Mineral deposits can build up in a humidifier over time due to the presence of calcium and other minerals in the water. As the water evaporates, minerals form in the tank, water tray, filter basket and other components within the humidifier, depending on the model. Certain acids can effectively dissolve calcium and other minerals. Because white vinegar is a solution of acetic acid and is safe to handle, it is an excellent cleaning agent for removing mineral scale within a humidifier.
Turn the humidifier off and unplug the unit from the wall socket.
Remove the water tank from the humidifier base. Remove the motor housing, if your humidifier has one, from the base. If your humidifier has a separate water tray or filter basket, remove it as well. Remove the filter from either the water tray or the filter basket and set it aside.
Fill the humidifier base or separate water tray with undiluted vinegar. If your humidifier has a filter basket, place the basket in a sink and fill it with undiluted vinegar. Open the cap on the water tank and fill the tank with undiluted vinegar. Allow vinegar to remain in these parts for between 20 and 30 minutes.
Clean the inside of these parts with a clean cloth and the vinegar already in a components. Use a cotton swab to remove any scale you cannot reach with a cloth.
Rinse the vinegar from each of the humidifier parts with clean, warm, running water. Dry the components thoroughly.
Replace the water tray or the filter basket back into the humidifier base. Replace the filter in the water tray or filter basket. Replace the motor housing and the water tank.
Honeywell and Vicks recommend cleaning your humidifier once a week with vinegar to keep it operating at optimal efficiency.
Do not wash the filter with vinegar. This will damage the filter.