Mildew
Considering mildew needs moisture and darkness to survive, it’s not surprising that mildew can make it into the washing machine. Front-loading washing machines are notorious for mildew problems as the seals around the door collect residual soap and debris, providing a food source for mildew. If you notice a musty smell, check around the seals for this black and white fungal residue.
Remove of Mildew
Wear gloves, a mask, and protective glasses while dealing with mildew to protect yourself. Dip a soft- to medium-bristle brush into soapy water. Use just enough powdered laundry or dishwasher detergent to make the water sudsy. Scrub the seal around the door. Dip a sponge or cloth into the soapy water to wipe down the inside of the washing machine. Rinse the door seal with clean water to remove any residual soap or debris.
Removal of Odor
Turn on the empty washing machine and run a cycle of hot water with 2 cups of white vinegar or chlorine bleach. If the smell is still strong after the cycle, run a second cycle. Open up the door and allow the washing machine 30 to 45 minutes to air dry before closing it back up.
Burning or Other Smells
Check the hoses and the drain around the back to make sure there are no leaks. If the tub takes a long time to fill with water, a clog in the hose may be the source. Unplug the washing machine and remove the back panel. Refer to the manufacturer's instructions and guidelines here. Disconnect the hot and cold water hoses and use a wet-dry vac to clean them out. Reconnect the hoses and replace the back panel before plugging the washer back in and turning it on for a cycle to help clear any residual in the hoses. If your Bosch washing machine starts producing a burning smell, turn it off and unplug it immediately. Contact the manufacturer for further instructions.