How to Install A New Dishwasher With a Double Sink Without a Garbage Disposal

Installing a dishwasher when there is no garbage disposal is no more difficult than it is when there is a disposal present.

Installing a new dishwasher is not as difficult as you may first think. The average do-it-yourselfer can complete the project in three or four hours. The design of the dishwasher allows it to fit in a standard cabinet space 24 inches wide. Assuming that there is existing cabinetry installed, you need only remove the cabinet in the location where you want to install the new dishwasher. When there is no garbage disposal to install, all you will have to do is install a tailpiece with a dishwasher connection. The remaining plumbing for the double-bowl sink is already installed.

Things You'll Need

• Hole saw
• Drill
• Screwdriver set
• Spade bit set
• Pliers
• Tube bending springs
• Adjustable wrench
• Tubing cutter
• Small level
• Wire strippers
• Electrical wire
• Wire nuts
• Tape
• 3/8-inch to ½-inch brass elbow
• Teflon tape
• ½-inch flexible copper tubing
• Two ½-inch compression fittings
• Cable clamp
• Hose clamp
• Pipe strap

Instructions

1. Shut of the hot water supply line to the kitchen sink. Turn off the electrical circuit at the breaker box. Label the breaker so that someone does not turn it on while you are working on it. Make sure the opening in the cabinet space is large enough to accept the dishwasher unit. The typical size is 24 inches wide. Cut a 2-inch hole into the side of the sink cabinet using a drill and hole saw.

2. Uncoil the copper tubing so that it is laying flat on the floor. Insert one end of the copper tubing through the hole that you cut with the hole saw. Place a tube bending spring over the copper tubing near end that you will connect to the water supply line. Bend the tubing using the tube bending springs and shape it so that you can make the connection to the water supply line.

3. Slide a compression fitting onto the copper tubing and then a ferrule. Connect the tubing to the hot water supply line. Tighten the fitting using the adjustable wrench. Install the electrical line to the circuit to which you are connecting the dishwasher. Install wire nuts over the splices where the bare wires are. When you connect the wires, white is neutral, black is hot and green or bare wire is the ground.

4. Measure the lengths of the copper tubing and electrical wire that you need to connect the dishwasher with a tape measure and cut both to that length. Tape them to the floor so that you are able to slide the dishwasher into place without hitting them. Slide the dishwasher into place under the counter, but not all the way back. Tilt the dishwasher back and wrap the water inlet threads with Teflon tape. Use a tube bending spring to shape the tubing toward the inlet.

5. Insert the dishwasher drain line through the hole you cut into the side of the sink cabinet. Slide the dishwasher fully into the bay. Place a compressing fitting and a ferrule on the end of the copper tubing. Connect the water supply line to the dishwasher and tighten the fitting with an adjustable wrench. Insert a cable clamp into the opening on the electrical box of the dishwasher and lock it into place by twisting on the retaining ring.

6. Insert the electrical wire through the cable clamp. Connect the wires to the dishwasher. White connects to white and is the neutral wire. Black connects to black and is the hot wire. Connect the ground wire to the dishwasher ground wire and secure it using a wire nut. Tighten the screws on the wire clamp securing the electrical wire. Place the cover on the wiring box and tighten the screws with a screwdriver to lock it into place.

7. Disconnect the tailpiece from the S-trap using a pipe wrench. Remove the tailpiece from the sink drain. Install the new tailpiece with the dishwasher drain nipple. Connect the S-trap to the new tailpiece using the pipe wrench. Connect the dishwasher drain tube to the new tailpiece using a pair of pliers to loosen the hose clamp. Be sure the drain line has no kinks in it or the dishwasher will not be able to drain properly.

8. Attach the drain tubing to the cabinet wall using a pipe strap, screwdriver and wood screws. Twist the front dishwasher legs clockwise until they are resting on the floor. Check the dishwasher for level using a torpedo level. Adjust the front legs as necessary. Connect the dishwasher to the underside of the countertop using wood screws. Turn the electrical power on to the dishwasher circuit. Turn on the water supply and check thoroughly for leaks.

9. Install the kick plate on the bottom of the dishwasher and tighten the screws with a screwdriver. Run the dishwasher empty for one cycle to test the operation of the unit.

Tips & Warnings

• Never attempt to connect a dishwasher with the power to the electrical circuit on.

References

• This Old House; How to Install a Dishwasher; Harry Sawyers; 2011
• This Old House; How to Install a Dishwasher; Richard Trethewey; 2011
• The Virtual Repairman; How to Install a Dishwasher; 1996-2008