Warm water heater without producing water scales

The invention discloses a warm water heater without producing water scales, belongs to the technical field of electric heating devices, and in particular relates to the warm water heater without producing the water scales. The invention provides the warm water heater which is simple in structure, capable of lowering the whole surface temperature of a heating rod and not producing the water scales and being low in requirement for water pressure. The warm water heater comprises the heating rod and is characterized in that the heating rod is externally provided with a sleeve, one end of the sleeve is close, the other end of the sleeve is open, the closed end of the sleeve is provided with a water inlet, the inner wall of the sleeve is provided with oriented spirochetes, and a gap is arranged between the oriented spirochetes and the heating rod.