Removing scale deposits from a humidifier involves loosening the scales with a vinegar solution, wiping the loosened scales off the unit and rinsing the unit. Be sure to disconnect the unit from electric power to prevent a possible electric shock before attempting this task. Undiluted white vinegar, a soft-bristled brush and a soft, clean rag are handy in this task.
Start by pouring water into the bottles of the humidifier, taking care not to fill the bottles completely. For a humidifier that features a water tank instead of bottles, pour the water into the tank until the tank is almost full. Pour water into the humidifier's base until the base is half full. Add four ounces of white vinegar into the water in the bottles or tank. Add four ounces of the same solution into the water in the unit's base as well. Allow the solution to sit in the humidifier's components for 20 minutes before emptying them.
Soak the rag with the vinegar, and use the rag to clear the base of the scales by wiping. Rub away any stubborn scales with the brush. Repeat the process for the tank or bottles before clearing the unit of the cleaner residue with clean water. Blot the unit dry with a dry, soft cloth to complete the process. To ensure that the unit works efficiently, it is advisable to clean it with a vinegar solution at least once a month.