Electric water heaters have the advantages of long lifespan, high efficiency, energy conservation, safety, and environmental protection. They can also be hidden in wall cabinets and balconies, without being exposed or occupying land. Instant electric water heaters have relatively high power and high circuit requirements: generally, the power is required to be at least 6KW or above, and even 8KW in winter is difficult to ensure sufficient hot water for bathing. The power cord requires at least 2.5 square meters or more, and some require 5 square meters or more.

Although the volume of an ordinary fast heating electric water heater is similar to that of a dual mode electric water heater, the internal structure is vastly different. Compared to a water storage electric water heater, a fast heating electric water heater is only smaller in size and has higher power, so it is indeed faster in heating speed than a water storage electric water heater. However, it cannot achieve instant heating in spring and autumn and needs to be preheated, which requires waiting. However, a dual mode electric water heater can only achieve instant heating in spring and summer The instant heating mode is available for the three seasons of autumn, which is instant heating.