Swapping out an old dishwasher for a new one is a job many hands-on homeowners can handle. It requires basic knowledge of plumbing and electrical systems. Learning how to replace a dishwasher can save time and money, but it is critical to approach the work with safety as the top priority. Working with water lines and wiring demands careful attention.

For someone unsure how difficult the task is or debating whether to fix the old unit or buy a new one, knowing when to stop and call for help is a sign of good judgment. If the job becomes unexpectedly complicated or if you encounter a major obstacle, bringing in a trusted expert is always the smarter choice to prevent costly damage.

What You Need Before You Replace a Dishwasher

Before beginning the project, ensure you have the right tools, materials, and safety measures in place. A bit of preparation at the start helps everything go smoothly and prevents unnecessary mess.

Tools You’ll Need

Having the correct tools makes a big difference. Gather these items:

• Adjustable wrench
• Phillips and flathead screwdrivers
• Voltage tester
• Pliers
• Bucket or towel (for catching water spills)
• Level

Materials Checklist

In addition to tools, you will likely need to replace or reconnect a few key items:

• New water supply line
• New drain hose
• Power cord (or hardwiring kit, if required)
• Mounting brackets
• Teflon tape or plumber’s tape

Safety First: What to Know Before You Start

Always shut off the power at the breaker and turn off the water supply valve, usually located under the sink, before touching anything. Use a voltage tester to confirm the power is truly off. Even if the person doing the work is confident in DIY abilities, skipping safety steps can easily lead to leaks, electrical shocks, or worse. Take the extra time to double-check everything before moving forward.

How to Remove Your Old Dishwasher

Removing the old unit safely and carefully is the first step. Here is a guide to getting it out without damaging the surrounding cabinetry or floor.

Step 1: Turn Off Utilities

The process starts at the breaker box, where you cut power to the dishwasher. Next, shut off the water supply, which is typically under the kitchen sink. Failing to do this could lead to electrical shock or flooding. Never take that risk.

Step 2: Disconnect the Water and Drain Lines

Once all utilities are shut off, disconnect the plumbing.

• Place a towel or bucket beneath the dishwasher to catch any residual water.
• Use an adjustable wrench to loosen and remove the water supply line.
• Take the drain hose off the sink connection or garbage disposal.
• Inspect both lines for wear or cracks. Replacing them now can save future trouble.

Step 3: Unhook and Slide Out the Old Dishwasher

The unit is now ready to come out of the cabinet space.

• Unscrew the mounting brackets that hold the dishwasher in place under the counter.
• Carefully wiggle the unit forward. Do not yank or drag it, as this can damage the floor or cabinetry.
• Lay down a towel or a piece of cardboard to protect the floor from scratches.
• Disconnect the power supply and check that no wires are exposed or insulation is damaged.

How to Install a New Dishwasher the Right Way

With the old unit gone, it is time to set the new one in place. A strong install means avoiding future issues, especially with leaks or electrical trouble.

Step 4: Prep the Installation Area

Before installing the new dishwasher, clean the empty space and remove any debris or leftover hardware. Measure the opening one last time to confirm the new unit fits. Check the floor with a level and ensure there is enough clearance from the walls and cabinets. A little preparation here can prevent major headaches later on.

Step 5: Attach Water Line and Drain Hose

Begin by connecting the water supply line to the inlet valve. Use Teflon tape to properly seal the threads and prevent leaks. Attach the drain hose to either the sink drain or garbage disposal, depending on the current setup. It is important to create a high loop or air gap in the hose to prevent dirty water from flowing back into the clean unit.

Step 6: Connect the Electrical Wiring

If the new dishwasher uses a power cord, simply plug it into a nearby outlet. For hardwired connections, match the black wire to the black (hot) wire, the white wire to the white (neutral) wire, and the green wire to the bare copper (ground) wire. Secure all wire nuts tightly. A bad connection can easily trip breakers or even damage the appliance itself.

Step 7: Slide In and Secure the Dishwasher

Gently slide the new dishwasher into its opening. Be careful not to pinch any wires or hoses underneath. Use a level to make sure the unit is perfectly even on all sides. Once aligned, screw in the mounting brackets to keep it securely in place. Proper leveling prevents excess noise and ensures even water drainage during the cycles.

Step 8: Test Your New Dishwasher

Turn the water and power back on. Run a short wash cycle to test the connections. Check underneath and behind the unit immediately for any sign of leaks. Listen for unusual sounds and confirm that the dishwasher is filling, draining, and operating as expected.

Common Mistakes to Avoid When Replacing a Dishwasher

Even a basic swap can go wrong if someone overlooks key details. Be careful to avoid these common errors:

• Forgetting to shut off all power or water connections.
• Over-tightening water or drain line connections, which strips threads and causes leaks.
• Skipping the leveling step, which leads to noise or poor washing and draining performance.

When Should You Call a Professional Installer?

Not every install is a simple process. Here are times when it makes sense to hand the job over to an expert:

• The kitchen has old or non-standard plumbing setups.
• The electrical wiring is complex or unfamiliar.
• Tight or custom-built cabinetry limits access to the work area.
• The homeowner wants to ensure the product warranty remains protected.

Frequently Asked Questions

How long does it take to replace a dishwasher?

Most standard replacements take about 1.5 to 2 hours, assuming all parts are ready and the existing setup is in good shape.

Can a person install a dishwasher without a plumber?

Yes, if the person is comfortable with basic plumbing and electrical work, DIY installation is certainly possible.

Does a person need a permit to install a dishwasher themselves?

In most places, no permit is required for a direct replacement. However, local codes and regulations can vary.

Is it cheaper to install a dishwasher oneself or hire someone?

Doing it oneself is usually cheaper upfront, but hiring a professional prevents potentially costly mistakes.

What’s the difference between installation and replacement?

Installation is for new construction or adding an appliance where one didn’t exist before, while replacement involves removing the old unit first.

Need Help? Call Wilshire’s Dishwasher Experts Today

Not every dishwasher swap is as simple as it looks, and sometimes it’s just not worth the hassle. Wilshire’s factory-trained technicians handle the entire process with precision, from safe removal to warranty-friendly installation. If your kitchen setup is older or more complex, getting help now can save you from expensive damage later. Call (818) 898-9999 or book an appointment online to get started. We’re local, reliable, and here to make the job easy.