Hydrochloric acid, for example, is very aggressive and so must be used with care. Manufacturers usually recommend a cleaning procedure, product and frequency for their equipment. Portable units typically have 500 to 700 watt heating elements and produce 3 or 4 gallons per day. The larger units have heating elements of 1,000 to 1,500 watts and produce 8 to 12 gallons per day. The largest units for home use operate on 220 to 240 volt current, have heating elements of 2,500 to 5,000 watts, and produce 20 to 50 gallons per day.
Costs vary according to size.
Most manufacturers make only one or two basic distillation units. The differences between models are primarily the features or extra equipment. The same basic still may be sold as a portable, countertop or free-standing unit. Buyers should look closely to see if the differences are important to their situation. A good guide is the wattage of the units.