FIELD: power engineering; domestic and industrial water heaters. SUBSTANCE: water is heated in running-water electric heater first to intermediate temperature at its outlet, then water supply is interrupted, and water contained in its space is further heated within time interval required to attain desired temperature at water heater outlet; then water is passed through it for time interval within which temperature does not actually change; after that, mentioned operations are repeated within desired time period. EFFECT: reduced cost of water heater and reduced power requirement.
