Presence of automatic features. Location of unit for convenience of use and ease of maintenance. Batch or continuous process mode of operation. Storage containers can be glass, metal, or plastic. Each type of container is satisfactory when cared for as the manufacturer directs.
Large distillers can distill about one-half gallon of water per hour.
Smaller units produce less than one quart of water per hour. The cost of producing distilled water depends on the appliance and the local electric rate. Although the distiller has no parts to replace, it is not maintenance-free. Scale must be removed from the boiling tank. Frequency of cleaning the distiller varies with the quantity of impurities in the water and the amount of water distilled.