After having used it for hours and hours, your washing machine needs some care and attention so it can keep up working properly. In each cycle sediments and dirt can be found in the places where water comes in and out.

Personally I believe it to be a silent infectious source for all your clothes, so I prefer doing this once every three months to prevent further deterioration.

Clean your washing machine naturally:

1. Fill the washing machine with hot water and pour 2 cups of white vinegar for an hour: vinegar is safe to use in both standard and high-efficiency washers and is beneficial to septic tanks and the environment. All types of vinegar contain acetic acid that works to brighten, soften, and kill odors in your laundry.

2. Program a full cycle and let it go with that water : to clean the inside of a washing machine, carefully fill the machine with hot water from the tap. Then, add 1 quart of bleach to the machine to remove stains and marks from the inside. Wet a rag or sponge with an all-purpose cleaner, and wipe down the rubber seal on the door to remove mold and mildew growth. 

3. Fill the washing machine again and add 2 cups of baking soda for an hour: since baking soda is dry, it should not be placed in the automatic detergent dispenser with your regular detergent. The baking soda can cause clumping and clog the dispenser. … If you have particularly smelly clothes, using a full cup of baking soda will not harm your washer

4. Start the cycle again to finish the process.