If you use your slow cooker regularly, the inside will eventually get dirty. Things spill or get on the outside of the liner. I’ve spent countless minutes scrubbing when I could’ve been using common household ingredients to do the dirty work.
Over at One Good Thing, they talk about putting a small bowl of ammonia in the cooker, then putting the lid on to let the fumes destroy that gunk. No need to plug it in, just let the fumes do their thing. This isn’t for cleaning the liner, those are usually dishwasher safe. It’s just for the inside of the actual cooker.
A Simple Way to Clean the Inside of Your Slow Cooker | One Good Thing