FI20245835A1 - System and method of regulating sauna room temperature - Google Patents

Abstract

The invention relates to a system for regulating the temperature of a sauna room (8), which system comprises - a heater (10) arranged in the sauna room (8) for heating the sauna room (8) to a temperature of 60-120 °C, - a temperature sensor (40) for measuring the temperature of the sauna room (8), - control means for regulating the temperature of the sauna room (8) based on the measurement data of the temperature sensor (40), in which the heater (10) comprises - a frame (12), - a stone chamber (14) comprising a storage mass which is arranged to be heated to a temperature of 200-700 °C and which is arranged to vaporize water to be dispensed into the stone chamber (14), - a flow channel (20) in which the flowing fluid is arranged to be heated by the heat produced in the stone chamber (14), and - a valve (30) arranged to regulate the flow of the fluid in the flow channel (20). The system comprises thermostat means, with which the system is adapted to regulate the temperature of the sauna room (8) by regulating the opening degree of said valve (30) based on measurement data from a temperature sensor (40) measuring the temperature of the sauna room (8). The invention also relates to a corresponding method.

Description

SYSTEM AND METHOD FOR ADJUSTING THE TEMPERATURE OF A SAUNA ROOM

The invention relates to a system for regulating the temperature of a sauna room, which system comprises — a heater adapted to the sauna room for heating the sauna room to a temperature of 60-120 °C, — a temperature sensor for measuring the temperature of the sauna room, — control means for regulating the temperature of the sauna room based on the measurement data of the temperature sensor, in which the heater comprises - a frame, — a stone chamber comprising a storage mass adapted to be heated to a temperature of 200-700 °C and adapted to vaporize water dispensed into the stone chamber, — a flow channel in which the flowing fluid is adapted to be heated by the heat produced in the stone chamber, and — a valve adapted to regulate the flow of fluid in the flow channel.

The invention also relates to a corresponding method.

The so-called Finnish sauna heater consists of a stone chamber filled with heat-retaining stones or other mass, such as ceramics. The mass in the stone chamber is typically heated to a temperature of approximately 200-700 °C during use. In this case

In the S 25 operating situation, the water dispensed into the stone compartment of the heater evaporates

O quickly and creates steam, or steam, that rises and spreads from the stone space into the room, mainly upwards 2. The hot stone space of the sauna heater = also participates in heating the air in the sauna room, which > the air is typically heated to a temperature of about 60-120 °C & 30 mainly by convection. <

S

The problem with prior art sauna heaters is that when the sauna room reaches the target temperature, the heating power of the sauna heater has to be limited so that the temperature of the sauna room does not rise uncomfortably high, causing the mass in the stone space to cool down. Often, only the temperature of the sauna room acts as a factor controlling the heating, or more precisely, as a factor controlling the heating power of the sauna heater. In addition, the continuous dosing of water into the sauna stone space during sauna use can cool the sauna stones and the power of the sauna heater is not enough to maintain a sufficient temperature in the stone space if the temperature of the sauna room is at the target temperature. Once the temperature of the sauna room has stabilized and most of the sauna structures are at the target temperature, the heating power is no longer needed. In this case, the mass in the stone space is not heated or is heated minimally, even though users throw steam on the stones. In this case, the user feels that the sauna heater does not produce enough water vapor, i.e. steam.

Typically, the structure of the heater is designed to direct air through the stone space. Despite this, the air flow through the stone space is poor.

Furthermore, if the heater is used both to heat the air in the room and to create a hot stone space for the sauna, there is little possibility of adjusting the sauna intensity, as the temperature of the stone space directly affects both the sauna intensity and the room temperature. Therefore, the sauna intensity cannot be adjusted without affecting the

S 25 to room temperature.

S

2 Typically, for example, in an electric heater heated by resistors, the electric current fed to the resistors is controlled by thermostatic devices based on the measurement data of the temperature sensor measuring the temperature of the sauna room. Therefore, if

N the sauna room temperature is above the selected limit value and

If a lot of water is thrown into the stone space, the temperature of the stone space may drop too low for the sauna to produce steam, even if the temperature of the sauna room does not drop significantly. If the sauna

The room temperature does not drop, the thermostat does not order additional heating power for the heater.

The prior art includes heaters that comprise an adjustable flow channel, in which air is moved through the heater, thereby temporarily enhancing the transfer of heat to the sauna room. For example, patent publication FI101261B describes a so-called sauna-ready heater, which comprises a closing mechanism for a flow opening in the stone space connected to the lid, the opening of which causes rapid air passage through the hot stones into the surrounding sauna space. In this way, the main aim is to speed up the heating of the sauna room at the beginning of heating.

However, state-of-the-art sauna heaters cannot control the temperature of the sauna room and stone space in the desired way, nor can they improve or adjust the user's sauna experience.

The purpose of the invention is to provide an improved system and method for controlling the temperature of a sauna room, with which the temperatures of the stone space and the sauna room can be controlled more versatilely than before and thus enable a better sauna experience.

The characteristic features of the heater according to the invention are set out in the accompanying patent claim 1 and the characteristic features of the method are set out in patent claim 13.

S 25

O The system according to the invention for adjusting the temperature of a sauna room comprises a heater adapted to the sauna room for heating the sauna room to a temperature of 60—120 °C, a temperature sensor for measuring the temperature of the sauna room, control means for adjusting the temperature of the sauna room and the measurement data of the temperature sensor.

Based on N, in which system the heater comprises a frame,

N a flow channel of a stone chamber comprising a storage mass adapted to be heated to a temperature of 200-700 °C and adapted to vaporize water dispensed into the stone chamber,

wherein the flowing fluid is adapted to be heated by the heat produced in the stone space, and the valve is adapted to regulate the flow of the fluid in the flow channel. The system comprises thermostat means, with which the system is adapted to regulate the temperature of the sauna room by regulating the opening degree of said valve based on the measurement data of a temperature sensor measuring the temperature of the sauna room.

In other words, the system according to the invention regulates the temperature of the sauna room by regulating the amount of air flowing through the flow channel and/or the stone space, and thus regulates the amount of power transferred from the stone space to the sauna room. The aim of the heater itself is to keep the heater stones in a steaming condition at all times during sauna use, i.e. to keep the temperature of the stone space at a selected level. The temperature of the sauna room is measured by a temperature sensor, which can be placed anywhere in the sauna room or can also be attached to the heater. It is not essential to measure the absolute temperature of the sauna room, but the temperature sensor measures any temperature that is dependent on the temperature of the sauna room and/or indicates the temperature of the sauna room.

In this way, the temperature of the sauna room can be adjusted by adjusting the valve position with thermostatic devices. If more heat is needed in the sauna room, the flow channel flowing through the heater, which can be formed by a stone space or a separate one, is opened.

S 25 penetrating/adjacent pipe, allowing heat to be transferred from the stones

O to the sauna room. If the sauna room is warm enough, the 2 flow channel is closed, allowing the temperature of the stone room to be better controlled and the selected temperature level to be maintained in the stone room. > The control devices maintain the temperature of the sauna room at the selected level during the sauna session & 30. In this way, the temperature of the stone room is

N is better controlled than before and especially the temperature of the stone space

N can be kept sufficiently high even when the sauna room temperature is at the target level.

In this way, the sauna temperatures can be controlled more flexibly than before, both in the sauna room and in the stone room. In particular, the stone room can be kept at the selected temperature during sauna use to create an effective steam effect. 5

The valve here means that complete air tightness is not required, but the valve restricts the flow of fluid by at least 90% in the closed position compared to the open position. The valve can be controlled between closed and open positions or in addition to these there can also be one or more partially open positions for fine adjustment. The valve can be located in any part of the flow channel. The fluid can be air or water vapor.

Thanks to the adjustable valve according to the invention, the stone space can also be insulated better than before without adversely affecting the sauna output of the heater. In other words, when the air flow is actively controlled with the valve, the stone space can be insulated better and thus heat can be stored in the stone space better than before.

When the valve is closed, the air flow through the stone space of the heater is reduced, which means that the heat is better stored in the mass in the stone space. < Preferably, the system comprises a stone space temperature in the heater

S 25 measuring J temperature sensor and the system is adapted

O thermostatic means to adjust the temperature of the stone room based on the measurement data of the temperature sensor measuring the temperature of the stone room 2. In this way, the temperature of the stone room is measured by the temperature sensor and can be adjusted by the thermostatic means. & 30 The temperature of the stone room can therefore be maintained during sauna bathing

N at the selected level more precisely than before. The temperature of the stone space

N can also be adjusted more precisely than before, in the way the user wishes, which can affect the intensity of the sauna.

For example, the user can input the desired temperature of the stone space to the control means, whereby the temperature of the stone space is maintained at this desired temperature within the selected tolerance.

When the temperature sensor measuring the temperature of the stone space detects that the stone space has cooled below a selected limit value during sauna bathing, the control means can be adapted to order additional heating power to heat the mass in the stone space based on the reading of the temperature sensor measuring the temperature of the stone space.

Thermostatic means here broadly refers to any means that automatically regulates the temperature, which may be, for example, a means that regulates the degree of opening of a valve or a means that controls the heating power of the stone space. The system may comprise several thermostatic means, for example, so that the first thermostatic means are adapted to regulate the temperature of the sauna room by regulating the degree of opening of the valve and the second thermostatic means are adapted to regulate the temperature of the stone space by regulating the heating power, such as the power of the electric current supplied to the resistors.

Correspondingly, control means are broadly understood here to mean any means used to regulate the temperature of the sauna room, by which the control command formed on the basis of the temperature sensor reading is transmitted to the thermostat means. < Control means may comprise electronic and/or mechanical

S 25 components. The control means may consist of, for example,

O the sauna's electronic control unit and the software it comprises, which is adapted to read one or more temperature sensors and to control the degree of opening of the valve and/or the heating power supplied to the heater using thermostatic means. The control means can also be mechanical, for example

N component that transmits the temperature sensor reading

Based on N, a control command is issued to the thermostatic devices that control the valve or that control the supply of fuel to be burned in the heater based on the temperature sensor reading.

The stone space of the heater can be partially closed so that the heater body can cover at least 50%, preferably at least 80%, of the stone space. In other words, at most 50%, preferably at most 20%, of the area of the edges of the stone space is then visible from the outside of the heater. In this way, the desired temperature in the stone space can be maintained more easily.

The heater may also comprise a lid over the stone space, in which an opening of a selected size is arranged for dispensing water.

This allows heat to be stored better in the stone space during use, allowing better control of the temperature of the stone space. The stone space may also be thermally insulated and include a lid that is closed when the sauna is not in use to store heat in the stone space.

In one embodiment, the stone space of the stove is adapted to be heated by resistors, and the thermostat means are adapted to adjust the power of the electric current supplied to the resistors. In this way, the desired temperature can be produced in the stone space by electrical energy.

The resistors can be arranged in the stone space or outside the stone space. < In another embodiment, the stone space of the heater is arranged

S 25 for heating by burning wood or gas or combustible

O fluid, such as oil, or by friction generated by an electrically driven turbine. In this alternative way, the desired temperature can be produced in the stone space by burning organic 2 . matter. 10

N In other words, in the system according to the invention, it is possible to

N uses any state-of-the-art heat generation equipment and energy source to heat the sauna room and stone room.

In this case, the stove may comprise a firebox and the system may comprise means for regulating the flow of inlet air to the firebox.

In this way, the combustion power and thus the temperature of the stone chamber can be adjusted.

The heater may also comprise means for controlling the supply of gaseous or liquid combustible material. In this way, the heating power of the heater can be adjusted in an alternative manner.

In this case, the kiln may comprise a flue duct and a flue gas temperature sensor, and the system comprises an adjustable throttle in the flue duct for adjusting the combustion output by throttling the flue duct based on the measurement data of the flue gas temperature sensor. In this way, the combustion output and thus the temperature of the kiln space can be adjusted in an alternative manner.

Throttling of the inlet air and/or smoke duct can be used in one embodiment or in separate embodiments.

In one embodiment, the system comprises an electronic actuator, such as a solenoid or servomotor, for controlling the degree of opening of the valve. In this way, the degree of opening of the valve can be precisely controlled using electrical energy.

S 25

In another embodiment, the system comprises a thermo-mechanical actuator, such as a capillary thermostat or a bimetallic thermostat, for adjusting the valve opening degree. In this way, the valve opening degree can be adjusted without electricity and it is possible to construct the system completely electrically-

X is empty.

In one embodiment, the flow channel of the heater is formed by an opening in the lower part of the heater body, to which a valve is fitted,

and the stone space. In this way, a flow channel can be formed in the heater in a simple way, where the flowing fluid can be heated by the heat produced in the stone space.

In another embodiment, the flow channel of the heater is a closed tube having a first opening for air inlet and a second opening for air outlet, and the first opening is located at the bottom of the heater, and the second opening is outside the stone space, vertically above the stone space.

In this way, the flow of fluid flowing through the heater can be precisely controlled and the fluid discharged from the flow channel can be delivered to the desired location.

Alternatively, the other mouth of the pipe can also be inside the stone space.

In a third embodiment, the flow channel of the heater is a closed tube with a first opening for air inlet and a second opening for air outlet, and the first opening is located in the lower part of the heater, and the second opening is located outside the stone space in the height direction below the center line of the stone space. In this way, warm air can be produced in the lower part of the sauna room, whereby temperature differences can be equalized in the sauna room, where the air in the upper part is typically in use.

S 25 significantly warmer than the air in the lower part. 3 x Preferably in the third embodiment described above, the pipe = runs between the first mouth opening and the second mouth opening above the stone space >. In this way, natural convection is achieved, & 30 whereby air is made to flow in the pipe.

The pipe described above can also be used without the valve described above. In this case, the pipe can be used to direct the flow of warm fluid flowing out of the heater to a desired location in the sauna room.

Preferably, there is a radiation shield between the part of the pipe outside the stone space and the stone space. In this way, the heat from the heater can be prevented from radiating into the pipe, thereby ensuring that the air flow in the pipe is not disturbed. The radiation shield can be a separate component or part of the heater body.

In the method according to the invention, a heater is used to heat the sauna room, which heater comprises a frame, a stone space comprising a storage mass and into which water is dosed for evaporation, a flow channel in which the flowing fluid is heated by the heat produced in the stone space, and a valve with which the flow of fluid in the flow channel is regulated, the sauna room is heated to a temperature of 60-120 °C, the stone space is heated to a temperature of 200-700 °C, the temperature of the sauna room is measured with a temperature sensor, the temperature of the sauna room is regulated based on the measurement data of the temperature sensor. In the method, the temperature of the sauna room is regulated by thermostatic means by adjusting the opening degree of the valve based on the measurement data of the temperature sensor measuring the temperature of the sauna room. x < 25 In this way, the temperatures of the sauna can be controlled more than before

O more versatile in terms of both the sauna room and the stone room temperatures 2. In particular, the stone room can be maintained during sauna use

E at the selected temperature to create an effective sauna effect. 3 8 30 Preferably, the temperature of the stone space is measured with a temperature sensor and

N The heating of the stone room is regulated by thermostatic devices in the stone room.

Based on the measurement data from the temperature sensor measuring the temperature N. In this way, the temperature of the stone room can also be adjusted more precisely than before in the way the user wishes, which can affect the intensity of the sauna.

Preferably, the method sets a first limit value and a second limit value for the temperature of the sauna room, of which the first limit value is lower than the second limit value, and when the temperature of the sauna room is below the selected first limit value, the stone space is heated and the valve is opened, when the temperature of the sauna room is above the selected first limit value and below the selected second limit value, the stone space is heated and the valve is closed, and when the temperature of the sauna room is above the selected second limit value, the heating of the stone space is limited and the valve is closed. In this way, in the selected first stage, the transfer of heat produced in the stone space to the air in the sauna room can be enhanced, and on the other hand, in the selected second stage, the transfer of heat produced in the stone space to the air in the sauna room can be reduced, whereby the heat can be stored in the stone space to achieve an effective steam effect, but the air temperature in the sauna room can be maintained at a comfortable level for the user.

The invention is described in detail below with reference to the accompanying drawings illustrating some embodiments of the invention, x in which

S 25

O Figure 1 shows a system according to the invention, 2 Figure 2 shows a system according to the invention = a heater in a situation where the valve is closed, > Figure 3 shows a heater according to the invention & 30 in a situation where the valve is opened,

N Figure 4 shows a system according to another invention.

System heater,

Figure 5 shows a heater of a third system according to the invention.

Figure 1 shows a system according to the invention for regulating the temperature of a sauna room 8, which system comprises a heater 10 arranged in the sauna room 8 for heating the sauna room 8 to a temperature of 60-120 *C, a temperature sensor 40 for measuring the temperature of the sauna room 8, control means for regulating the temperature of the sauna room 8 based on the measurement data of the temperature sensor 40, in which the heater 10 comprises a frame 12, a stone space 14 comprising a storage mass which is arranged to be heated to a temperature of 200-700 *C and which is arranged to vaporize water to be dispensed into the stone space 14, a flow channel 20 in which the flowing fluid is arranged to be heated by the heat produced in the stone space 14, and a valve 30 arranged to regulate the flow of the fluid in the flow channel 20. The system comprises thermostat means with which the system is arranged to regulate the temperature of the sauna room 8 by regulating the valve 30 degrees of opening based on the measurement data of the temperature sensor 40 measuring the temperature of the sauna room 8.

The stone space 14 is here adapted to be heated by resistors 16.

The stone space 14 is here partially closed so that the body 12 of the heater 10 covers more than 50% of the stone space 14. The stone space 14 here comprises stones 15 as a heat-storing mass. The cross-section of the heater < 10 shown in the figures is a principle and the body 12 does not need to be

S 25 should not be continuous around the stone space 14, but the frame 12 can comprise

In addition to the flow channel 20, there are also other openings from which air can flow through the stone space 14. The heater 10 can also be a so-called = cage heater, in which the body of the heater is formed at least partially from a metal mesh.

O 30 10

N The position of the valve 30 is controlled by a motor 34, which operates here

N as a thermostatic means. Motor 34 is herein a generic term for any electronic or mechanical actuator that can be used to change the degree of opening of valve 30. Motor 34 may be, for example, an electric motor, such as a servo motor, or a solenoid valve may be used. Motor 34 and valve 30 are connected to the control means of the system.

The motor 34 may alternatively be a thermomechanical component, which will be discussed in more detail later.

The heater 10 belonging to the system of Figure 1 is shown in more detail in Figures 2 and 3, with the help of which the operation of the system is explained in more detail.

The temperature of the sauna room 8 is monitored by a temperature sensor 40, which is fitted to the upper part of the wall of the sauna room 8. The temperature sensor 40 can alternatively also be fitted to the ceiling of the sauna room 8 or, for example, integrated into the heater 10. The measurement data of the temperature sensor 40 is supplied to the control means, which are here placed in the system control unit 60. The control means is here an electronic component, which, based on the measurement data of the temperature sensor 40, controls the opening degree of the valve 30 of the heater 10. For example, when the temperature of the sauna room 8 is below the selected first limit value, the valve is opened completely, and when the temperature of the sauna room 8 is above the selected first limit value, the valve 30 is closed completely. Between the fully opened and fully closed positions <, fine adjustment can also be used, in which the valve 30 is partially

S 25 open.

S x The temperature of the stone room 14 is monitored here with a separate temperature sensor 18. The measurement data of the temperature sensor 18 is supplied to the control means, which, based on the measurement data of the temperature sensor 18 & 30, control the heating of the stone room 14, i.e. in this case to the resistors

N 16 the power of the supplied electric current. For example, the stone room 14

When the temperature of N is below the selected limit value, 100% of the system capacity is supplied to the resistors 16, and when the temperature of the stone space 14 is above the selected limit value, the resistors

16 0% power is supplied. Instead of 100% and 0% power supplies, fine adjustment can also be used, in which the supplied power is between 0% and 100% in the selected situation.

With the control means, the user can advantageously adjust the control of the system to automatically maintain a first selected temperature for the air in the sauna room 8 and a second selected temperature for the stone space 14.

To ensure the safety of the sauna, the system can also be programmed to limit the heating of the stone space 14 if the air temperature in the sauna room 8 rises above the selected second limit value. In other words, if closing the valve 30 is not enough to keep the temperature in the sauna room 8 at the selected level, the heating of the stone space 14 is also switched off or reduced to partial power.

In this embodiment, the flow channel 20 of the heater 10 consists of an opening 25 in the lower part of the body 12 of the heater 10, in which the valve 30 is fitted, and a stone space 14.

In the situation in Figure 2, valve 30 is closed and closes opening 25.

In this case, the air flow through the stone space 14 is very low and the heat transfer from the stone space 14 to the air in the sauna room 8 is very low.

S 25 convection is thus negligible.

S

2 In the situation of Figure 3, the valve 30 and the opening 25 are fully open. = In this case, air 42 can flow from the outside of the body 12 of the heater 10 through the opening 25 into the flow channel 20 and the stone space 14 and & 30 through the stone space 14. Heat is transferred from the stone space 14 through the stone space 14

N to the flowing air 42, which exits from the top of the heater 10. Thus

The air 42 flowing through the N flow channel 20 effectively heats the air in the sauna room 8 by convection.

Figure 4 shows another embodiment of the system heater 10, in which the flow channel 20 of the heater 10 is formed by a closed tube 50, which has a first opening 51 for air inlet and a second opening 52 for air outlet, and the first opening 51 is placed in the lower part of the heater 10, and the second opening 52 is outside the stone space 14 in the height direction above the stone space 14. In this way, cool air can be sucked from the lower part of the sauna room 8 into the first opening 51 of the tube 50.

The pipe 50 is here adapted to pass through the stone space 14.

Alternatively, the pipe 50 or another alternative flow channel 20 may be located, for example, next to the stone space 14, however, so that the heat produced in the stone space 14 is transferred to the air flowing in the flow channel 20. As it passes through the pipe 50, the air 42 heats up and the heated air is discharged from the second opening 52 of the pipe in a controlled manner to a selected location in the sauna room 8.

Figure 5 shows a third embodiment of the system heater 10, in which the flow channel 20 of the heater 10 is a closed tube 50 having a first opening 51 for air inlet and a second opening 52 for air outlet, and the first opening 51 is located in the lower part of the heater 10, and the second opening 52 is outside the stone space 14 in the height direction below the centerline of the stone space 14. In this embodiment, < the warm air discharged from the second opening 52 of the flow channel 20

S 25 air 42 is delivered to the lower part of the sauna room 8, which allows

O to equalize the temperature differences in the height of the sauna room 8. In this 2 embodiment, there is a radiation shield 56 between the part of the flow channel 20 outside the stone space 14 and the stone space 14, which can be a metal plate, for example. 3 30

N In a fourth embodiment according to the invention

The stone chamber 14 of the N system stove 10 is adapted to be heated by burning wood or gas or a flammable liquid, such as oil.

In this case, the stove 10 comprises a firebox and the system comprises means for regulating the flow of inlet air to the firebox. These means may be any means according to the state of the art, such as a manual or electrical control device with which the cross-sectional area of the inlet air duct can be regulated. The stove 10 may also in this case comprise means for controlling the supply of the material to be burned.

Alternatively or additionally, the stove 10 comprises a flue and a flue gas temperature sensor, and the system comprises an adjustable throttle in the flue for adjusting the combustion output by throttling the flue based on the measurement data of the flue gas temperature sensor. The throttle may be any throttle according to the state of the art, such as a manual or electrical control device with which the cross-sectional area of the flue can be adjusted.

At its simplest, a damper is a movable metal plate in a smoke duct.

The system does not have to be fully automated, but for example the means for regulating the flow of incoming air to the firebox and/or the flue gas damper can be manual components that the user adjusts manually to achieve the desired temperature of the stone space and thus the desired sauna effect. Preferably, however, the heating of the stone space 14 is

S 25 automated, allowing the temperature of the stone room 14 to be maintained

O at the desired level during the sauna session without user intervention. 2 = Preferably, the heating of the sauna room 8 is automated, whereby > the temperature of the sauna room 8 can be kept at the desired level & 30 during the sauna session without user intervention. Motor 34

N can be used to adjust the opening position of valve 30

Regardless of the heating method of the stone room 14, alternatively a thermomechanical actuator, such as a capillary thermostat or a bimetallic thermostat, is used to adjust the opening degree of the valve 30. In this case, the valve 30 is hinged and the thermomechanical actuator is adapted to apply mechanical work to the valve 30 according to the change in temperature of the sauna room 8, which adjusts the opening degree of the valve 30. The thermomechanical actuator can be, for example, a ''solid fuel thermostat'' manufactured by Rathgeber GmbH. <t

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Claims (15)

PATENT CLAIMS 1. A system for regulating the temperature of a sauna room (8), the system comprising — a heater (10) adapted to the sauna room (8) for heating the sauna room (8) to a temperature of 60-120 °C, — a temperature sensor (40) for measuring the temperature of the sauna room (8), — control means for regulating the temperature of the sauna room (8) based on the measurement data of the temperature sensor (40), in which the heater (10) comprises = a frame (12), - a stone space (14) comprising a storage mass adapted to be heated to a temperature of 200-700 °C and adapted to vaporize water to be dispensed into the stone space (14), — a flow channel (20) in which the flowing fluid is adapted to be heated by the heat produced in the stone space (14), and — a valve (30) adapted to regulate the flow of the fluid in the flow channel (20), characterized in that — the system comprises thermostat means with which the system is adapted to adjust the temperature of the sauna room (8) by adjusting the opening degree of said valve (30) based on the measurement data S 25 of the ld&mpdtila sensor (40) measuring the temperature of the sauna room (8). S 2 2. A system according to claim 1, characterized in that the system comprises a temperature sensor (18) measuring the temperature of the stone space (14) in the heater (10) and the system is & 30 adapted to adjust the temperature of the stone space (14) N by thermostat means based on the measurement data of the temperature sensor N (18) measuring the temperature of the stone space (14). 3. A system according to claim 1 or 2, characterized in that the stone space (14) of the heater (10) is partially closed so that the body (12) of the heater (10) covers at least 50%, preferably at least 80%, of the stone space (14). 4. A system according to any one of claims 1-3, characterized in that the stone space (14) of the heater (10) is adapted to be heated by resistors (16), and the thermostat means are adapted to adjust the power of the electric current supplied to the resistors (16). 5. A system according to any one of claims 1 to 3, characterized in that the stone space (14) of the stove (10) is adapted to be heated by burning wood or gas or a combustible liquid, such as oil, or by friction generated by an electrically driven turbine. 6. A system according to claim 5, characterized in that the heater (10) comprises a firebox and the system comprises means for regulating the flow of inlet air to the firebox. 7. A system according to claim 5 or 6, characterized in that the heater (10) comprises a smoke channel and a flue gas temperature sensor, and the system comprises an adjustable throttle in the smoke channel for adjusting the combustion power by throttling the smoke channel based on the measurement data of the flue gas temperature sensor. 7 LO 8. A system according to any one of claims 1 to 7, characterized in that the system comprises an electronic actuator, such as a solenoid or servomotor, for adjusting the degree of opening of the valve (30). 9. A system according to any one of claims 1 to 8, characterized in that the system comprises a thermomechanical actuator, such as a capillary thermostat or a bimetallic thermostat, for adjusting the degree of opening of the valve (30). 10. A system according to any one of claims 1 to 9, characterized in that the flow channel (20) of the heater (10) consists of an opening in the lower part of the body (12) of the heater (10), in which the valve (30) is fitted, and a stone space (14). 11. A heater (10) according to any one of claims 1 to 8, characterized in that the flow channel (20) of the heater (10) is a closed tube (50) having a first opening (51) for air inlet and a second opening (52) for air outlet, and the first opening (51) is located in the lower part of the heater (10), and the second opening (52) is located outside the stone space (14) in the height direction above the stone space (14). 12. A heater (10) according to any one of claims 1 to 8, characterized in that the flow channel (20) of the heater (10) is a closed tube (50) having a first opening (51) for air inlet and a second opening (52) for air outlet, and the first opening (51) is located in the lower part of the heater (10), < and the second opening (52) is outside the stone space (14) in the height direction below the center line of the stone space (14). S 2 13. A method for regulating the temperature of a sauna room (8), = in which method > — a heater (10) is used to heat the sauna room (8), & 30 each heater (10) comprises a frame (12), a stone chamber (14) which comprises a storage mass and into which water is dosed for evaporation, a flow channel (20) in which the flowing fluid is heated by the heat produced in the stone chamber (14), and a valve (30), with which valve (30) the fluid flow in the flow channel (20) is regulated, — the sauna room (8) is heated to a temperature of 60—120 °C, — the stone space (14) is heated to a temperature of 200—700 °C, — the temperature of the sauna room (8) is measured by a temperature sensor (40), — the temperature of the sauna room (8) is regulated on the basis of the measurement data of the temperature sensor (40), characterized in that — the temperature of the sauna room (8) is regulated by thermostatic means by adjusting the opening degree of said valve (30) on the basis of the measurement data of the temperature sensor (40) measuring the temperature of the sauna room (8). 14. A method according to claim 13, characterized in that the temperature of the stone space (14) is measured by a temperature sensor (18) and the heating of the stone space (14) is adjusted by thermostat means based on the measurement data of the temperature sensor (18) measuring the temperature of the stone space (14). 15. A method according to claim 13 or 14, characterized in that a first limit value and a second limit value are set for the temperature of the sauna room (8), the first limit value being lower than the second limit value, and < — when the temperature of the sauna room (8) is below the selected first limit value S 25, the stone space (14) is heated and said O valve (30) is opened, 2 — when the temperature of the sauna room (8) is above the selected first limit value E and below the selected second limit value, LO the stone space (14) is heated and said valve (30) is closed, 3 30 and N — when the temperature of the sauna room (8) is above the selected second limit value N, the heating of the stone space (14) is limited and said valve (30) is closed.