How to Install a Dishwasher: Step-by-Step Guide

As we mentioned on Monday, before flying out yesterday we finally replaced our bisque-colored dishwasher. The new stainless-steel model is a real crowd-pleaser (we like it, but Clara absolutely loves it). Here’s how the install went.

We had been telling ourselves we’d wait until the new floors were in so we wouldn’t accidentally trap the dishwasher behind new cork boards, but that was just an excuse. We could slide it on a few cork planks to match the future floor height, and the new dishwasher box had already spent too long in the office where it threatened to become a permanent side table.

Neither of us had installed a dishwasher before, and the idea of plumbing, electricity, and a tight space felt a little intimidating—especially since the old dishwasher cost $380. After watching a few YouTube tutorials we felt more confident, so when Clara went down for a nap we gave ourselves a pep talk and got to work.

First, we shut off the dishwasher’s hot water supply and cut the power. That step alone took a while because our breaker boxes weren’t labeled correctly, so we spent about 15 minutes testing breakers and coordinating trips to the basement to avoid any electrical mishaps.

With water and power off, I removed the access panel along the base of the old dishwasher. Behind the panel was the usual messy setup from years of DIY projects. Using a wrench I disconnected the water supply, keeping a rag handy for the inevitable drips—working in that cramped space took longer than I expected.

I hadn’t detached the drain hose from the disposal under the sink at that point because I’d already loosened it under the dishwasher to make room for tools. I tried to undo as little as possible in case we needed to back out.

Next came the electrical. The dishwasher wiring was contained in a small metal box that I removed with a screwdriver. I unscrewed the wire nuts and disconnected the old unit without incident.

To remove the old dishwasher, I lowered its adjustable feet so it wouldn’t press against the countertop, and then removed the screws securing it. Ours was fastened to the cabinets on either side rather than the underside of the counter, so I popped off a small plastic plug and unscrewed the brackets. A bit of shimmying and it slid out—on a piece of cardboard to protect the floor and make sliding easier.

With the cavity open, I prepared for the new floor by tucking rough-cut cork pieces into the space so the new dishwasher would sit at the same height as the future floor. That way it won’t be trapped behind floorboards later and will be easier to remove for service if needed.

Bringing the new energy-efficient dishwasher into the kitchen, I read the installation directions and realized I needed to reuse a 90-degree elbow from the old unit to route the water supply properly. It’s odd that this fitting didn’t come in the box, but at least I didn’t have to run to the store—yet.

Working with the dishwasher pulled out made everything easier, including lighting for photos. After attaching the elbow, the water supply line was long enough to connect while the appliance was still out, which made wrenching much more manageable.

Then I swapped the drain hose: I disconnected the old hose from the disposal and attached the new one. Although I could have left the old hose on the disposal and connected it to the new dishwasher, I preferred to have any potential leak visible under the sink rather than hidden behind the appliance.

On the electrical side I discovered I was missing a strain relief, so I did make one unplanned trip to the hardware store to pick one up. The strain relief holds the wire so the connections don’t get pulled. Once installed, I reconnected the wires with wire nuts, replaced the cover, and went to the basement to switch the breaker back on.

Power back on and water restored, I checked every connection carefully. There was a small leak at the 90-degree elbow, so I detached the hot water supply, tightened and rotated the elbow, and rechecked. After that the plumbing held.

Finally I slid the dishwasher into place and secured it to the cabinet. All told it took about three hours from start to finish, including the hardware store run, but the whole process was much less painful than I’d imagined.

The stainless finish adds balance on that side of the kitchen and complements the sink, faucet, and our pendant light. It also has a protective finish that resists fingerprints, which is useful in our home. Functionally the new dishwasher is similar to the old one, but I love the front-facing countdown timer and the clear “clean” indicator—no more calling across the house to ask whether the dishes are dirty or clean.

On a lighter note, while we were taking pictures Clara grabbed a paper towel and went on a wiping spree. She didn’t manage much dishwashing, but she was delighted to help and has clearly learned to smile for the camera on command.

Balance is restored to our appliance triangle, and the dishwasher no longer looks dingy next to our white cabinets. The installation had a few small surprises and took a bit longer than planned, but it was straightforward overall. Have you installed a dishwasher yourself? Was there an unplanned hardware store trip in your future too?

Psst—check the box from the dishwasher for another fun project idea on our blog.