GB2194632A

GB2194632A - Flues for fuel-effect gas fires

Info

Publication number: GB2194632A
Application number: GB08710336A
Authority: GB
Inventors: Alan Pryke; Matthew Bright
Original assignee: Focal Point Fires PLC
Current assignee: Focal Point Fires PLC
Priority date: 1986-07-17
Filing date: 1987-07-10
Publication date: 1988-03-09
Also published as: GB8716336D0; GB8617519D0

Abstract

A fuel-effect gas fire comprises a gas combustion zone 2 which in use has incombustible elements having the appearance of burning coals or wood, a hood 1 above said combustion zone to gather gaseous combustion products from said zone, a flue portion 4 between said hood 1 and the exterior of a building in which the fire is situated to conduct said gaseous combustion products from said combustion zone to said exterior, and fan means 8 to assist the passage of gaseous combustion products along said flue portion. <IMAGE>

Description

SPECIFICATION Flues This invention relates to fuel-effect gas fires and flues therefor.

Fuel-effect gas fire have become very popular. These fires are fuelled by mains or bottled gas and incorporate incombustible elements which serve to give the appearance of, for example, a natural coal or log fire. Thus, in use, the fuel-effect gas fires provide a realistic imitation of natural fires. Out Convectaflame (Trade Mark) fires incorporate fuel-effect gas fires and provide a high heat output.

Hitherto fuel-effect gas fires could only be situated where a functioning chimney was available in order to allow escape of combustion gases, as in a natural fire. Thus, without a chimney (such as in many modern houses and flats), it has not been possible to have a fuel-effect gas fire.

We have now found it possible to allow for the situation of fuel-effect gas fires in rooms without a conventional chimney flue.

Thus, in one aspect, the invention provides a flue for a fuel-effect gas fire which comprises a hood above a gas combustion zone to collect gaseous combustion products from said zone, a flue portion to conduct said gaseous combustion products from the hood to the exterior of a building in which the fire is situated, and powdered means to draw combustion gases from said combustion zone to said exterior. The flue portion is generally substantially horizontal and passes through a hole in an external wall of the building.

In a further aspect, the invention provides a fuel-effect gas fire comprising a gas combustion zone which in use has substantially incombustible elements having the appearance of burning coals or wood, a hood above said combustion zone to gather gaseous combustion products from said zone, a flue portion between said hood and the exterior of a building in which the fire is situated to conduct said gaseous combustion products from said combustion zone to said exterior, and means to assist the passage of gaseous combustion products along said flue portion.

The combustion gases are preferably drawn through the flue with the help of a fan driven by an electric motor.

Embodiments of the invention are hereinafter described by way of example with reference to the accompanying drawings in which: Figure 1 schematically shows a flue in accordance with one embodiment of the invention; Figure 2 schematically shows a fire incorporating the flue of Fig. 1; Figure 3 schematically and partially shows an exploded view of a fire and flue in accordance with a further embodiment of the invention; Figure 4 schematically shows in cross-section a fire and flue in accordance with the invention and indicates the flow of combustion gases when in use; and Figures 5A and 5B schematically show in cross-section different locations for a fire in accordance with the invention.

In the Figs, a hood 1 is situated above a combustion zone 2 of a fuel effect gas fire 3.

The fuel-effect gas fire 3 may conveniently incorporate our Convectaflame (Trade Mark) convention box. The hood 1 collects combustion gases from the zone 2 and channels them into a flue portion 4. The low of combustion gases is indicated by the arrows in Fig. 4. As shown in Figs. 1 and 2, the flue portion 4 is conveniently of twin-walled construction having a rectangular cross-section and' comprising a telescoping inner part 5 and an outer part 6 which closely fits into a hole in an exterior wall of a building in which the fire is situated.

As shown in Fig. 3, the flue portion 4 may also be of twin-walled construction having a substantially circular cross-section and comprising telescoping inner 5' and outer 6' parts which fit in a hole in a wall. It will, of course, be appreciated that the cross-sectional shape of the flue is not generally important. The telescoping parts allow the length of the flue 4 to be adjusted according to the thickness of the wail. A cavity wall 7 is shown in Figs. 2, 4, 5A and 5B. The space between parts 5 and 6, and parts 5' and 6', of the flue portion 4 serves to insuiate and prevent spread of heat into the surrounding wall.

The flue portion 4 opens to the exterior of the building where a fan box 8 is provided. If appropriate, a safety cage, e.g. of wire mesh, may be provided over the fan box. The fan box 8 incorporates an electrically powered fan which draws the combustion gases from the combustion zone 2 via the hood 1 and flue portion 4. The flue portion 4 also serves as a silencer for the fan. If desired, however, additional sound absorbing material may be incorporated with the flue. Flashing may also be provided along the external top edge of the fan box 8 to prevent rain penetration.

A small paddle (not shown) may conveniently be provided within the inner part 5 of the flue portion 4. This paddle swings in the gas flow through the flue portion 4 and is connected to a microswitch which in turn is connected to a solenoid-activated gas valve to prevent operation of the fire in the event that combustion gas flow through the flue portion 4 is impeded. Alternatively, the fan box 8 may be provided with a differential pressure switch (not shown) which is sensitive to the amount of gas flow through the fan box and which will similarly cause the closure of a solenoid-activated valve in the gas line leading to the fire in the event that gas flow through the fan box in insufficient for effective removal of combustion gases.The differential pressure switch is connected to the solenoid (which is usually located inside the building) via wires passing through the conduit 9 shown in Fig.

3. The conduit 9 may pass through a hole in the wall provided for that purpose and may also carry the electrical cables for powering the fan.

The hood 1 may conveniently be bolted or clamped to the gas fire 3 and the joint thereby formed sealed with an appropriate gasket, e.g. of heat-resistant putty. Preferably, the hood 1 and gas fire 3 are secured together by means which are releasable from within the upper part of the combustion zone 2 to thereby facilitate removal of the gas fire 3 should servicing or repair be required.

Figs. 5A and 5B show two different locations of a fire 3 and flue 4 in accordance with the invention. In Fig. 5A the fire 3 is located adjacent the internal leaf 11 of cavity wall 7 and the flue 4 simply passes through a hole cut in the internal and external leaves of the wall 7. Where it is desired to reduce the amount of space required for the fire 3 in the room in which it is located, the fire 3 can be set back into the cavity wall 7 after removing a part of the internal leaf 11. The internal leaf 11 above the fire 3 is supported by lintel 10 .and the flue 4 passes through a hole in the external leaf of the wall 7. It will generally be necessary to build an additional outer leaf 12 of bricks to maintain a sufficient thickness of the wall 7. The arrangement of the type shown in Fig. 5B may be especially suitable for timber frame houses.

It will be appreciated that it is not essential to situate the fire 3 on an external wall of the building. Thus, if the fire is situated on an internal wall of the building, the flue portion 9 can be arranged to pass sideways along the internal wall and then through an external wall to allow passage of the combustion gases to the exterior of the building.

It will also be appreciated that the fan box 8 could be situated within the flue portion 4.

The fire 3 will generally be provided with a desired decorative surround and this will generally be arranged to hide the hood 1 and/or flue portion 4.

Claims

1. A fuel-effect gas fire comprising a gas combustion zone which in use has substan tially incombustible elements having the appearance of burning coals or wood, a hood above said combustion zone to gather gase ous combustion products from said zone, a flue portion between said hood and the exte rior of a building in which the fire is situated to conduct said gaseous combustion products from said combustion zone to said exterior, and means to assist the passage of gaseous combination products along said flue portion.

2. A gas fire according to claim 1 wherein the means to assist the passage of gaseous combustion products along said flue portion comprises an electrically driven fan.

3. A gas fire according to claim 2 wherein the fan is in a fan box located at the external end of the flue portion.

4. A gas fire according to any one of the preceding claims wherein means are provided to detect the flow of gaseous combustion products in the flue portion and to interupt gas feed to the fire if the flow of said combustion products in the flue is insufficient for effective removal of said combustion products from the combustion zone.

5. A gas fire according to claim 4 when dependent on claim 3 wherein said means comprises a differential pressure switch in the fan box to operate a solenoid-actuated valve in a gas line feed for the fire.

6. A gas fire according to claim 4 wherein said means comprises a paddle which may swing in the flue portion, which paddle serves to operate a microswitch to operate a solenoid-actuated valve in a gas line feed for the fire.

7. A gas fire according to any preceding claim wherein the flue is substantially horizontal.

8. A fuel-effect gas fire according to any preceding claim substantially as herein described.

9. A fuel-effect gas fire substantially as herein described with reference to the accompanying drawings.

10. A flue for a fuel-effect gas fire which comprises a hood above a gas combustion zone to collect gaseous combustion products from said zone, a flue portion to conduct said gaseous combustion products from the hood to the exterior of a building in which the fire is situated, and powered means to draw combustion gases from said combustion zone to said exterior.

11. A flue for a fuel-effect gas fire substantially as herein described with reference to the accompanying drawings.