The object of this invention is an apparatus, which we call the sauna oven center boiler, intended as a solution for heating houses and properties. This invention belongs to the field of heating and water technology.

The known solutions, i.e., heating stoves, in this field of technology are the center boiler and the sauna stove, i.e., sauna oven. Those are separate units, which both require their own space and ventilation-ducts, thereby increasing construction costs.

The purpose of the invention is to decrease construction costs and emissions as well as, on the other hand, to free property space for other use.

According to this invention, this purpose can be attained by integrating the sauna oven and the center boiler. It is functional to locate this invention in the sauna space of the house or other property. There are several advantages in using a sauna oven central boiler according to the invention. When heating a property with one furnace, water supply as well as the sauna becomes warm at the same time. Because the diameters of the incoming and outgoing water pipes connected to the space where water is being heated are large enough, preferably pipes with 70 - 90 mm diameter, the sauna oven center boiler operates with gravity flow. Because of the gravity flow solution, the sauna oven center boiler also operates during power failures. Only one ventilation duct is required for the sauna oven center boiler, and as the sauna oven center boiler is located in the sauna, no separate boiler room is re- quired. By extending the incoming and outgoing water pipes running between the sauna oven center boiler and hot water boiler through the wall structure between those spaces, the hot water boiler can be located in a room adjacent to the sauna. As a heating system using solid fuel, preferably wood, the output of the sauna oven center boiler is high, but its external dimensions are relatively small.

Characteristic to the sauna oven center boiler according to the invention is the arrangement of the sauna oven and the center boiler into an integrated apparatus so that, when the resulting sauna oven center boiler is connected to the hot water boiler with incoming and outgoing water pipes, by burning just one fur- nace, it is possible to warm the heating water, water supply, and the sauna oven of a house and other property. The upper part of the sauna oven center boiler comprises a traditional sauna oven, i.e., a sauna stone heater part, and the lower part of sauna oven center boiler, i.e., the kettle part, comprises a furnace, a space for ash collection, and a space i.e., a tank, for water heating as well as combustion flues for conducting smoke from the furnace into a ventilation duct. Part of the combustion flue also belongs to the sauna stone heater part, against which also the space for heating the water extends. A characteristic location for the sauna oven center boiler in a house or other property is its sauna facility.

The following is a description of this inven- tion in more detail by referring to the appended drawings, where Figure 1 presents a cross-sectional drawing of the sauna oven center boiler from the front,

Figure 2 presents the cross-sectional drawing of the sauna oven center boiler from the side, Figure 3 presents a front view of the sauna oven center boiler,

Figure 4 presents a top view of the sauna oven center boiler,

Figure 5 presents a cross-sectional drawing of the sauna oven center boiler's ventilation duct connection,

Figure 6 presents a cross-sectional drawing of the sauna stone heater part of the sauna oven center boiler, and Figure 7 presents the connection between the sauna oven center boiler and the hot water boiler.

The sauna stone heater part 26 of the sauna oven center boiler 1 contains a sauna stone heater cover 2, cooling openings 17, a steam door 3, sauna oven stones 15, an ash sweeping door 24, and combustion flues 14, which combustion flues 14, running alongside the sauna oven stones 15, also belong to the kettle part 27 of the sauna oven center boiler 1. The kettle 27 of the sauna oven center boiler 1 also includes a furnace 20, equipped with a door 10, an air intake opening 12, and an ash dump, i.e., a hearth 21, and a combustion flue 19, equipped with an ash sweeping door 9, running from there through or alongside the water space 18 into a combustion flue 14, equipped with a ventilation duct connection 5, below the sauna oven stones 15. An ash pit door 11 and a pull-out ash box 22 belong under the furnace 20. The sauna oven center boi- ler also contains fire wool 16 included in its housing as heat insulation, a thermometer 13, a pressure control valve 4 for discharging overpressure, hot water boiler connection parts for the outgoing water pipe 6 and incoming water pipe 7 as well as a valve 8 for emptying the kettle.

An alternative modification is a so-called swinging damper system mounted onto the sauna oven center boiler 1, with which, as desired, the sauna stone heater part 26 of the sauna oven center boiler 1 may be essentially left unheated by directing the smoke gases not to flow through the combustion flue 14 on the swinging damper 23 between the combustion flues 19 and 14. According to another alternative modification, circulation pumps can be connected to the sauna oven center boiler 1 and electrical resistors to the hot water boiler 25.