Tools and Materials
How to Install a Dishwasher Drain Hose
To install a dishwasher drain hose, you must secure its connection from two sides: the dishwasher and the sink. Follow the instructions below detailing how you can connect the dishwasher drain hose to the sink and the dishwasher.
Before you replace the hose, shut the water connection to the dishwasher. If you have a garbage disposal installed in the sink, make sure you turn it off as well. If you are installing a hose for the first time, you can skip the next three steps and continue from Step 4.
Now, bend over to reach the hose connection on the side of the sink. Place a bucket below this hose connection to catch any water that might drain off from the hose.
Your dishwasher hose may either be directly connected to the drain below the sink or to a garbage disposal. In both cases, you must unscrew the hose clamp using a screwdriver.
Unscrew the Hose from Air Gap
Some of the dishwasher to the drain connections go via an air gap. The dishwasher air gap makes an easy passage for gases to escape. It also ensures that dirty water does not flow back into the dishwasher. If your old hose pipe has this connection, pull the hose to disconnect it from both the inlet and outlet of the air gap. If your old hose pipe has this connection, pull the hose to disconnect it from both the inlet and outlet of the air gap.You might want to install an air gap because of its benefits or because your local code requires it. To do so, you must first consult a professional to make a cavity in your countertop to fit the air gap.
In some states, installing air gaps with dishwashers is mandatory. Consult your local code before installing a dishwasher.
You may connect a hose directly to the drain or a garbage disposal. Installing a garbage disposal allows you to drain some food scraps directly into the sink.
Take your new dishwasher hose and push it into the drain connector or garbage disposal below the sink. Slip a hose clamp onto the connection made and tighten it with a screwdriver.
Disposing of fibrous foods, meat, hard bones, pasta, oil or animal fat can choke the garbage disposal.
It is necessary to prevent dirty water from backflowing from the sink. This can be achieved by installing an air gap or providing a high loop. An air gap is a small fitting that is mounted over the countertop. High loop refers to elevating the drain pipe near the sink.
Air Gap Connection
An air gap has two openings for pipe connections. The bigger opening is for the water outlet and the smaller one is for the water inlet. Take the remaining end of the hose that you connected to the sink. Now push it into the outlet opening of the air gap.
Take the air gap with one hose connected to the outlet. Place it in the countertop hole and bring the air gap body outside. Secure the bottom retainer nut below the counter.
On the air gap body above the countertop, place the counter gasket. Secure the top retainer nut and top cover nut over the gasket. Now place the decorative cap over it.
High Loop Connection
Hold the hose connected to the sink and bend it slightly to form an inverted U-shape. Adjust it so that the loop is at least at a height of 32 inches from the floor.
Use a plumber’s tape to secure it in this position. Stick the hose to the insides of your cabinet. You can also use a plumber’s hanging tape or zip tie for this task.
If you are wondering how to connect dishwasher drain hose to disposal, start by locating its drain pipe.
Connection through an Air Gap
Bend again to access the air gap body below the countertop. Take the dishwasher drain pipe and push it into the air gap inlet or the smaller opening. Secure this connection with a hose clamp and screwdriver.
Connection through a High Loop
If you are connecting the hose without an air gap, push the hose into the dishwasher’s drain pipe. Tighten this connection using a hose clamp and a screwdriver.
Turn on the water flow and start the dishwasher. Look for any water leakage across the hose connection. If there are no leaks, your dishwasher hose connection is complete. If you find any leakage, repeat the above steps to connect the hose correctly.