Abstract: A boiler, including: electrodes immersed in contained water, for heating thereof; and a separating circuit, for supplying electric power from an electric grid supply to the electrodes therethrough in an electric separated manner, thereby the water electrified by the electrodes is electrically separated from the electric grid supply, thereby providing safety.

Abstract: A boiler, including: electrodes immersed in contained water, for heating thereof; and a separating circuit, for supplying electric power from an electric grid supply to the electrodes therethrough in an electric separated manner, thereby the water electrified by the electrodes is electrically separated from the electric grid supply, thereby providing safety.

Abstract: There is disclosed an inflatable hole sealing device including an inflatable sheet insertable in a hole and suitable to wrap a section of an interconnection means, and an inflation mechanism to introduce an expanding material into the sheet. There is additionally disclosed a kit including the inflatable hole sealing device and an inflator device attachable to the inflation mechanism for administering the expanding material.

Abstract: In one aspect, the present invention is directed to a heating device comprising: a heating container (10, 12); an inlet (40, 72), through which water to be heated enters the heating container (10, 12), the inlet being disposed at a lower portion of the container (10,12); a first outlet (62, 74), through which water heated within the heating container (10,12) exits thereof, the first outlet drawing water from a high portion of the container (10, 12); and a second outlet (44, 22) for drawing water from a low portion of the container (10, 12), the second outlet being openable for releasing therethrough water including accumulated scale, thereby enabling discarding scale when accumulated in the container (10, 12).