How to Install a Dishwasher Drain Hose

Dishwashers are complex pieces of machinery, and any misstep in their setup could result in a variety of problems including flooding, unclean dishes and unusually noisy wash cycles. The dishwasher drain hose is an essential piece of the puzzle, but it must be installed correctly to expel water and perform its job effectively. If your sink is equipped with a garbage disposal, connect the hose to the dishwasher discharge inlet on the disposal housing. If you’ve never had a dishwasher connected to this port in the past, you’ll probably have to remove the knockout plug from the port so that water can flow into the disposal housing. If you don’t have a garbage disposal, you’ll connect the dishwasher drain hose directly to the discharge port on the drain assembly. Homeowners may be able to install a dishwasher drain hose on their own, but shouldn't hesitate to call a plumbing professional for assistance.

Replacing the hose

No matter if you’re connecting the dishwasher hose to the garbage disposal or the drain assembly, for this project you’ll need pliers, a bowl, a nut driver and a stainless-steel hose clamp. First, you'll use the pliers to disconnect the current hose from the T-fitting underneath your kitchen sink. Drain water from the old hose into a shallow bowl, and use the nut driver to remove the old hose from the dishwasher. Secure the new hose to the discharge port with a stainless-steel hose clamp. The hose should be run as high as possible in your cabinet, forming an arcing loop, which you can affix with clamps. Once you've connected the hose to the T-fitting on the sink's drainpipe, run the dishwasher a couple of times with hot water to flush out the hose. There should be no dishes in the appliance during these initial cleanings.

Things to consider

While the dishwasher drain hose installation process may seem straightforward, there are some common mistakes associated with this project. If your kitchen sink does not have a garbage disposal, you’ll need to connect your dishwasher drain directly to the discharge port on the sink’s drain assembly. It’s important to ensure that the section of vertical pipe with a port designed to connect to the dishwasher drain hose, is connected to the sink side of the P-trap, not the sewer side. The water that sits inside the P-trap acts as a water barrier to prevent sewer gases from entering the house. Double check to verify that the dishwasher is draining into the P-trap on the sink side, not the sewer side, otherwise sewer gases will be able to make their way into your house.

Hooking up a dishwasher drain hose appropriately is critical to the appliance's continued performance. Don't hesitate to call a plumbing expert for assistance with dishwasher drain hose installation. Call a Roto-Rooter plumbing professional to set up your dishwasher drain hose and address and other plumbing issues you may have.

How to Install a Dishwasher Drain Hose