WO1998030843A1

WO1998030843A1 - Thermal storage heating stove for a central heating system

Info

Publication number: WO1998030843A1
Application number: PCT/CH1997/000476
Authority: WO
Inventors: Franz Pfrunder
Original assignee: Franz Pfrunder
Priority date: 1997-01-06
Filing date: 1997-12-22
Publication date: 1998-07-16
Also published as: AU7995098A

Abstract

A thermal storage heating stove (1) is placed in front of a wall or in a corner of a room leaving a gap between the walls of the room and the adjacent walls of the stove. A heat exchanger (5) is arranged in each gap. Each heat exchanger (5) consists of a copper pipe with windings. It is subdivided into long straight sections and into short sections bent through 180 DEG . The two end sections (9) of the heat exchanger (5) are located next to each other, making it easier to connect the heat exchanger to a supply network (10). The heat exchanger (5) can be connected to the supply network (10) of an existing central heating system or to a supply network (10) especially installed for the thermal storage heating stove.

Description

Storage heater for central heating

The invention relates to a storage heater for central heating according to the preamble of patent claim 1.

With the help of heating systems, rooms in buildings are warmed to create a physiologically favorable environment. A basic distinction can be made between individual heaters and central heating systems. Individual heaters only heat up the room in which they are located. They can be designed as open or closed fireplaces or as electrical resistance heaters. The closed fireplaces include the permanent fire stoves and the storage stoves, e.g. Tiled stoves or soapstone stoves. In closed fireplaces, solid fuels such as e.g. Wood or coal, fuel oil or gas are used.

In central heating systems, heat is converted centrally for one or more buildings, and the heat is supplied to the individual rooms with a heating medium. In contrast to the radiators in central heating systems, storage heaters are emitted mainly by radiation and only to a very small extent by convection. This enables a physiologically optimal indoor climate to be created. Compared to long-life stoves, storage stoves have the advantage that they burn the fuels for a short period at high temperatures. As a result, higher efficiency and more complete combustion can be achieved with storage furnaces than with continuous combustion furnaces.

Since individual heaters only heat a single room in conventional operation, they are often supplemented by central heating with their own boiler to ensure that all rooms in a house are heated. In such a case, at least two heat generators are required to heat an entire house. This leads to correspondingly high acquisition costs. The company was therefore looking for a way to use individual heating devices as heat generators for central heating.

According to the prior art, various types of individual heating devices are known which are equipped with at least one heat exchanger. A liquid or gaseous heat carrier flows through the heat exchangers. Water is mostly used as a heat transfer medium. When the individual heating devices are heated, they give off heat to the heat carrier. The heat exchanger is fed from the heat exchangers through a pipe network to the rooms to be heated. The heat is given off to the rooms via radiators or underfloor heating.

For example, individual heating devices are known in which the heat exchangers are installed in the walls. The subject of patent AT 387 083 (publication date November 25, 1988) is, for example, a stove, in particular a tiled stove, the combustion chamber and flue of which are surrounded by heat-storing walls in which heat exchangers through which a liquid heat carrier flows are arranged. The heat exchangers consist of copper pipes with attached fins. They are embedded in sand or another suitable material.

The patent specification CH 648 647 (publication date March 29, 1985) also describes a fireplace whose combustion chamber is delimited by a double jacket with water. This double jacket is connected to a heating system by cables. In addition, a water-bearing insert is also arranged in the fireplace, which consists of pipes and manifolds. The insert also forms the fire grate for the fuel. It is also connected to a heating system.

Furthermore, as is known, heat exchangers can be arranged in the interior of an individual heating device.

The published patent application DE 44 15 767 (day of disclosure 2.11.1995), for example, proposes a fireplace, in the interior of which two water containers are arranged which the flue gas pipes are passed through. The flue gases give off their heat through the walls of the flue gas pipes to the water in the water tanks. The water tanks are connected to a central heating system. Furthermore, laid-open specification DE 37 21 454 (disclosure date 12.1.1989) describes a heating system in which a high-temperature combustion chamber for solid fuels is connected to a water and / or air heat exchanger connected via a flue gas line.

The patent specification WO 94/14009 (publication date June 23, 1994) finally proposes a furnace which has a combustion chamber for solid fuels and an afterburning chamber. Channels lead from the afterburner to the flue gas pipe. Furthermore, it is equipped with a storage tank for a liquid heat transfer medium, in particular for water, which is surrounded by insulating walls. The space of the storage tank at least partially encloses the combustion chamber, the channels and the flue gas pipes.

All of the individual heating devices with heat exchangers mentioned have the major disadvantage that the heat exchangers must be installed during the manufacture of the individual devices. The heat exchangers can therefore not be used together with conventional individual heaters.

The subject of patent specification FR 2 567 625 (publication date 1/17/1986) is a heat exchanger with circulating water as the heat carrier, which can also be retrofitted in a fireplace or in certain ovens. The heat exchanger has the shape of a flat plate, which is attached to the rear wall of the combustion chamber of a fireplace or a furnace. The heated water is piped out of the combustion chamber. At least one wall of the combustion chamber must be drilled to allow the pipes to pass through. Another disadvantage of this heat exchanger is that it is directly exposed to the flames and flue gases. It is therefore heavily loaded and constantly polluted.

Heat exchangers, which are suitable for converting existing individual heating devices, especially existing storage heaters, are not yet known.

The present invention therefore has as its object to provide a storage heater for central heating with at least one heat exchanger, which is also suitable for retrofitting existing storage heaters. For the installation of the heat exchangers, you should not have to make any changes to an existing storage heater.

The object is achieved with the aid of the features of claim 1 according to the invention. Advantageous developments of the invention are the subject of the dependent claims.

The proposed storage heater is preferably designed as a soapstone storage heater. It is placed in front of a wall of a room or in a corner of the room in such a way that there is a gap between the walls of the room and the neighboring walls of the stove. A heat exchanger is placed in each space.

Each heat exchanger consists of a copper tube with turns. It is divided into long, straight sections and short sections bent by 180 °. All sections are on one level. There is a curved section between each two straight sections. The straight sections are arranged parallel and unaligned to each other.

Thanks to this shape, the heat exchanger is very flat. Also adjacent to the free end of one of the outer, straight sections is a piece of pipe which extends at right angles to this first outer, straight section in the direction of the opposite, outer, straight section. As a result, the two end sections of the heat exchanger lie close together, which simplifies connection of the heat exchanger to a line network. In addition, a piece of pipe protrudes at right angles on the first, outer, straight section. This piece of pipe has a valve on the free end face which serves to vent the heat exchanger. The heat exchanger can either be connected to the pipe network of an existing central heating system or to a pipe network specially installed for the storage heater. The invention is explained in more detail below on the basis of exemplary embodiments. It is also described in the drawings. Show it:

Figure 1 is a schematic representation of a proposed storage furnace with its own pipe network, which conducts the heated water to radiators.

2 shows a schematic representation of a proposed storage furnace with its own pipeline network, which conducts the heated water to a second storage furnace;

3 shows a schematic illustration of a proposed storage furnace, the heat exchanger of which is connected to a line network of an existing central heating system;

4a is a top view of a proposed storage heater which is set up next to a room wall;

4b is a top view of a proposed storage heater which is installed in a corner of the room;

Fig. 5 shows a section through a proposed storage heater, which is placed next to a room wall and

Fig. 6 is a front view of a heat exchanger of a proposed storage furnace.

Storage ovens 1 made of soapstone are used in the exemplary embodiments. Soapstone is extremely heat and acid resistant, alkali insensitive, antistatic and diffusion tight. It also has a high heat storage and thermal conductivity. Such soapstone storage stoves 1 are available on the market. Wood is primarily provided as fuel for these soapstone storage stoves 1. However, they can also be retrofitted with an oil or gas burner. This is particularly advantageous for older people who are no longer strong are enough to constantly provide the necessary firewood.

Storage furnaces 1, which are provided as heat sources for central heating, are dimensioned somewhat larger than storage furnaces, which have the function of individual heating devices.

Models of such soapstone storage stoves 1 are available which are placed next to a room wall 2 (cf. FIGS. 4a and 5). In these cases, the rear wall 3 of a storage furnace 1 faces the room wall 2. Between the rear wall 3 and the room wall 2 there remains a narrow space 4 in which a heat exchanger 5 is arranged to run vertically. Another heat exchanger 5 is preferably arranged horizontally on the top of the storage furnace 1.

The floor plan of the soapstone storage furnace 1 set up next to a room wall 2 is essentially rectangular in the exemplary embodiment. The soapstone storage furnace 1 is, for example, 164 cm high, 126 cm wide and 64 cm deep. There are also models of soapstone storage heaters 1 that are installed in a corner of the room (cf. FIG. 4b). In these cases, two side walls 7 of a storage furnace 1 each face a room wall 2. Between each of these two side walls 7 and the corresponding room wall 2 there is an intermediate space 4 in which a heat exchanger 5 is arranged to run vertically. If such a soapstone storage furnace 1 has too little power, a horizontally extending heat exchanger 5 can also be arranged here on the top of the furnace.

The floor plan of the soapstone storage furnace 1 set up in a corner 6 of the room is essentially pentagonal in the exemplary embodiment. The furnace side walls 7 facing the room walls 2 are the widest and also run at right angles to one another. The corner model of the soapstone storage stove 1 is, for example, 165 cm high and 75 cm wide.

So that the rear wall 3 or the side walls 7 of the storage furnace 1 do not have to be changed, the heat exchangers 5 are fastened to the room walls 2. For example, pipe clips (not shown) can be used for fastening. The Heat exchangers 5 rest on the outside of the furnace walls 7, 3.

Each heat exchanger 5 consists of a copper tube 8 which has turns (cf. FIG. 6). It is divided into long, straight sections and short sections bent by 180 °. All sections are on one level. There is a curved section between each two straight sections. The straight sections are parallel and not offset from one another. Thanks to this shape, the heat exchanger 5 is very flat and has an optimal contact surface. Also adjacent to the free end of one of the outer, straight sections is a piece of pipe which extends at right angles to this first outer, straight section in the direction of the opposite, outer, straight section. It is thereby achieved that the two end sections of the heat exchanger lie close together, which simplifies connection of the heat exchanger 5 to a line network. In addition, a pipe section 18 protrudes from the first, outer, straight section at right angles. This pipe section 18 has a valve on the free end face, which serves to vent the heat exchanger 5. A liquid heat transfer medium flows through the copper tube 8. Water is preferably used as the heat transfer medium.

In order to distribute the heat from the storage furnace 1 into the rooms of a building, a line network 10 can be installed, for example, which runs directly from the heat exchanger 5 or from the heat exchangers 5 to the radiators 11 (cf. FIG. 1). A second storage oven 17 can also take the place of the radiators 11 (cf. FIG. 2). In these cases, one end 9 of the copper pipe 8 of the heat exchanger 5 is connected to the flow 12 and the other end 9 to the return 13 of the line network 10.

Line networks 10 of a known type can be used. Such line networks can be designed as two-pipe or single-pipe systems. In a two-pipe system, the pipe string for the flow 12 and the pipe string for the return 13 are routed separately from one another (see FIG. 1) . Single-pipe systems have a common pipe string for the flow and the return. The water delivery is preferably carried out by one or more pumps 14. Because of the water expansion during heating, the line network 10 includes an expansion vessel (not shown), which can be arranged at the highest point of the line network 10 in open systems and as a pressure vessel at the bottom or top of the line network in a closed system. However, the line network 10 of an existing central heating system, the original boiler 15 of which is located, for example, in the basement of the building (cf. FIG. 3), can also be used for heat distribution. The original boiler 15 can either be completely dismantled or left in operation.

In the latter case, it is used primarily in emergencies, e.g. when on very cold days, the heating capacity of the storage furnace 1 is insufficient or the storage furnace 1 is defective. In this case, the heat exchanger 5 is installed in the return 13 of the existing network 10. The cooled water therefore flows from the radiators 11 first to the heat exchanger 5 of the storage furnace 1. The water is heated in the heat exchanger 5. The heated water is then fed into the basement to the original boiler 15. If the water temperature is sufficiently high, then the boiler 15 is bypassed via a mixing valve 16, and the water goes directly into the flow 12 of the line network 10. If the temperature of the water coming from the heat exchanger 5 is too low, then this will be in the Boiler 15 passed and additionally heated there.

If two heat exchangers 5 are used, they can be connected to the line network 10 either in parallel or in series.

The proposed storage heater 1 is preferably installed in the living room of a house. In this case, the living room is heated by direct heat radiation from the storage furnace 1, while the other rooms are heated via the line network 10 and the radiators 11 or the second storage furnace 17 connected to it. The storage furnace 1 can also in any another room, for example in the children's room, of the house. In this case, the living room is then also heated using radiators 11 or a second storage stove 17.

The proposed storage furnace 1 allows optimal use of the heat generated. Thanks to the combination of the storage furnace 1 with the line network 10 of a central heating system, several rooms of a house can be heated with the heat generated.

The heat exchanger 5 of the proposed storage furnace 1 can be used together with existing storage furnaces with little effort. The existing storage heaters do not have to be changed.

Claims

Patent claims

1. Storage furnace for central heating with at least one heat exchanger (5) connected to a line network (10), characterized in that the heat exchanger (5) in an intermediate space (4) between at least one wall (3, 7) of the storage furnace (1) and a room wall (2) is arranged.

2. Storage furnace according to claim 1, characterized in that the end sections (9) of the heat exchanger (5) connected to the line network (10) lie close together.

3. Storage furnace according to claim 1 or 2, characterized in that the heat exchanger (5) consists of a copper tube (8) which is bent in a meandering manner with sections running parallel to one another.

4. Storage furnace according to one of claims 1 to 3, characterized in that the heat exchanger (5) is flowed through by a liquid heat transfer medium.

5. Storage oven according to one of claims 1 to 4, characterized in that the storage oven (1) is a soapstone storage oven.

6. Storage furnace according to one of claims 1 to 5, characterized in that the heat exchanger (5) is connected to a pump (14).

7. Storage furnace according to one of claims 1 to 6, characterized in that two or more heat exchangers (5) are provided, wherein preferably a heat exchanger (5) is arranged lying on the top of the storage furnace (1).

8. Storage furnace according to claim 7, characterized in that the two or more heat exchangers (5) are connected in parallel or in series to the line network (10).

9. Storage furnace according to one of claims 1 to 8, characterized in that the heat exchanger (5) is in contact with the outside on at least one wall (3, 7) of the storage furnace (1).

10. Storage furnace according to one of claims 1 to 9, characterized in that the heat exchanger (5) to the line network (10) of an existing central heating system with a boiler (15) and a mixing valve (16) is connected.

11. Storage furnace according to one of claims 1 to 10, characterized in that the heat exchanger (5) to the radiator (11) and / or a further storage furnace (17) is connected.

12. Storage furnace according to one of claims 1 to 11, characterized in that a ventilation pipe (18) is arranged on the heat exchanger (5).