A system includes: a heat generator obtaining heat from a heat source and having a generator outlet port and a generator return port; a central heating circuit having a heating feed port and a heating return port; a tank having a top portion and a bottom portion, the tank containing a heat storing medium; a first tapping coil immersed in the heat storing medium in the bottom portion of the tank; and a second tapping coil immersed in the heat storing medium in the top portion of the tank The heat generator, second tapping coil, central heating circuit, and first tapping coil are fluidly connected in series to allow fluid to flow from the heat generator via at least one of the second tapping coil, the central heating circuit, and the first tapping coil back to the heat generator The system includes first, second and third three-way valves.

The present disclosure relates to a boiler for making hot water and room heating water available simultaneously, which is capable of enabling a user to use hot water and room heating simultaneously. According to the present disclosure, a thermal loss of room heating water may be minimized because the room heating water is independently supplied to a room heating pipe and returned regardless of the use of hot water, and the hot water with a high temperature may be consistently supplied because the hot water is independently supplied to a hot water pipe and returned regardless of the use of the room heating water. In addition, the boiler may serve as both a hot-water heat exchanger and a distributor (low loss header).