Whirlpool Dishwasher Leaking from Air Gap: Troubleshootin... | appliancefaults.com

Technical Background:

The air gap is designed to prevent backflow of contaminated water into the dishwasher. When the drain line is restricted, the dishwasher's drain pump forces water up the drain line. If the back pressure exceeds the air gap's capacity, water will exit through the air gap. The dishwasher's MCU (Main Control Unit) controls the drain pump motor via a relay, energizing the pump motor at 120V AC during the drain cycle.

Symptoms:

The homeowner observes water leaking from the air gap located near the kitchen sink, but not directly from the Whirlpool dishwasher itself. This typically occurs during the drain cycle.

Possible Causes:

Clogged drain line causing back pressure
Partially blocked air gap
Improper air gap system
High loop in drain line installed incorrectly
Drain hose connected to disposal incorrectly

Solution:

1

Disconnect power to the dishwasher at the breaker panel. Use a multimeter to verify 0V AC at the dishwasher's junction box.
2

Inspect the air gap for blockages. Remove the air gap cap and clean out any debris with a small brush or pick. Use a flashlight to inspect inside the air gap.
3

Disconnect the drain hose from the air gap. Check for clogs in the hose. Flush the hose with water to remove any obstructions. A garden hose can be useful.
4

Verify the drain hose has a proper high loop before connecting to the disposal or sink drain. The high loop should be at least 20 inches above the floor.
5

Inspect the drain connection at the disposal or sink drain. Ensure there are no kinks or restrictions. Check the disposal knock-out plug is removed if the dishwasher drain hose is connected to the disposal.
6

Reassemble the drain lines and air gap. Ensure all connections are tight. Use hose clamps where applicable.
7

Restore power to the dishwasher and run a short test cycle to verify the leak is resolved. Monitor the air gap closely during the drain cycle.

Safety Warning:

Disconnect power to the dishwasher at the breaker panel before performing any repairs. Lock Out / Tag Out (LOTO) procedures should be followed. Be aware of potentially exposed 120V AC wiring.

Prevention:

Periodically flush the dishwasher drain line with hot water and vinegar to prevent buildup of grease and debris. Clean the air gap every 6 months.

Expert Tip:

Some Whirlpool dishwashers have a service diagnostic mode that allows you to manually activate the drain pump. Refer to the service manual or tech sheet for the specific model to access this mode. This allows you to observe the drain cycle without running a full wash cycle.

Frequently Asked Questions

•How high should the high loop in the drain line be?

The high loop in the drain line should be at least 20 inches above the floor to prevent backflow.

•What is the proper way to connect the dishwasher drain hose to a garbage disposal?

The dishwasher drain hose should be connected to the designated inlet on the garbage disposal. Make sure the knock-out plug inside the disposal inlet has been removed before connecting the hose.

•What tools do I need to remove the dishwasher to inspect the drain line?

Typically, you will need a 1/4-inch nut driver, a Phillips head screwdriver, pliers, and possibly a small flathead screwdriver to disconnect the water and drain lines. Also, you'll need adjustable wrenches to disconnect the water lines.

Whirlpool Dishwasher Leaking from Air Gap: Troubleshooting & Solutions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How high should the high loop in the drain line be?

•What is the proper way to connect the dishwasher drain hose to a garbage disposal?

•What tools do I need to remove the dishwasher to inspect the drain line?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: