Put bacon and onion in a big frying pan. Cook on medium-high heat until the bacon is cooked through and the onions are tender. Remove extra fat.
Put the bacon and onion in a slow cooker. Add chicken broth, water, potatoes, salt, dill, and white pepper. Cover the dish and cook on low heat for 6 to 7 hours, stirring from time to time.
In a little bowl, mix the flour and half-and-half using a whisk. Mix into the soup with the evaporated milk. Cover the dish and cook for an additional 30 minutes before serving.