plumbing codes when connecting the dishwasher drain hose to the garbage disposal. Additionally, regular maintenance and cleaning of both the dishwasher and garbage disposal are recommended to ensure their optimal performance.
If you have specific concerns or if local regulations require an air gap for your dishwasher, it's advisable to consult a plumber or a professional familiar with your local plumbing codes to ensure compliance and proper installation.