NOVELTY - The device comprises a cuboid-shaped container filled with a latent heat storage material of a salt hydrate whose latent heat in a phase transition is stored in a solid/liquid medium, where walls of the container are constructed in multilayers. An inner layer made from an isotropic heat conducting graphite plate (2) is connected with the heat storage material. Outer surfaces of the graphite plates are closely covered by a liquid tight stable elastomer film (3) chemically against the latent heat storage material. Non-ferrous metal plates (4) are arranged in contact with the elastomer film.    USE - The device is useful for storing latent and sensitive heat (claimed) in buildings for heating water and for heating purposes.    ADVANTAGE - The device allows effective and economical storage of the latent and sensitive heat in buildings, and exhibits high corrosion resistant and prolonged service life.    DETAILED DESCRIPTION - The device comprises a cuboid-shaped container filled with a latent heat storage material of a salt hydrate whose latent heat in a phase transition is stored in a solid/liquid medium, where walls of the container are constructed in multilayers. An inner layer made from an isotropic heat conducting graphite plate (2) is connected with the heat storage material. Outer surfaces of the graphite plates are closely covered by a liquid tight stable elastomer film (3) chemically against the latent heat storage material. Non-ferrous metal plates (4) are arranged in contact with the elastomer film, and partially comprise flow channels. The plates are arranged with the flow channels so that a flow of a liquid transporting the heat passes through an inner part of the container. The flow channels of the plates open in collection and manifold blocks, which comprise terminals for flow and return flow pipes. The non-ferrous metal plates are tightly, completely covered by thermal insulation plates (5). The collection and manifold blocks are equipped with directional valves.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a latent heat storage.    Graphite plate (2)    Elastomer film (3)    Non-ferrous metal plates (4)    Thermal insulation plates (5)    Collection and manifold blocks. (6)