Double wall vacuum-insulated keeps water hot while saving energy and money.

双层真空隔热保持热水，同时节省能源和金钱。

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A solar water heater system is composed of vacuum solar energy absorber, electrically aided heater and water-saving antifreezing unit.

一种太阳能热水器系统装置，它由真空太阳能吸收器、电辅助加热装置、节水防冻装置构成。

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