Most dispensers get the water supply from a water bottle and work by heating or cooling the water as it is dispensed. The system stores water in the reservoir and uses electric heating elements to warm the water while using an A/C unit to cool down the temperature. You can keep your drinks at the desired temperature without waiting. Many dispensers also have an indicator light that lets you know when the water is ready to use. All in all, the dispensers are perfect for busy households who want quick and convenient access to icy drinks on hot days or thirst-quenching liquids on chilly evenings!