It Is Easy to Replace a Garbage Disposal

Dear James: With three children, my old garbage disposal gets a good workout. After 10 years, it finally gave out. Is this something that I can replace myself? If so, please give me some tips on doing it. — Aimee G.

Dear Aimee: Installing a garbage disposal is easily within the skill level of even the most inexperienced do-it-yourselfers. The only problem that you may encounter is having enough strength to hold it in position under the sink while installing it. It is a bit awkward for most women to reach in under the sink and hold it up in position.

Since your children are probably the ones that wore it out by dropping spoons, cherry pits, bones, etc., down the drain, have one of the smaller ones help you. They should be small enough to crawl in under the sink. Using both hands, they can easily hold it in place for you to tighten it.

If your old one lasted 10 years, you should feel lucky. Even the best models come with only a seven-year warranty, so apparently you cannot be too hard on your children for its failure. Over time, the constant moisture finally corrodes the internal parts.

Unless you enjoy replacing garbage disposals, it is wise to select a high-quality model. Look for features such as stainless-steel grinding elements, automatic reverse-grinding action and an insulated outer shell for quiet operation. The InSinkErator SS Series has some of the most reliable models available.

Before doing anything else, turn off the electrical power at the main circuit breaker panel. Even though all disposers have a kitchen wall switch to operate it, just switching it off at the wall is not safe enough. It is too easy to bump the wall switch with a long wrench and not even notice that you switched the power on.

First you must remove the old garbage disposal. Disconnect the drain trap from the old garbage disposal’s waste-discharge tube. If you have a dishwasher, too, its drain is probably connected to the garbage disposal. Pile up some old blankets or a pillow under it. Loosen the mounting screws and let it drop onto the blankets. Remove the wiring from it.

Watch carefully how the parts were assembled on your old garbage disposal because most of them mount in a similar manner. You should have a flange, gasket, mounting rings, retaining ring and the disposer unit itself.

Most sink holes are a standard size, so the flange from the new unit should fit perfectly. Take some fresh plumber’s putty and roll it in your hands to form a 1/2- to 3/4-inch rope. Lay this rope on the indentation around the sink hole.

Press the flange firmly down into the putty rope. Make sure that it is centered over the sink hole. Place a heavy object on the flange to hold it in place in the sink while you work from below.

Slip the gasket and the mounting ring up over the end of the flange extending down under the sink. Spread the retaining ring open and slip it up until it snaps into the groove. This locks the flange assembly together. Tighten the mounting screws until the assembly is seated tightly against the sink.

Connect the electrical wiring per the manufacturer’s instructions. In most cases, it attaches exactly like it did to the old one. Lift the disposer up under the flange and attach it. Many of them have mounting tabs so that, with a quick turn, it will hang by itself. Follow the manufacturer’s instructions to tighten it securely and to attach the plumbing connections.

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