How do washing machines get clothes clean?

The first thing you see when you open the lid or door to your washing machine is a large drum. The inner part of the drum that you see is often called the basket. The perforations along the drum drain water. The outer part of the drum that you can't see is the tub, a solid compartment surrounding the basket that keeps water in or allows it to drain out. The basket can move but the fixed tub cannot.

Hoses and pumps move water through the washing machine. When you install the washing machine, you hook hoses up to both hot and cold running water. Another hose takes wastewater that drains from the machine and sends it to a sewer drain pipe. You'll find hot and cold water spigots and a drain pipe ready to use in just about any modern laundry room.

An electric motor in the washing machine moves the basket. If you pick up the repair guide for a washing machine, you'll find detailed terminology and phrases similar to those found in the shop manual for your car. You'll see parts mentioned including belts, hoses, clutch, transmission and even brakes. The motor knows what to do based on the wash program you choose from the buttons and dials on the machine. A combination of digital and mechanical parts carries out that program.

Dispensers let you add detergent, bleach and fabric softener before you start the washing machine so the machine can dispense each of them automatically at the right time. Using dispensers ensures that the detergent mixes thoroughly with the water. Plus, automated dispensers keep clothes from getting spotted by a concentrated splash of bleach or fabric softener.

Washing machines for your home fall into two categories: top-loading and front-loading. They each share the common parts described here, but they have some important distinguishing attributes. Washing machines for industrial use, such as in hotels and hospitals, have a lot of the same features on a much larger scale.

While mechanical features are common to almost all washing machines, not all washing machines wash your clothes in the same way. There are two main types of washing machines you might have in your home or find in a laundromat: top-loading and front-loading washers. A top-loading machine has a lid on top and an upright basket. The other type is front-loading, which has a door on the front and a sideways-mounted basket. There are benefits and drawbacks to both types.

Top-loading washing machines use an agitator to move clothes around the basket. The agitator is a vertical device in the center of the basket with ridges that help push the clothes. The agitator alternates directions on that vertical axis. This movement creates the friction the top-loading machine needs to loosen dirt from fabrics. Some washers also have a fabric-softener dispenser mounted on the top of the agitator.

Front-loading washing machines use paddles that extend a short way from the sides of the basket inward toward the center. The paddles help move the clothes and stir the water while the basket turns. Like the agitator in top-loading machines, the paddles loosen dirt from fabrics by creating friction.

High-efficiency front-loading washing machines are growing in popularity because of their low environmental impact. This is because they use less water and detergent to clean the same amount of clothes as the top-loading machine. One disadvantage they have, though, is that they seal and lock at the beginning of the wash program, and you cannot open many of them again until the end. You can open the lid on a top-loading machine, though, at any time you need to check the load or add something.

The U.S. Environmental Protection Agency and the U.S. Department of Energy have put pressure on appliance manufacturers to produce energy-efficient models. Through their Energy Star program, they identify products that meet a target level of efficiency. Most high-efficiency washing machines are front loaders. Manufacturers recommend only using detergents designed for high-efficiency washing machines because they don't fill the washer with excessive suds.

A washing machine has one or more programs from which you can choose. Sometimes referred to as cycles, you should be able to find these described in the owner's manual. Each program is a sequence of stages with varied times, speeds and temperatures. Each stage may also be called a cycle. For this article, we'll define cycle to mean the individual stages and use the word program to mean some combination of those stages.

The following are descriptions of the cycles you might use on your washing machine:

These cycles make up parts the following common programs, identified here by what makes them unique:

Depending on your washing machine, you may be able to control certain program details like water level and temperature manually. Many high-end washing machines also use sensors to automatically adjust the water level, cycle length and spin speed based on the size and bulk of the load. Use your owner's manual to find all your program and cycle options.