GB2044441A - Water heating arrangements in stoves - Google Patents

Abstract

Open-stoves and fires generally have inner and outer spaced casings (2,3:4,5) around the hearth area (33) and the flue-gas channel (32). The space between these casings is divided into at least two sections (10, 11) so that air can flow up the stove in one section and down the stove in the other section. The air flowing through the space absorbs heat, and one or more pipe systems (35), through which a liquid flows, are arranged to be heated by the air. The pipe system (35) may be mounted in the space or in a closed unit (44 Fig. 5) mounted in proximity to the stove. <IMAGE>

Description

SPECIFICATION An open-stove, fire or tile-stove The present invention relates to open-stoves, fires, tile-stoves or the like.

In an open-fire, stove, tile-stove or the like in which the hearth area with flue-gas channel is surrounded by a space, heat from the hearth area and from the flue-gas channel is supplied to said space. Air can be constrained to flow through said space and said air will be supplied during its passage with heat from the hearth area and fluegas channel. It is an object of this invention to provide a stove in which the heat supplied to the air passing through the stove can be utilized.

According to the present invention there is provided a stove or fire having a hearth and a flue channel, inner and outer spaced casings surrounding the hearth and the flue channel, the space between said casings being divided into two or more sections through which a gaseous medium can flow, an inlet and an outlet for said gaseous medium communicating with said space, and one or more pipe systems arranged to contain a liquid and arranged to be heated by the heat absorbed by said gaseous medium as it flows through said sections.

In an embodiment, the pipe system is arranged in a unit outside the stove through which the air from the stove may pass.

The liquid absorbs heat energy from the air and the heated liquid can be used in various ways such as for hot water in the building or for heating other areas by way of a central heating system. The pipe coils can also be connected to a heating system for a building using a normai boiler with radiators connected thereto through which water flows. In addition, the air leaving the stove still retains sufficient heat energy to be used for other purposes.

In an embodiment, the pipe systems are connected at their outlet ends to a thermostat which senses the temperature of the liquid leaving. If this temperature becomes too high the flow of air through the surrounding space around the hearth area and flue-channel will be limited.

This can be achieved, for instance, with the aid of a damper cooperating with the surrounding space or by regulation of a fan affecting the flow of air through said space.

The thermostat may be arranged to keep temperature of the liquid in the pipe coils below 1000C.

A thermostat may also be used to sense the temperature of the air. This thermostat regulates the air flowing through the surrounding space in the stove in such a way that the air which has emitted energy to liquid does not exceed 800C.

Embodiments of the present invention will hereinafter be described, by way of example, with reference to the accompanying drawings, in which: FIG. 1 shows an open-fire provided with a surrounding space which is divided into two parts, a pipe coil being arranged in one of the parts, FIG. 2 shows a similar open-fire to that of Figure 1, seen from the rear and being provided with a pipe coil in the other part of the surrounding space, FIG. 3 shows a cross section through an openfire similar to Figure 1 in which a pipe coil is arranged in both parts of the surrounding space, FIG. 4 shows a longitudinal section through an open-fire similar to Figure 1, FIG. 5 shows a separate unit for mounting in proximity to an open-fire, and FIG. 6 shows a vertical cross section of a stove similar to Fig. 1 in which the pipe coils are arranged in a separate unit as in Figure 5.

Figure 1 shows an open-stove having an inner casing 2 for the hearth area 33 of the stove (see Fig. 4). The inner casing 2 is connected to a fluegas channel 32 (see Fig. 4) formed by an inner casing 3. Said inner casing 3 becomes wider towards its top as can be seen in Figure 1. The inner casing 2 and 3 is surrounded by an outer casing spaced from the inner casing. The outer casing is formed of a lower part 4 surrounding the hearth area and an upper part 5 surrounding the flue-gas channel. The outer and inner casings are closed at the top by means not shown so that only an opening for the flue-gas channel 32 remains.

The two casings 2, 3 and 4, 5 are closed at the bottom. The space formed around the inner casing is divided into two by partition walls, one of which is designated 9. The other, which is not visible, is identical. It is evident that only one partition wall need be used if this is divided at the top to leave space for the widening of the flue-gas channel 32.

A rear space 10 is formed to the right of the partition wall 9. The space in front of the partition wall is designated 11. Due to the hearth area 33, the front area around the actual hearth is divided into two sections, a righthand section 1 3 and a lefthand section 1 2. At the bottom of each of said sections is an outlet opening 1 6 which is regulated by a sliding damper by means of a damper lever 1 5. A corresponding opening, damper and lever are also to be found in the lefthand section. The outer casing may be provided at the top with a damper, not shown, which can be opened.The two partitions, the visible one of which is designated 9, do not reach all the way to the top of the stove, which means that the rear space 10 is in communication with the front space 11 in the upper part of the stove.

As can be seen in Figure 4, the outlet opening 1 6 communicates with an outlet pipe 1 8 and the outlet opening 20 communicates with an outlet pipe 19.

The open-stove shown in Figure 1 is provided with two doors 21 and 22 mounted on hinges which can be kept closed by means of a retaining means 23.

The outer casing 4 and 5 is provided with an insulation layer 8 of suitable insulating material on its rear surface. The layer 8 may be provided on the outside with a covering plate. The side and front surfaces of the outer casing may also be similarly insulated. An insulating layer 24 on the front surface is illustrated in Figure 6.

The open-stove is provided at the bottom with a fan 25 (see Fig. 6), a connection pipe 26 being at the exhaust of the fan to connect the fan to the rear space 10. A pipe coil 35 is arranged in the front space 11 and may be provided with outwardly directed flanges 36 to increase the heat-absorbing surface of the pipe coil. The pipe coil is provided with an inlet connection 34 and an outlet connection 38. A thermostat 37 is provided upstream of the outlet connection 38 to sense the temperature of the liquid passing through the pipe coil. The liquid in the pipe coil is preferably water.

The connections 34 and 38 may be connected to one or more systems requiring heated water. For instance, they may be connected to a hot water system and/or to a central heating system for a building.

The stove described above functions in the following manner: It is assumed that water is supplied at the connection 34 and heated water removed at connection 38 and that a combustion process is in progress in the hearth 33.

Furthermore, air is supplied to the rear space 10, which flows up and then down along the front space 11 and is then transported to the outlet pipes 18 and 1 9 as shown in Figure 4. Transport of the air is promoted by the fan 25. The fan 25 draws in air from the surroundings. During its passage through the rear space 10 and the front space 11 the air is heated and the heated air transfers thermal energy to the pipe coil 35. Thus the water passing through the pipe coil is heated.

Since air is the transfer medium the liquid flowing in the pipe coil is prevented from being heated to too high a temperature. However, to be on the safe side the thermostat 37 is provided and is set so that the liquid does not exceed a predetermined temperature, for example, 1 000C. If this temperature is exceeded the thermostat can, for instance, arrange for the or each of the dampers to be opened or it can turn off the fan, thus reducing the rate of flow of the air in the spaces 10 and 11.

If required, the thermostat can act to control both these operations at the same time.

Figure 2 shows an open-stove of the same type as in Figure 1. The difference between the stove shown in Figure 2 and that shown in Figure 1 is that the pipe coil 40 in Figure 2 is located in the rear space 10 whereas the pipe coil in Figure 1 is located in the front space 11. In other respects the arrangement shown in Figure 2 functions the same as that of Figure 1. In Figure 2 the inlet connection is designated 39, the outlet connection is designated 43 and the thermostat is designated 42. The radially, outwardly directed flanges of the coil are designated 41.

Figure 3 shows a cross section through an open stove in accordance with Figure 1. In the cross section a third way of arranging a pipe coil is shown and is designated 51. The pipe coil is arranged in both the spaces 10 and 11 and thus penetrates through the partition wail 9. In other respects the arrangement of Figure 3 functions the same as those of Figures 1 and 2.

Figure 5 shows an example of an open-fire or stove in which the pipe coils are located outside the stove itself. An entirely closed unit 44 is provided, and may be externally insulated with, for example, mineral wool. Both outlet pipes 18 and 1 9 from the stove are connected to the unit 44 and the unit 44 is also provided with an outlet conduit 45 containing a thermostat 46. A pipe coil 48 is arranged in the unit, preferably provided with outwardly directed peripheral flanges 49. The pipe coil has an inlet connection 47 and an outlet connection 51. A thermostat 50 is provided upstream of the outlet connection 51.This arrangement functions as follows: The unit 44 is provided via the outlet pipes 1 8 and 1 9 with heated air from the open-fire or stove, the air passing over the pipe coil and heating the liquid flowing therethrough, which liquid is, in the majority of cases, water. When the heated air has passed over the coil it passes to the outlet conduit 45 for the air, which still has a certain amount of heat which can be used for other purposes. A thermostat 46 is provided in the outlet pipe 45 and senses the temperature of the exit air.This thermostat 46 arranged to reduce the air flow, for example, by turning off the fan 25 and/or opening the damper 7 illustrated in Figure 3, if the air is warmer than a predetermined temperature, say 800 C. The coil 48 is also provided with a thermostat actuating said damper and fan when the temperature of the water exceeds 1000C.

Figure 6 shows an example of how the unit 44 can be arranged together with an open stove.

Figure 1 shows a pipe coil 35 arranged in the upper part of the front space 11. However, instead of one coil 35, it may under certain circumstances be practical to have two coils, in which case one of them is arranged in the lefthand side space 1 2 and the other in the righthand side space 1 3. Such location reduces the risk of over heating of liquid in said pipe coils since the heat in the hearth area 33 has an upward radiation direction rather than lateral.

Since the coils according to the present invention do not come into contact with either flue-gas or flame, the risk of over heating and explosion is reduced. Ali the coils according to the present invention only come into contact with air or gas which has been heated by flue-gas or flames from the hearth area.

Claims (6)

1. A stove or fire having a hearth and a flue channel, inner and outer spaced casings surrounding the hearth and the flue channel, the space between said casings being divided into two or more sections through which a gaseous medium can flow, an inlet and an outlet for said gaseous medium communicating with said space, and one or more pipe systems arranged to contain a liquid and arranged to be heated by the heat absorbed by said gaseous medium as it flows through said sections.

2. A stove or fire as claimed in Claim 1, wherein the or each pipe system is arranged in said space.

3. A stove or fire as claimed in Claim 1 or 2, wherein at least one pipe system is arranged in a separate unit connected to said outlet for said gaseous medium.

4. A stove or fire as claimed in any preceding Claim wherein a plurality of pipe systems are provided, the systems being connected together in series or in parallel.

5. A stove or fire as claimed in any preceding Claim, wherein the or each pipe system includes temperature sensing means arranged to regulate the flow of the gaseous medium such that the liquid in the pipe system does not exceed a predetermined value.

6. A stove or fire substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.