You never want to open your washing machine and find suds lingering inside the machine and on laundry. Suds undoubtedly mean that you need to repeat the wash cycle to rid laundry of soap. Perhaps the best way to reduce suds is to use less detergent. In general, the more soap that's used, the more suds are produced in the washing machine.
One of the best ways to prevent suds in a washing machine is to use less detergent. The general rule is that soft water demands less soap than hard water. If you have soft water, use about half as much soap for the same size wash load washed with hard water. Increase the detergent amount gradually until you reach a quantity that reduces suds but still gets clothes clean. Adhere to directions on the side of the laundry detergent package for amounts to use in each wash load, but don't be afraid to modify quantities slightly depending on your water quality.
No or Low Phosphate Detergent
Phosphate is what enables detergents to produce suds when detergent combines with water. A detergent with less phosphate produces fewer suds than one with more. Different detergent brands contain various percentages of phosphates, and high-efficiency (HE) detergents contain the least amounts of all detergents although variations exist among manufacturers as well. Certain laundry detergents are even phosphate free. Switch to a no or lower phosphate detergent to lessen the quantity of suds generated in your washing machine. Compare detergent labels to ascertain the percentage of phosphorous used in multiple detergent products.
A HE detergent is formulated for front-loading washing machines that use less water than top-loading machines. The detergent is designed to produce fewer suds than conventional laundry detergents and contains lower amounts of phosphates than a conventional detergent. Use a HE laundry detergent if you want to reduce the amounts of suds in your washing machine.
White distilled vinegar works to reduce suds in a washing machine. If your washer finishes the rinse cycle and you open the door to find suds remaining inside, add 1/2 cup of vinegar in 1 qt. of water to the washing machine, and set it to "rinse." The vinegar will rid the washer and laundry of remaining suds and ensure your laundry comes out clean.