GB2288656A - Boiler:burner mounting - Google Patents

Abstract

A boiler comprises a heat exchanger 1 through which a burner 30 is mounted and, with the combustion chamber in its normally intended attitude of use, the burner is mounted on a side of the heat exchanger which is inclined out of both the horizontal and vertical planes. This arrangement provides for the burner to be manoeuvred out of the combustion chamber whilst remaining substantially within the volume prescribed by the boiler sides. <IMAGE>

Description

IMPROVEMENTS IN AND RELATING TO BOILERS Field of the Invention The present invention relates to boilers, especially wall mounted boilers.

Backqround to the Invention In a typical oil-fired boiler in which water is heated, a burner sits directly adjacent to a combustion chamber, extending through a heat exchanger, and firing horizontally into the combustion chamber as described, for example, in UK patent No GB 2 195009 A This arrangement has disadvantages in situations where the burner needs to be removed from the boiler, for example, to allow access for servicing, since there is a trade-off between accessibility for servicing and the overall size of the boiler for a given heat output. There is an increasing demand for boilers to be as compact as possible so that, for example, they can be fitted neatly between kitchen units on either the wall or the floor.

In this context wall mounted boilers present special problems since the housewife often requires the boiler to fit within a run of wall cabinets with no gaps on either side of the boiler i.e flush fitting. The consequence of this is that all servicing and maintenance activities must take place within the confines of the boiler housing.

Attached to the burner is a blast tube which, in use, extends into the combustion chamber, through the water jacket. In order to remove the burner from the boiler, there must be sufficient space for the burner to be moved in a horizontal direction to enable the blast tube to clear the edge of the water jacket. This results in a significant volume of empty space inside the boiler housing which, in normal use, is unoccupied. The size of the boiler casing could be reduced if the casing panel adjacent the burner were removable to permit access and withdrawal of the burner. However, apart from the added expense of manufacturing a removable panel, the same volume of space as before would be required in order to remove the burner, albeit outside the actual boiler casing in this case, which is undesirable in a modern compact kitchen.In this case the boiler could not be mounted close to adjacent units or in the corner of a room because of the need for the volume of unoccupied space next to the burner. For these reasons it is standard practice to fit the burner at the front of a wall-mounted boiler, access being gained by removing the front panel. This usually results in the boiler standing proud of any surrounding wall cupboards.

Alternatively the burner can be mounted facing vertically upwards or downwards into the combustion chamber. These configurations present their own problems in tenns of burner performance. For example, heat from a downward-facing burner will tend to rise up and increase the temperature of the burner unit itself, leading to reduced working life.

The present invention seeks to overcome these problems and to provide an improved burner mounting assembly.

Summarv of the Invention According to the first aspect of the present invention, in its broadest sense, there is provided a combustion chamber for a boiler comprising a heat exchanger through which a burner is mounted characterised in that with the combustion chamber in its normally intended attitude of use, the burner is mounted on a side of the heat exchanger which is inclined out of both the horizontal and vertical planes.

This arrangement provides for the burner to be manoeuvred out of the combustion chamber whilst remaining substantially within the volume prescribed by the heat exchanger sides. It thus provides a particularly compact boiler arrangement with little or no wasted space within the boiler housing.

Preferably the burner is mounted on a side of the water jacket which is inclined at substantially 45" relative to the vertical.

In a particularly preferred embodiment the burner is mounted on a side of the water jacket which is inclined at substantially 30 to the horizontal or to the vertical.

In a preferred means for mounting the burner onto the heat exchanger the burner is mounted on a quarl plate characterised in that at least one of the burner mounting points is distanced from the quarl plate itself.

This invention is intended to encompass a boiler incorporating a combustion system as herein described.

Brief Description of the Drawings Preferred embodiments of the present invention will now be more particularly described by way of example, with reference to the accompanying drawings wherein: Figure 1 shows a so-called exploded view of a boiler incorporating a combustion chamber according to the first embodiment of the invention; Figure 2 shows a side elevation of a combustion chamber according to the first embodiment within a boiler housing; Figure 3 shows the burner mounting details.

Description of the Preferred Embodiments The present embodiments represent currently the best ways known to the applicant of putting the invention into practice. But they are not the only ways in which this could be achieved. They are illustrated, and they will now be described, by way of example only.

Referring first to Figure 1, this illustrates a partially sectionalised exploded view of an oil-fired boiler. This comprises in essence a heat exchanger 1 incorporating a burner assembly 30. These are mounted inside a casing or housing made up of a number of panels 7 to 12. The various components are described in Table 1. From time to time the burner assembly has to be separated from the heat exchanger and removed from the boiler casing for servicing or replacement. To do this the blast tube 31 has to be drawn clear of the heat exchanger, as shown in Figure 1, before the burner assembly can be removed.

In this invention the burner 30 is deliberately mounted on one face of the heat exchanger which is inclined with respect to both the horizontal and vertical planes when the boiler is in its normal.attitude of use. Thus, in this illustration the face 32 of the heat exchanger is at approximately 45" to the two adjoining faces 33 and 34.

It has been discovered that this arrangement results in a number of worthwhile advantages. Firstly, mounting the burner at this sort of angle retains the advantages of a generally horizontally mounted burner without the disadvantages of vertical mounting. Secondly, the burner assembly is withdrawn into space which inevitably exists between the casing and the heat exchanger, so optimum use is made of the space within a rectangular boiler housing. Thirdly, the angled entry of hot combustion gases into the lower part of the combustion chamber positively improves their circulation within the boiler and leads to enhanced efficiency for any particular size of boiler.

Figure 2 illustrates clearly how this arrangement leads to the minimum of space required by the heat exchanger 1 and the boiler casing. There is always a requirement for controls on this type of boiler and these can conveniently be situated beneath the heat exchanger in the space shown as 35 in Figure 2.

This illustrates clearly what a space-saving advantage this invention provides.

In Figure 2 the burner assembly is mounted at an angle of between 30 to 450 to the horizontal. In tests it has been established that a wide variety of angles can be used to good effect. However, angles between 30 and 45" have been found to give optimum burner and boiler performance whilst still allowing easy removal of the burner assembly.

The size of the burner port is dependent upon the method of mounting the burner, and is preferably as large as possible to facilitate servicing once the burner has been removed. The burner can be simply mounted directly onto one face 32 of the heat exchanger, in which case the size and shape of the burner port is dictated by the burner's blast pipe. A larger burner port is possible if the burner is mounted on a quarl plate which is then, in turn, mounted onto the side of the water jacket.

Mounting the burner at an angle like this has necessitated redesign of the burner assembly mounting. These burners are relatively heavy and mounting them at an angle results in the uppermost mounting point experiencing a turning moment at all times. It also means that the lower mountings are hard to access. This has been overcome by the arrangement shown in Figure 3.

A quarl plate 26 is mounted over an aperture in the heat exchanger 1. The burner assembly is bolted to one of the upper quarl plate mounting studs A It is also supported on a bracket 40 extending away from the quarl plate. A stud on the burner slides into a corresponding slot in the bracket 40. To remove the burner top nut A is removed and bottom nut B is loosened. The burner can then be twisted, anti-clockwise in this illustration, and removed as a complete unit. Thus a two point mounting of the burner has been achieved.

The natural tendency of the burner to pivot about the upper fixing point A brings with it an added advantage. In this configuration the burner tends to press at all times against the seal between the quarl plate and the burner assembly itself. Even if bolt B becomes slack a good seal can be maintained.

This invention has the added advantage that it can be incorporated into any boiler using conventional construction techniques. Specifically, standard metal folding and welding techniques can be employed; conventional boiler furniture and baffles may be used and front servicing is possible.

This technology makes it possible for the burner assembly on a wall-mounted boiler to be side-mounted. This in turn means that the boiler can be slimmer and to correspond in size and shape to a conventional kitchen wall cupboard.

It is even possible to fit such a boiler inside a cupboard as a result of this invention to conceal it from view completely.

ITEM DESCRIPTION 1 Heat Exchanger short boiler only 2 Baffles 3 Inspection Plate assembly complete 4 Control Panel - complete 5 Insulation set - complete 6 Heatshield r- 7 Back Panel assembly 8 LIH Panel - complete FVH Panel - complete 10 Top Panel 11 Bottom Panel assembly 12 Door Panel assembly 13 75 mm conventional flue plate 14 Sight Glass assembly 15 Sight Glass holder 16 Sight Glass 17 Webglass gasket 18 Inspection Plate insulation 19 Inspection Plate gasket 20 Drain Cock 1/2 BSP 21 22mm x 3/4 BSP Female Coupling 22 Washer 23 Fire Valve Clip 24 Oil Entry Bulkhead Fitting 25 Nylon Washer 26 Quarl Plate 27 Quarl Plate Insulation 28 Quarl Plate Gasket TABLE l

Claims (5)

1. ClAIMS: 1. A combustion chamber for a boiler comprising a heat exchanger through which a burner is mounted characterised in that with the combustion chamber in its normally intended attitude of use, the burner is mounted on a side of the heat exchanger which is inclined out of both the horizontal and vertical planes.
2. 2. A combustion chamber system according to Claim 1, wherein the burner is mounted on a side of the water jacket which is inclined at an angle of between 30 to 45" relative to the horizontal.
3. 3. A combustion chamber as claimed in any preceding Claim wherein the burner is mounted on a quarl plate characterised in that at least one of the burner mounting points is distanced from the quarl plate itself.
4. 4. A combustion chamber substantially as herein described with reference and as illustrated in any combination of the accompanying drawings.
5. 5. A boiler incorporating a combustion chamber system as claimed in any preceding Claim.