This happens to be one basic maintenance required for the front-load Whirlpool and Kenmore washers. It is actually quite simple and should not take more than an hour from start to finish.
After disconnecting the washer from the electrical socket, remove the lower front panel by unscrewing the 3 “T-20 torx” screws. Place a large rag under the washer to soak up any excess water. Then remove the cap at the front of the washer to expose the pump filter. Clean these parts in bleach and reinstall them. Next, remove the detergent tray and clean with bleach, as well as the tray compartment.
Finally, wipe the gray door gasket on all 3 sides with a bleach-soaked rag. Once you are finished, run a wash with hot water and add bleach. This will kill all the mould and make your machine smell like new.
To prevent the reoccurrence of mold, some routine maintenance should be carried out every few months. It’s also a good idea to keep the door and detergent tray open in between washes in order to air out the pieces and prevent future mould formation.
Salt works fairly well at neutralizing mould spores; use approximately two cups of table salt in warm water and run a full cycle on low water. You will find that any mil dewy smells will be removed. You can also try approximately two cups of bleach (without laundry), which is comparably effective in removing mould and any associated odour.