A continuous-feed garbage disposal installs beneath the sink and connects to the drain hole and dishwasher (if you have one). It normally operates by a switch that's installed in the wall backsplash or inside the sink cabinet that activates the blades. The garbage disposal's blades grind up food waste deposited in the drain hole while water is simultaneously run from the faucet to wash the scraps down the drain. Because continuous-feed garbage disposers require both plumbing and electrical work (the latter to install the switch), they aren't really good do-it-yourself projects unless you're experienced or are simply replacing an existing garbage disposal.
Garbage disposals are available in different horsepower ratings -- usually 1/2, 3/4 or 1 horsepower. In theory, higher-horsepower units should be handle larger amounts of waste more quickly, but tests at ConsumerReports.org show that isn't always the case. Just because a garbage disposer has a higher horsepower rating doesn't necessarily mean it will work better than a lower-horsepower unit. If you want to grind bones, you will want a better-performing 3/4- or 1-horsepower unit, but if you think you'll mainly grind up softer foods, a well-rated 1/2-horsepower garbage disposal should suffice.
According to one professional review, the 2,800-rpm motor that powers the Waste King Legend 8000 1 Horsepower Disposer (*Est. $150) is fast and efficient at grinding beef bones and vegetables. Stringy celery is a notorious problem for garbage disposals, but the Waste King Legend 8000 grinds through them without clogging. In the event of a jam, the Waste King garbage disposal's removable splashguard makes it easier to unblock. Waste King offers a lifetime warranty on the Legend 8000 disposal, which features stainless-steel grinding components and a corrosion-resistant grinding chamber. This warranty includes in-home service and replacement.
The majority of owners posting user reviews at Amazon.com agree the Waste King Legend 8000 is quieter than they anticipated, fast-working and easy to install. This garbage disposal's EZ Mount design installs without screws, and the flange simply drops in place on top of a gasket if you have stainless-steel sink (no plumber's putty needed). You should make sure you have the necessary space under your sink before buying the Waste King Legend 8000, however; it's a pretty large garbage disposal, measuring 16.1 inches tall by 8.5 inches wide.
If you are willing to pay more for a quieter garbage disposal, one professional review says the 3/4-horsepower KitchenAid Superba KCDS075T (*Est. $250) is among the quietest models tested. This may be due, in part, to a slightly slower grinding speed than the Waste King garbage disposals tested. However, the KitchenAid garbage disposal's 3/4-horsepower motor and stainless-steel grinding components perform comparably when disposing of meat bones and vegetables. The KitchenAid KCDS075T disposal is more compact (12.75 inches by 9 inches) compared to the Waste King Legend garbage disposer. We found the most owner reviews on this model at retailer ABT.com as well as a small number of reviews at Amazon.com. Owners agree this KitchenAid Superba garbage disposal is powerful, quiet and easy to install. Warranty coverage is shorter than Waste King's at five years, and it doesn't provide for in-home servicing.
If you aren't frequently grinding hard foods with a garbage disposal, you may be able to spend under $100 for one with a 1/2-horsepower motor. Jamming is a major concern with less powerful garbage disposals, but their smaller size is a better solution for cramped under-sink spaces. Several garbage disposals earn praise from owners, but the Waste King Legend 2600 1/2 Horsepower Disposer (*Est. $75) is a standout for its stainless-steel grinding components and five-year, in-home warranty. In fact, horsepower and warranty aside, it has the same features as the Best Reviewed Waste King Legend 8000 garbage disposal at about half the cost.
If compactness is of utmost concern, the KitchenAid 1/2 Horsepower Continuous Feed Disposer KCDB250G (*Est. $100) may be worth a look, as it measures 11.4 inches by 6.7 inches. The KCDB250G garbage disposal receives good reviews from owners posting at ABT.com, but its grinding blades are made of galvanized steel, rather than stainless, and the warranty is for only one year. In this regard, it doesn't compare to the Waste King Legend 2600.
InSinkErator Badger garbage disposals are often installed by builders; however, you may want to think twice about installing one as a replacement. One professional review found the InSinkErator Badger 5 (*Est. $100) to be louder than the other 1/2-horsepower garbage disposals tested. It also doesn't grind vegetable scraps as well as any of the other garbage disposals. The Badger 5 receives a lower average rating from owners at Amazon.com, Lowes.com and HomeDepot.com. Dissatisfied owners say the housing cracked and water began to leak out. The InSinkErator Badger 5 has a two-year in-home warranty. Two other similar models are the 1/3-horsepower Badger 1 (*Est. $80) with a one-year in-home warranty and the 3/4-horsepower Badger 5XP (*Est. $110) with a three-year in-home warranty. Both of these also get low ratings from owners at Amazon.com.
A septic tank is used in homes that are not connected to a public sewer system. It consists of a 750 gallon or larger underground container and a drain field. Solids sink to the bottom of the tank and water flows through the drain field where gravel and soil filter it. Naturally occurring bacteria in the septic tank are important to properly discompose solids. Every few years the sludge in the bottom must be pumped out to keep it from overflowing into the drain field. Homes with a septic tank may want to think twice before having a garbage disposal installed because more food waste going down the drain and into the septic tank means it will need to be pumped more frequently, which is a rather expensive service.
If the septic tank is large enough, adding a garbage disposal may not be a problem. Sometimes, adding a garbage disposal to a new home with a septic tank will void the warranty, so homeowners should check with their builder before installing a garbage disposal. Once a garbage disposal is installed, antibacterial soap, grease and certain types of food waste should not be put down the drain so as to keep the septic system functioning properly.
To combat problems, a few garbage disposals are specifically designed to work with a septic system. The InSinkErator Evolution Septic Assist (*Est. $240) is a 3/4-horsepower, continuous-feed garbage disposal with a 1,725-rpm grinding speed. What makes this garbage disposal unique is its Bio-Charge cartridge, which releases a microorganism to help to break down food waste in the septic tank and reduce the buildup of sludge. This means waste won't need to be pumped out of the septic tank as frequently. The Bio-Charge cartridge lasts approximately three to four months, and a replacement costs $13. This garbage disposal's grinding chamber and components are stainless steel, and InSinkErator backs it with a four-year, in-home warranty.
Batch-feed garbage disposals are generally more expensive, but they are the safer choice. That's because the blades only activate after placing a magnetic cover over the top of the drain hole. Fingers can't get caught in the moving blades, and objects can't fall down the drain and cause a jam. Some owners say they prefer this design that doesn't require flicking an electrical switch with wet hands, and there's no cost for installing such a switch. The main drawback is you can't continually push food down the drain, so it takes more time to dispose of a meal's worth of food scraps.
Experts give the InSinkErator Evolution Cover Control 3/4 Horsepower Disposer (*Est. $250) high marks for grinding quickly and quietly. For owners who expect to be in their home for a while, the durability of the Evolution Cover Control's stainless-steel grinding components and chamber may be worth the higher price tag. Reviewers appreciate the compact 13.3-inch height, as well as the ease of installing the Quick-Lock Mount. Owners also say the InSinkErator garbage disposal is extremely quiet, and the InSinkErator hotline is helpful with installation questions. This garbage disposal comes with a seven-year in-home warranty that covers parts and labor. If you don't want to hardwire the garbage disposal, because you have an outlet under the sink, a power cord must be purchased separately for under $10.
One professional reviewer says the Waste King Legend 8000TC 1 Horsepower Disposer (*Est. $185) grinds food waste more finely than the InSinkErator Evolution Cover Control, but isn't as quiet. At just over 18 inches tall, this garbage disposal is the largest one we cover in this report. It has stainless-steel blades that rotate at 2,800 rpm and a removable splashguard and is backed by a 10-year, in-home warranty. There are only a handful of user reviews posted at Amazon.com, where owners say it's quiet and powerful.