April 3, 2017

Have you ever run the dishwasher and come back to find water spouting all over your sink, countertop, or even the floor? Did the water come from the strange protrusion next to your faucet? Bet you always wondered what that thing did (before you found out it floods your kitchen). “That thing” is actually called an air gap, and it prevents wastewater from siphoning back into the dishwasher, which can occur when sinks become clogged and no air gap is present. Without an air gap, contaminated water could be sucked back into the dishwasher, dirtying your clean dishes and making you ill.



In a properly functioning air gap, the dishwasher hose attaches to an input on the air gap, and the water is expelled out the end. Gravity pulls it downward into the hose, which carries it to the garbage disposal. The gap where the water falls downward through the air instead of a hose functions to prevent siphoning, and thus prevent backup into the dishwasher. Over time, food can clog an air gap, preventing water from flowing. Alternatively, when a new garbage disposal is installed, the installer forgets to remove a knockout plug from the input to which the water line is attached. Either of these situations is quite easy to fix, and below we’ll show you how.


One of the most common reasons for an air gap clog is failure to remove the knockout plug from the input where the water line enters the garbage disposal. This blocks the water from entering and causing a backup. To solve this, simply detach the water line from the garbage disposal, insert a screwdriver into the input and tap it with a hammer to pop the knockout plug out. Before using the disposal, be sure to reach into the garbage disposal and take the knockout plug out.

For softer clogs, pop the cap off of the air gap, and place a cardboard tube from a roll of paper towels over the hole. Blow through the top with a good amount of force, and any material should come loose. If this doesn’t work, though, you can use either a long bottle brush or a wet/dry vacuum to remedy the issue. Using a bottle brush, simply extend it down the air gap (not the line from the dishwasher, but the line leading into the disposal) and twist it until the debris in the line comes loose. Or, with a wet/dry vac, place the hose over the air gap, turn it on, and wait forty seconds to a minute. By that point, anything in the air gap should be sucked out.

Ultimately, with a few simple steps, you can prevent contamination of your clean dishes from whatever evil microbes lurk in your sink, and that can’t be a bad thing. Always remember that if you have further questions, Baker Brothers Plumbing is here to help.

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