To improve efficiency in reproduction, and to easily miniaturize a constitution of a device.
This water heater includes a hot water storage tank 24, a water heating means 26, and a water softening means 27. The water softening means 27 is composed of a bipolar charged membrane 32 having at least a pair of two layers of a cation exchanging layer 34 and an anion exchanging layer 35 disposed in opposition to each other through a flow channel 33, and a pair of electrodes 31 disposed through the bipolar charged membrane 32. A hard component is removed by the bipolar charged membrane by introducing water softened by the water softening means 27 to the water heating means 26, and the attachment of a scale in equipment can be prevented. Furthermore, since an area of an interface between the cation exchanging layer and the anion exchanging layer is large and the disassociation of water can be efficiently performed at a low voltage by applying voltages from both sides of the bipolar charged membrane, regeneration can be performed with low power consumption.
OKETA TAKEMI
YASUI KEIKO
HORIKI YASUSUKE
Hiroki Naito
Daisuke Nagano