GB2130361A

GB2130361A - Improvements in and relating to room heating apparatus

Info

Publication number: GB2130361A
Application number: GB08326035A
Authority: GB
Inventors: John Degan; James Corcoran
Original assignee: WATERFORD FOUNDRY Ltd
Current assignee: WATERFORD FOUNDRY Ltd
Priority date: 1982-09-29
Filing date: 1983-09-29
Publication date: 1984-05-31
Also published as: IE54023B1; IE822357L; GB8326035D0; GB2130361B

Abstract

Room heating apparatus adapted to be located in and to seal the entrance to a conventional open fireplace, and comprising an adjustable valve (6) enabling the flow of air through the apparatus to the fire zone to be regulated, and an air duct system (15a, 15c) within the apparatus enabling air to enter the apparatus from the room in which the fireplace is located and, without entering the fire zone, to be heated in the apparatus before being returned to the room. The apparatus enables the rate of combustion of fuel in the fireplace to be controlled and enables fuel to be converted into heat in an efficient manner. The apparatus may also have a back water boiler (10) and a thermostatic control mechanism (not shown). <IMAGE>

Description

SPECIFICATION Improvements in and relating to room heating apparatus The present invention relates to fireplaces and provides room heating apparatus adapted to be located in and to seal the entrance to a conventional open fireplace, the apparatus comprising (a) valve means enabling the flow of air through the apparatus to the fire zone to be regulated, and (b) duct means within the apparatus enabling airto enterthe apparatusfrom the room in which thefireplace is located and, without entering the fire zone, to be heated in the apparatus before being returned to the room.

Advantageously, the valve means enabling the flow of airto be regulated comprises a spin valve located towards the base of the apparatus. The spin valve is ideally located in a door providing access to the ashpan beneath the grate.

The apparatus includes a glass door which, when opened, allows solid fusel to be fed from the room through the apparatus into the fireplace.

Preferably, the duct means comprises a generally rectangular duct system including horizontallydis- posed lower and upper ducts adjacentthe bottom and top ofthe apparatus, the upper and lower ducts being joined together attheirends to two vertically disposed ducts, one at each side ofthe appartus.

In a particular construction according to the invention, the apparatus includes two castings, bolted or otherwise secured together to form a unit, the front casting having on its rear side adjacents its periphery a pair of mutually parallel U-shaped channel elements to receive the projecting limbs of a continuous U-shaped channel member on the rear casting and thereby to form a continuous duct within and adjacent the top, sides and lower region ofthe apparatus.

The invention will hereinafter be described more particularly with reference to the accompanying drawings which illustrate, by way of example only, a preferred embodiment thereof.

In the drawings, Figure lisa front elevation of a fireplace apparatus according to the invention; Figure 2 is a sectional side elevation on line Il-I I of Figure 1; Figure 3 is a sectional plan view on line Ill-Ill of Figure 2, certain parts being omittedforthe sake of clarity; Figure 4 is a partial sectional plan view on IV-IV of Figure 1; Figures 5,6 and 7 are partial sectional plan views on lines V-V, VI-VI and VII-VII respectively, of Figure 1; and Figure 8 is a partially cut away front elevation.

Referring to the drawings, and initially to Figures 1, 2 and 3 the fireplace apparatus comprises a front casting 1 and a rear casting 2, connected together to form a unit.

The front casting 1 has three recesses in which are located (a) a rectangular panel 3 having a series of apertures 29 which communicate with an elongated aperture 30 at the upper end in the front casting 1, (b) a glass door 4 providing access to the fireplace and grate 7 through a rectangular aperture 8 in the front casting l,and (c) a door 5 providing access to the ashpan belowthe grate 7. In the door5 is a manually adjustable spin valve 6.

The front casting 1 has a pair of U-shaped channel elements 12 which extend around the casting 1 adjacent its perimeter and into which project and are secured the ends of limbs 13 of a generally U-shaped channel member integral with the rear casting 2.

Co-operation of the U-shaped channel member of the rear casting 2 with the U-shaped channel elements ofthe front casting 1 form a continuous air duct or duct system within the apparatus, the duct being generally rectangularwhen viewed in elevation and having a lower horizontal branch 1 5a, two vertical side branches 1 sub and an upper horizontal branch 1 sic.

Thefrontand rearcasting 1 and 2 respectively are bolted together, in the manner shown in Figure 4, the bolt 16 passing through the front casting 1 and engaging the base 13a ofthe U-shaped channel member ofthe rear casting 2. The castings 1 and 2 are also bolted together by bolts 31, as shown in Figures 1 and 7.

Air inlets (not shown) to the duct are provided on each side ofthe lower branch 15a ofthe duct and an outlet 17 is provided in the upper branch, the outlet 17 being co-incident with an co-operating with the apertures 29 in the panel 3.

The air when heated in the lower branch 1 5a flows upwardly through the vertical side branches 1 5b to the upper horizontal brnach 1 5c from where it emerges into the room through the outlet 17 and apertures 29.

Thus the apparatus by conduction and convection heats and circulates air in the room. If desired, an electrically powered fan (not shown) may be provided toenhancethe,flowofairthroughtheductsystem.

Figures 2 and 3 showthe apparatus in a fireplace which has a back boiler 10 defined by side panels 1 Oa, a rear panel 10b, a transverse panel 1 Oc, a water inlet l0dandwateroutlet 10e.

An adjustable damper 8 (see Figure 2) is supported by a cradled pivot connection 7 on one of the rearwardlyextending lips2a ofthe rearcasting 2. Also supported on each lip 2a is a bracket 9which can be tighted againstthefireplace lintel 20. Connected to the rear of the upper transverse channel of the rear casting 2 are brackets (not shown) for supporting a plate (not shown) which acts as a heat sink and protects the lintel 20 from overheating.

The apparatus is installed by locating it in the fireplace entrance and then pushing it back until (see Figure 3) the backwardly extending lips 2a ofthe rear casting 2 contact the forward edges 19 ofthe back boiler side panels 1 Oa. The bottom and side edges of the appartus are then sealed using fire cement. The glass door 4 is then opened and the locating brackets9 are swung around their pivot points so thattheirfree ends engage the rear ofthe lintel 20. Bracket nuts 21 are then tightened to hold the apparatus in position.

The top edge is then sealed by filling the space between the front casing 1, duct system 3 and lintel 20 with fire cement. The sealing not only increases the efficiency of the apparatus but also prevents the entry into the room of dust, smoke and fumes from the fire zone. Unwanted draughts are also eliminated.

When the apparatus is in position, the damper 8 is adjusted to an appropriate setting to restrict loss of heat. The damper may be moved from the position shown, to any ofthethree other positions indicated by dotted lines in Figure 4.

The damper8 is fixed in position by engagement of one ofthe eyes 22 ofthe damper arm 23 with a stop pin 30fixedtothelip2a.

The glass door4 can be opened by latch 14(see Figures 1 and 7) and is hinged by hinge 11 (see Figures 1 and 6) so that it can be swung through a full 1800and so that it may easily be detached.

Belowthe grate 7 is an ashpan (not shown). Access to the ashpan is via door 5 which has a handle 5a.

In operation, the glass door4 is opened, and coal, turf or other solid fuel is loaded onto the grate. When the fire is lighting, the glass door 4 is closed and the spin valve 6 is opened fully, Air is drawin into the fireplace through the spin valve 6. When a good blaze has been established, if it is desired to sit in front of an open fire, the glass door4 may be opened. Alternatively,the glass door may be left closed and the spin valve 6 setto give the desired rate of burning. When the glass door 4 is closed, the room is heated primarily by convected airflow th rough the duct system and also by heat radiating from the fire through the glass door4 and from the apparatus.When the glass door4 is shut it is possible to regulate the airflow through the spin valve 6 and thereby to control the consumption of fuel and temperature in the room and ofthe water in the back boiler 10.

In the closed door mode, the fan (if provided) is switched on and the spin valve 6 is left partially open.

Room air enters the duct 15 via inlets 1 6where the air is heated. The heated air rises through the duct 1 sub when the air absorbs further heat before being returned to the room via outlet 17 and apertures 29.

It is generally unsafe to leave a fire in a conventional open fireplace unattended for a long period of time (i.e. overnight). Using an apparatus according to the invention,thefire may be left burning at night by closing the spin valve 6 (orthermostatwhen fitted). To enable the grate 7 to be stacked with sufficient fuel to lastthrough the night, the grate 7 has a vertical grate front7a which is somewhat higherthan that provided in a conventional fireplace. The glass door 4 is then closed and the adjustable spin valve 6 setforthe minimum flow of primary air, enabling sufficient primary airto enterthefireplace to keep the fire smouldering but not to allowthefire to blaze. The fan (if provided) is switched off.As the fire smoulders, very little heat gores up the chimney or is emitted as radiant heat; most ofthe heat is transferred to room air passing through the duct system by natural circulation, and in this way the room is keptwarm. In the morning the spin valve is reopened and the fire blazes almost immediately. Unattended burning times often to twelve hours can be achieved using an apparatus according to the invention.

Figure 8 illustrates a thermostatic control mechanism forth primary airflow. A primary air inlet25 is provided at bottom ofthe left hand side ofthefront casting 2. The thermostatic control mechanism comprises a lever arum 27 having afulcrum or pivot point at its upper end, an efforts point midway along its length, and a load point at its lower end. The position ofthe fulcrum is set by the screw adjustment 28. A sensor 29, one end of which projects into thefire, is connected at its other end to the lever arm 25,the point of connection constituting the load point When the sensor expands orcontracts the leverswingsclock- wise or anticlockwise (as seen in Figure 8), about its fulcrum point.This movement of the lever arm admits more or less air into the air inlet 25. The thermostatic control mechanism may be adjusted by adjusting the fulcrum point by means of screw adjustment 28.

Thefuel efficiency of a fire provided with an apparatus according to the invention is much greater than the fuel efficiency ofan open fire. The apparatus enables the fuel burning rate to be controlled, and reduces the demand for combustion air. Typical open firess remove approximately two hundred and forty cubic metres of air per hourfrom a room, whereas an apparatus according to the invention require approx imately twenty five per cent ofthatvolume of airfor efficient working.

Fires in open fire places are approximatelyfifteen per cent efficient due to heat loss going up the chimney. By the use of an apparatus according to the invention,thefuel efficiency could be increased to more than sixtyfive per cent.

The burning rate for coal may be from one kilogram to two kilograms per hour and this could provide sufficient heat from an indirect domestic hotwater cylinderfeeiding six radiators.

The apparatus shown in Figures 1 to 7 weighs about forty five kilograms and is designed for a fireplace 0.4 metres to 0.46 metres wide and 0.56 metres high.

Claims

1. Room heating apparatus adapted to be located in and to seal the entrance to a conventional open fireplace, and comprising (a) valve means enabling the flow of airthrough theapparatustothefirezoneto be regulated, and (b) duct meanswithin the apparatus enabling air to enterthe apparatusfrom the room in which the fireplace is located and, without entering the fire zone, to be heated in the apparatus before being returned to the room.

2. An apparatus as claimed in Claim 1, in which the valve means enabling the flow of airto be regulated comprises a spin valve located towards the base of the apparatus.

3. An apparatus as claimed in Claim 2, in which the spin valve is located in a door providing access tothe fireplace ashpan beneath the grate

4. An apparatus as claimed in Claim 1, including a door which, when opened, allows solid fuel t(l be fed from the room through the apparatus to the fireplace.

5. An apparatus as claimed in any one of the preceding claims, in which the duct means comprises a generally rectangular duct system including horizontally disposed lower and upper ducts adjacent the bottom andtop ofthe apparatus,the upperand lower ducts being joined together at their ends by two vertically disposed ducts, one at each side of the apparatus.

6. An apparatus as claimed in Claim 5, in which an inlet is provided at each end of the lower duct and an airoutlet is provided intermediate the ends of the upper duct.

7. An apparatus as claimed in any one of the preceding claims, in which the apparatus includes two castings, bolted or otherwise secured together to form a unit, the front casting having on its rear side adjacent its periphery a pair of mutually parallel U-shaped channel elements to receive the projecting limbs of a continuous U-shaped channel member on the rear casting and thereby to form a continuous duct within and adjacentthetop, sides and lower region of the apparatus.

8. An apparatus as claimed in any one of the preceding claims, including an adjustable baffle for setting the size of the entrance from the fireplace to the flue.

9. An apparatus as claimed in any one of the preceding claims, in which fixing brackets are provided for securing the apparatus in position in the fireplace entrance, the fixing brackets being pivotally mounted on the apparatus, so that each bracket may be swung into a position in which it engages the rear ofthefireplace lintel and thereby secures the apparatus in position.

10. Apparatus as claimed in anyoneofthe preceding claims including means on the apparatus for protecting the fireplace lintel from overheating.

11. Apparatus as claimed in Claim 7, including means for protecting the lower section of the duct system from overheating.

12. Apparatusas claimed in any one of the preceding claims, including a fan for driving air through the duct system.

13. Apparatus as claimed in any one of the preceding claims 2 to 12 inclusive, in which the adjustable flow valve is a manually operable spin valve.

14. Apparatus as claimed in anyone of Claims 1 to 12 inclusive, in which th e adjustable flow valve is thermostatically controlled.

15. Apparatus for use in controlling the flow of air through a fireplace, substantially as herein described with reference to, and as illustrated in, Figures 1 to 7 of the accompanying drawings.

16. Apparatus for use in controlling the flow of air through a fireplace, substantially as herein described with reference to and as illustrated in the accompany ingdrawings.