Most built-in dishwashers in North America share the same standard size, which makes replacing an old one a realistic DIY job. It involves water, a drain and electricity, so take your time and follow the manufacturer’s installation guide, which always has the final word.
Before you buy
- Measure the opening: standard units are 24 inches wide, about 34 inches high (adjustable with the legs) and 24 inches deep. Compact 18-inch models also exist.
- Check how the old one is powered: plugged into an outlet under the sink, or hard-wired into a junction box.
- Check whether the new one comes with a power cord, a water supply line and a 90-degree elbow fitting. Many do not.
Remove the old dishwasher
- Turn off the circuit breaker and close the hot water valve under the sink.
- Remove the lower kick panel. Disconnect the wires in the junction box (or unplug it) and the water line. Keep a towel and shallow pan underneath.
- Disconnect the drain hose from the sink drain or garbage disposal.
- Remove the screws that attach the dishwasher to the countertop or cabinet sides, lower the legs and slide it out.
Install the new one
- Attach the elbow fitting to the dishwasher’s water inlet using thread sealant or tape as the manual says, and connect the power cord or prepare for hard wiring.
- Run the drain hose and water line through the cabinet hole and slide the unit in, without kinking the hoses.
- Connect the drain hose with a high loop or an air gap, as required by your local code. Both prevent dirty sink water from flowing back into the dishwasher. If it connects to a disposal, make sure the knockout plug inside the disposal inlet has been removed.
- Connect the water supply and the electrical connection, matching wire colors and connecting the ground.
- Level the dishwasher with its adjustable feet, then screw the mounting brackets to the counter or cabinet.
Test it
Turn the water on and check for leaks before closing the kick panel. Restore power and run a short cycle while you watch the connections. A small drip at a compression fitting usually just needs a quarter turn.
Choosing the model
Noise level, third rack, drying system and cycle length differ a lot between models. ENERGY STAR certified dishwashers use less water and energy. For a comparison, see the different types of dishwashers and their features, and for the rest of the kitchen, how to choose the right kitchen appliances.
