Mold Problems With Top Loader Washing Machines

You can easily tell when mold has become a problem in a top-loading washing machine because the washer and the items washed inside begin to smell bad. This musty smell is a strong indicator that mold has developed in the washer and attention is required. The mold must be cleaned out of the washer and the cause of the mold resolved to prevent the problem from continuing.

...
Remove wet items from the top-loading washing machine promptly after use.

Wet Items

Mold develops or flourishes when damp or wet items are left inside the washing machine for a period of several hours or even days. Remove items from the washing machine promptly after the wash is complete as the warm, dark environment is a prime breeding ground for mold.

Detergent Use

While the use of laundry detergent in a washing machine seems harmless, not using the laundry detergent correctly can actually cause problems. If the washing machine is an energy-efficient top-loading model, high-efficiency laundry detergent should be used at all times. In addition, only the amount instructed on the laundry detergent should be used for every wash load. The use of regular detergent in an energy-efficient washer or overfilling the washer with too much detergent can leave a residue in the tub, which can get damp and develop mold.

Cleaning Energy Efficient Washing Machines

Energy-efficient washing machines can be cleaned with the use of a washing machine cleaner. These tabs are sold in many hardware, home retail or appliance stores and are placed in an empty washing machine. Choose the highest temperature cycle possible or the "Clean Washer" option if available. Leave the washer lid up as much as possible to dry out the washer when not in use.

Cleaning Other Washing Machines

Cleaning mold out of traditional washing machines is accomplished by adding 1 cup of liquid chlorine bleach to the empty washing machine tub. Run a complete hot water wash. Wipe down the tub with a clean, damp cloth to remove any cleaning residue, and then dry with another cloth. Again, leave the lid open as much as possible when the washer is not in use to allow for the tub to air out.