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Replacing Your Dishwasher

Dishwasher on its last legs? When you buy a new one, pocket the installation fee by doing the job yourself.

Richard Trethewey installs a new dishwasher
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Introduction

 

Introduction

Dishwashers have come a long way since Illinois socialite Josephine Cochrane invented back in the 1880s what later became the KitchenAid. Still, they don't last forever. Removing an undercounter dishwasher and replacing it will take an experienced installer less than an hour. You probably won't manage the job that quickly, but it is a relatively simple procedure, especially because the plumbing and electrical hookups are already in place. And by doing the work yourself, you can save the $100 or more a retailer will charge, or step up to a model with more features. Dishwashers come in a variety of price ranges and styles (see Dishwasher Options), but all standard machines fit in a 24-in.-wide opening. So no matter which model you choose, you won't need to modify cabinets.

Dishwashers have come a long way since Illinois socialite Josephine Cochrane invented back in the 1880s what later became the KitchenAid. Still, they don't last forever. Removing an undercounter dishwasher and replacing it will take an experienced installer less than an hour. You probably won't manage the job that quickly, but it is a relatively simple procedure, especially because the plumbing and electrical hookups are already in place. And by doing the work yourself, you can save the $100 or more a retailer will charge, or step up to a model with more features. Dishwashers come in a variety of price ranges and styles (see Dishwasher Options), but all standard machines fit in a 24-in.-wide opening. So no matter which model you choose, you won't need to modify cabinets.

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Removing the Old Machine

 

Removing the Old Machine

loosen compression fitting; d-i-y dishwasher installation
Smith/Baer
After removing the access panel at the front of the dishwasher, loosen the compression fitting that connects the hot-water supply line and pull the line out.

First, shut off the water and power to the machine. The dishwasher should have its own shutoff valve in the cabinet under the kitchen sink. But installers like Fred Schlott, an assistant manager at The Home Depot in Port Chester, New York, and the pro doing the installation seen here, cautions against trusting this valve completely. After sitting in the open position for years, an inexpensive valve can spring a leak when disturbed, or internal corrosion may make it nearly impossible to close. If that's the case, turn off the water for the house and replace the dishwasher shutoff. As for the power, because built-in dishwashers often are hard-wired (not a "pigtail" that's plugged into a receptacle), you should turn off the power at the main electrical panel or, if you have one, at the cutoff switch near the appliance. Your dishwasher is connected to a hot-water supply line, a discharge line and an electrical feed, all of which must be disconnected. You'll find the supply line and electrical connections in the cramped space between the bottom of the dishwasher tub and the floor. To get at them, remove the access panel at the bottom of the dishwasher, which is held in place with a few sheet-metal screws. The water-supply line ends at an elbow near the left front corner of the machine. Use pliers or an open-end box wrench to loosen the compression fitting. A shallow dish or a rag will catch the small amount of water left in the line. Inside a metal junction box you'll find a pair of wire nuts connecting black and white wires from the power feed to the machine. A bare ground wire should be connected to the box with a green screw. Disconnect them all; save the wire nuts and the box connector for the new power feed. One thing to watch for: Dishwasher installations in new construction are required to have a dedicated 20-amp circuit with 12-ga. wire. If the cable is undersize or the equipment ground is missing, you may want to hire an electrician to upgrade the circuit. You also need to disconnect the dishwasher drain line from the sink drain or garbage disposer. It's usually held in place with a hose clamp. Replace this discharge line when you put in your new dishwasher (you'll get one with the machine). With plumbing and wiring lines disconnected, all that's left are two screws attaching the dishwasher to the underside of the counter. The two metal clips holding the machine in place are visible with the door open. Once these have been removed, ease the dishwasher out of its opening. It will be easier to remove if one person feeds the drain line through the hole in the side of the sink cabinet as a second person wiggles the old machine out. It can be a tight squeeze. If you find water damage to flooring in the dishwasher cavity caused by a leak in the tub, supply line or discharge hose, repair the flooring before installing the new unit.

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Setting Up the New Machine

 

Setting Up the New Machine

make wiring connections; d-i-y dishwasher installation
Smith/Baer
You make wiring connections in a metal junction box at the front of the appliance. Make sure you turn off power to the appliance before touching any electrical connections.

With the new dishwasher uncrated and lying on its back, attach a new elbow for the water-supply line. These are called, conveniently enough, dishwasher elbows. One side has a standard 3/8-in. plumbing thread; the other side accommodates the nut of a 3/8-in. compression fitting. When the elbow is installed, it should face backward so it can be reattached to the supply line. This orientation is crucial, and it sometimes means you can't tighten the elbow as much as you would like. To lessen the chance of a leak at the fitting, Schlott recommends giving the elbow a couple of extra wraps of Teflon tape before inserting it (four wraps in all). Wrap the tape firmly in a clockwise direction. In this installation, Schlott did not change the 3/8-in. flexible copper supply line because it was in excellent shape. But inspect your line carefully and replace it if it looks kinked or worn or shows signs of leaking. You can replace the copper line with an easy-to-work-with braided-metal supply line, available at home centers and plumbing-supply houses. With the new discharge hose threaded into the hole in the side of the cabinet, carefully move the new machine into the opening. To avoid denting the front panel, don't push with your knee. As you ease the machine in place, work the discharge line through the cabinet side. If the line gets kinked the new machine will not work properly. Hook up the plumbing first. If there's a leak, it's easier to pull the dishwasher back out without worrying about the electrical connections. The old compression fittings will still be attached to the supply line (if you didn't replace it), and you won't be able to remove them. If there's any excess supply line, Schlott often cuts it back an inch or two and replaces the ferrule and nut of the compression fitting with new parts. Tightening this compression fitting is not the place to prove how strong you are; overtightening can make it leak. "It's a feel thing," Schlott says. In this installation, for example, the fitting dripped slightly when the water was turned back on. Schlott reapplied his pliers and tightened it slightly—a quarter turn or so. The drip stopped. "Once a drip is down to a minimal thing," he says, "I just creep up on it." After you make the plumbing connection and test it by turning on the water, reconnect the wiring and reattach the discharge line under the sink. To protect the dishwasher from sink backwash, loop the drain line to the highest point in the sink cabinet and attach it with a clamp or plumber's strap. Local codes in some areas require the use of an air gap, a device that prevents backflow into the dishwasher. If this is required in your area, mount the air gap on the back edge of the sink to the right of the faucet. Use the adjustable feet on your machine to help you level it in the opening. You can also use them to adjust the height of the dishwasher, minimizing the gap between the top of the machine and the bottom of the counter. The face of the dishwasher should be plumb, and the appliance should not interfere with any drawers or doors in adjacent cabinets. Once the dishwasher fits properly, screw the metal clips at the top of the machine to the underside of the counter to complete the installation. One last step: Run the machine through a cycle or two before reattaching the front access panel just to make sure there are no leaks.

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Dishwasher Options

 

Dishwasher Options

back off screws holding dishwasher to countertop; d-i-y installation
Smith/Baer
Back off screws that hold two metal tabs to the underside of the countertop. If you have disconnected electrical and plumbing lines, you can now ease the dishwasher
out of the opening.

Undercounter dishwashers range in price from less than $200 to nearly $1,200, and some European models cost even more. They all clean dishes, but an economy dishwasher —something in the $200 range —is likely to have an on/off switch and not much else. More expensive models clean more thoroughly and efficiently. They offer greater capacity and loading flexibility, more water-temperature options, better filtration systems and advanced electronic sensors. Higher-priced machines also have stainless-steel tubs instead of plastic ones. KitchenAid is typical in its pay-more-get-more approach. It makes five undercounter models, ranging from $549 to $1,149. All of them have stainless-steel tubs, hold 14 place settings and come with nylon-coated racks. The top-of-the-line model offers, among other things, two more wash cycles, more flexible racking and a cycle for sanitizing dishes. Dishwashers are getting quieter, although delay settings on some machines make this issue less important. "The sound game is not over," says David Hoyh, director of Whirlpool's dishwasher line, "but it's almost to the point where the consumer doesn't detect the dishwasher is running." There is, however, no industry standard on noise, so you are left with vague promises implied by model names. Some makers measure dishwasher noise in sones. Unlike the decibel scale, which is an objective measurement of sound pressure, the sone scale reflects the perception of loudness and is intended to gauge the annoyance factor of different types of sound. Not all manufacturers publish a sone rating, but as a point of reference the quietest dishwashers on the market operate at about 4 sones. Machines with the Energy Star label exceed minimum energy standards by at least 25 percent. But don't expect dramatic savings here. The most efficient dishwasher on the Energy Star list uses an estimated 344 kWh of energy per year—roughly half the consumption of the most energy-hungry model. At 8.5 cents per kWh, the savings would amount to about $2.50 per month. On the other hand, if all U.S. homes were to use Energy Star appliances, in 15 years the money saved by decreased energy usage would total $100 billion nationwide. A complete list of Energy Star machines is available at www.energystar.gov.

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Where to Find It

 

Where to Find It

installing dishwasher elbow joint; d-i-y
Smith/Baer
Install a new dishwasher elbow at the solenoid valve with the uncrated appliance lying on its back. A little extra Teflon tape will help to seal the joint.

Amana
2800 220th Trail
Amana, IA 52204
www.amana.com
800/843-0304

Asko USA
Box 851850
Richardson, TX 75081
www.askousa.com
800/898-1879

GE Appliances
AP 6 Room 129
Louisville, KY 40225
www.geappliances.com
800/626-2000

Maytag
240 Edwards St.
Cleveland, TN 37311
www.maytag.com
800/688-9900

Miele
9 Independence Way
Princeton, NJ 08540
www.mieleusa.com.
800/843-7231

Whirlpool
2000 M-63N
Benton Har-bor, MI 49022
www.whirlpool.com
800/253-1301

 
 

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