EP1880147A2

EP1880147A2 - Central heating system

Info

Publication number: EP1880147A2
Application number: EP06726767A
Authority: EP
Inventors: Lee Mckeith
Original assignee: McKeith Lee
Current assignee: McKeith Lee
Priority date: 2005-04-14
Filing date: 2006-04-13
Publication date: 2008-01-23
Also published as: WO2006109080A2; WO2006109080A3

Abstract

A central heating system (100) comprises a boiler (16) for heating water, a flow (56) of the heated fluid to radiators (14) distributed around an area (12) to be heated, and a return (58) of the fluid once it has released some of its heat to the radiator. The flow is within the return as a composite pipe (40). It takes a single route from the boiler to each radiator in turn. The invention also provides a radiator fitting (50, 50') that is fixed in place during first-fix of the plumbing installation for the central heating system, in which sealed branches (52', 54') of the fitting are spaced to fit standard radiators. This arrangement also facilitates testing using an end-stop valve (120) which either connects flow and return lumens in the composite pipe, or seals them when the central heating system is in use.

Description

Central Heating system

This invention relates to central heating systems, particularly domestic heating systems comprising a boiler for heating a heat transfer fluid (typically water) , means flowing the heated fluid to radiators distributed around an area to be heated, and means returning the fluid once it has released some of its heat to the radiator. Such means generally comprise a flow pipe and a return pipe.

Our copending application number GB0507559 describes a system in which a central heating system comprises a boiler for heating a heat transfer fluid, means flowing the heated fluid to radiators distributed around an area to be heated, and means returning <the fluid once it has released some of its heat to the radiator, characterised in that said means flowing the heated fluid is contained within said means ' returning the fluid between the boiler and at least a first radiator and/or between radiators.

Indeed, said means flowing and returning may comprise a composite pipe having an inner lumen for said flow and an outer, surrounding lumen for said return.

An advantage of this arrangement is that any heat loss from the flow is accepted by the return, which is itself returned to the boiler where that heat is not lost but is recycled. Of course, the return is consequently hotter than it would otherwise be, and therefore loses more heat itself ^'to the environment, and . which therefore still represents wasted heat. However, since the return is nevertheless still a lower temperature than the flow would normally be, and the heat loss from the flow has . been essentially eliminated, there is still a marked saving in energy loss.

With this arrangement, it is possible to lead the combined flow and return direct from the boiler on a single route to each radiator in turn. This leads to an advantageous position the subject of the present application.

Traditionally, central heating installation in a new- build house or other structure is a two-stage job. First, the skeleton of the building is erected, without finishing floors, walls or ceilings. At this point, the "first-fix" of the central heating system is effected; heating pipes are laid in floor/ceiling voids, or along bare walls (for example in notches or grooves, depending on the wall structure) . The pipes are left bare, that is to say, protruding without connection to radiators etc. When the first fix (including that of other services such as electrical supplies) is completed, floors, ceilings and walls are finished. That is to- say, floor boards are laid and plastering of walls is effected. Then, in the second-fix, the exposed pipes are connected to radiators and to the boiler and water supply to complete the system.

Of course, at the time of the second-fix, it is too late to discover that there is a leak in a joint of the pipes under the- floor or in the wall. So the plumber installing the pipework at the first-fix stage must be completely satisfied that the system is leakproof before the floors are laid and walls plastered. This can only be assured by pressure testing. Normally, the plumber connects flow and return pipes together at each radiator location using spare hose and clips, and fills the system with water prior to pressure testing. This is a cumbersome and time consuming task.

It is an object of the present invention to provide a method, and certain apparatus useful for putting the method into effect, that solves the aforementioned problem, or at least mitigates their effects.

In accordance with the present invention there is provided a method of installing a central heating system in a new-build structure comprising the steps of: providing the skeleton of the structure; laying a composite pipe, which pipe includes an integral flow and return path, from a boiler position in the skeleton to a first of a plurality of radiator positions; laying said pipe from the first radiator position to a second and subsequent radiator positions in series; providing a radiator fitting at each radiator position, each radiator fitting having first and second connector ends, and a bridge between them, wherein said connector ends have flow and return through-paths and means for connection to said composite pipe and to said bridge, one connector end having a capped branch forming a flow branch in communication with the flow path of the connector end and the other connector end having a capped branch forming a return branch in communication with the return path of the connector end, and wherein said bridge has flow and return passages and is of such length that the flow and return branches are separated by a distance corresponding with the distance between inlet/outlet fittings on a radiator for which the radiator fitting is intended; providing an end-stop valve having at least closed and open positions on the end of the composite pipe or on the connector end of a last fitting, wherein the closed position seals the flow and return paths of the composite pipe or connector end with respect to one another, and the open position permits fluid communication between the flow and return paths of the composite pipe or connector end; opening said end stop valve; filling the flow and return paths of the composite pipe with liquid and pressure-testing for leaks in the composite pipe and radiator fittings; ^■ completing build of the structure; removing said caps of the flow and return branches at the radiator fittings; and connecting radiators to said flow and return branches .

Preferably, said completing the build of the structure includes concealing parts of said composite pipe behind wallboard fixed to walls of the structure, said branches protruding substantially horizontally through holes in said wallboard.

Preferably, said radiator fitting is a single integral

^■component. Preferably said branches are capped with caps that are no greater in diameter than the diameter of the branches. Preferably, said radiator fitting is of moulded/extruded plastics material. Said caps may be integrally formed plastics plugs.

In another aspect, the present invention provides a radiator fitting comprising an integral component including: a composite pipe having flow and return paths; branches at a preset distance along the composite pipe corresponding with the separation of inlet/outlet fittings on a radiator for which the radiator fitting is intended; one branch forming a flow branch in communication with the flow path of the composite pipe branch forming a return branch in communication with the return path of the composite pipe; each branch being capped and extending substantially perpendicularly with respect to the composite pipe and substantially parallel with respect to each other; and a fixing plate connected to the composite pipe by means of which the radiator fitting may be fixed to a substrate with the composite pipe flush against the substrate and said branches extending substantially perpendicularly thereto.

Preferably, said fixing plate is provided with a centre mark which is central between said branches.

Thus the present invention provides a simple method of installing central heating plumbing in a house during its construction. The composite pipe is laid from the boiler to each radiator position in turn, up to the last, which is then terminated with an end stop. At each radiator position a dedicated radiator fixing is connected to the wall, the centre mark identifying where the centre of the radiator will eventually be sited, and the separation between the branches determining the size . of the radiator subsequently to be fitted.

Testing for leaks is simply effected, since the branches are provided with cap seals, whereby it is only necessary to provide the end-stop valve at one end, to open it, and then to connect the water supply for testing purposes at the boiler end of the composite pipe. Once any leaks have been eliminated, build of the house can be completed with the composite pipe being concealed behind plasterboard or other wall board attached to the wall, leaving only the branches protruding through the wall board. Some of the composite pipe can be concealed under the floors. Indeed, the branches can protrude through the floors, although fixing of the radiator fitting is complicated by this alternative. Either notches need to be cut in joists, where the floor joists are transverse the wall to which a radiator will ultimately be fixed, or special platforms have to be provided, where the joists are parallel to the wall, on which to seat the radiator fitting. Once testing is completed, the end stop valve is closed so that, when the radiators are connected to the branches, (which are of course opened in the process) the end stop valve does not provide a shunt reducing flow through the radiators.

Although it is feasible that a house may have one feed from a boiler to all the radiators in the house, this is likely to leave the last radiator, if there are many of them, with only lukewarm heat. It is most likely in a multi-storey house for one composite pipe to supply all the radiators on a single floor, so that there are, in effect, two composite pipes (in a two-storey house) from the boiler, one supplying upstairs and the other downstairs. This is especially efficient if two areas of the house (eg upstairs and downstairs) , are on different temperature control circuits, whereby it may be desirable from time to time that supply to an entire area be cutoff.

Indeed, the invention also provides an end-stop valve in combination with a multilumen pipe, comprising connection means for sealing connection to an end of said pipe and valve means selectively to seal the lumens with respect to one another and to permit fluid communication between them.

Said pipe may be circular in external section. It may- comprise concentric lumens. Said connection means may comprise a compression fitting. Said end-stop valve may comprise a housing and said valve means may comprise a valve member in the housing actuatable by a screw- threaded rod extending through a threaded bore through the housing and accessible from outside the housing to drive said valve member away from or towards said end of the pipe. Said valve member may be sealed in the housing. Said valve member may slide in a cylindrical bore of the housing and be provided with an 0-ring seal to seal against said bore.

The invention is further described hereinafter, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a current layout of central heating to upstairs radiators from a boiler;

Figure 2 is a layout according to the present invention;

Figures 3a and b are a side section and a cross section on the line B-B in Figure 3a, respectively, through a radiator fitting in accordance with the invention;

Figure 4 is a side section through a boiler fitting; Figures 5a and b are a side section and an end view in the direction of the arrow A in Figure 5a, of a fitting;

Figure 6a is a side section through a T-flow-outlet in accordance with the invention, Figure 6b being schematic illustration of a T-return-inlet;

Figures 7a, b and c are views of a radiator fitting in accordance with the invention, being an alternative embodiment of that shown in Figure 3a and b, and respectively being: a plan view; a section along the line B-B in Figure 7a; and a section along the line C-C in Figure 7a; and, Figures 8a and b are sections through the end of a composite pipe having and end-stop valve, in open and closed positions respectively.

In Figure 1, a prior art system 10 is shown. The first floor 12 of a domestic building has radiators 14a, b,c and d distributed in different rooms (not shown) to provide space heating. The radiators are supplied by a boiler 16 provided with a pump (not shown) that pumps hot water along a common main flow pipe 18 to a central distribution manifold 20. From there, distribution flow pipes 18a, b and d radiate* outwardly to each radiator, possibly with a further junction 22 before all radiators are reached. After flowing through each radiator and shedding heat, a cooler return flow through distribution return pipes 24a, b and d returns the water to manifold 20, and thence via main return pipe 24 to the boiler for reheating. Manifold 20 may consist of simple T-fittings at appropriate junctions of the pipes 18,24. Pipes 18,24 will be sized to accommodate the required flow, so that different pipes are needed, and calculations must be made to determine the appropriate size.

In contrast, the present invention provides a system 100 shown in Figure 2. Here the boiler 16 is as before, but flow and return pipes 18,24 lead directly into a boiler fitting 30in accordance with the present invention. Boiler fitting 30 is shown in more detail in Figure 4, where a body 32 has an inlet 34a and outlet 34b for connection to the main -flow and return pipes 18,24 respectively. Inlet 34a proceeds uninterrupted to flow pipe outlet 36a of a composite port 36. Outlet 34b, on the other hand, opens into body 32. Body 32 also leads to port 36, but as return pipe inlet 36b concentrically around flow pipe outlet 36a. Spider 38 retains outlet 36a concentric with inlet 36b.

Returning to Figure 2, a composite main flow/return pipe 40 is connected to port 36 of boiler fitting 30 and is led to first radiator 14d, which is also conventional. However, beneath the radiator is a radiator fitting 50, shown in more detail in Figures 3a and b.

Fitting 50 is sized according to standard radiator sizes. It has a flow outlet 52 and return inlet 54 separated by a distance depending on the distance between the fittings of the- radiator. These are standard for many makes of' radiator.

Flow outlet 52 connects to an internal conduit 56 of the fitting 50, whereas inlet 54 connects to an external, annular conduit 58 concentric with the conduit 56. Thus, hot water flow in the inner conduit 56 exits through outlet 52 to enter the radiator 12d where it sheds heat before exiting the radiator and entering inlet 54 of the fitting 50. There it joins cool water return in outer conduit 58.

Indeed, main flow/return pipe 40 has the same construction as the fitting 50 between the ports 52,54, and in cross section may be identical to the section shown in Figure 3b. Pipe 40 is conveniently constructed from plastics material. It may comprise a web 42 that joins the outside of conduit 56 to the inside of conduit 58. The pipe i-s then extrudable. Likewise a barrier layer (not shown) of aluminium or the like may surround conduit 58 to prevent the passage through the pipe wall of gas such as oxygen. Of course, the flow conduit 56 needs no such barrier, since that is provided by the barrier around return conduit 58.

Main flow/return pipe 40 joins fitting 50 at one end thereof. Figure 5a shows one potential arrangement, comprising a connector 60. This has an inner through conduit 62, and outer conduit 64. Inner conduit 62 has seals 66 at its end for sealing against the internal bore of conduit 56 of the fitting 60. Likewise it does the same to a pipe 40 (not shown) connected to its other end. Outer conduit 64 is provided with sealing and clamping flange 68. This serves both to seal and connect to the external surface of conduit 58.

Connector 60 likewise has webs 42' to retain inner connector 62 concentric with the outer connector, and also to fix it axially. It is not imperative that there is a perfect seal between the inner and outer conduits 56,58, although any leakage does waste energy. Therefore the joints between inner connector 62 and inner conduit 56 of either the fitting or pipe do not have to be secure. However, it is only the connection between outer connector 64 and outer conduit 58 that retains the inner connection 62/56 in place. Moreover, it is only the webs 42' that drive the inner connection 62/56 when the outer connection 64/58 is being made; at least, that is the case when the second end of the two ends of the connector 60 is being connected to the other of the pipe 40 and fitting 50.

While Figure 5a shows a connector 60, it is possible to provide the fitting 50 itself directly with the connector end 70 represented by the connector 60. A separate connector 60 can then be avoided.

Although fitting 50 is shown as a^' bespoke fitting, it can be constructed from pipe 40 using two fittings 80a,b shown in Figures 6a and b.

Fitting 80a corresponds with connector 60, except here a branch 82a, b is formed, in one case (fitting 80a, Figure 6a) from the inner conduit 62', and in the other case (fitting 80b, Figure 6b) from the outer conduit 64". A pipe 40 (not shown) cut to the right length for the radiator, can be connected between two fittings 80a,b to form an equivalent construction of the radiator fitting 50.

Returning once more to Figure 2, pipe 40 extends from the remote end 54 of fitting 50 to the next radiator 14a, where the arrangement is repeated, and so on to the last radiator 14c.

The present invention enables a house or other dwelling to be constructed in a convenient manner, at least insofar as installation of a central heating system is concerned. Construction of any such building requires installation of plumbing and other services to be effected once the skeleton of the house has been constructed. Whether this involves a timber frame or block wall construction, prior to final surfacing of floors, walls and ceilings, plumbing pipes, electrical wiring and other installations need to be laid. Increasingly it is not acceptable to notch floor joists, and it is difficult, and not especially desirable to drill them. In any event, drillings are only permitted at locations spaced from the ends of joists. The practice now frequently adopted is to dispose services against a wall, but behind a final plaster or other board. Notching, or drilling, of wall members is not seen as detrimental to the structure.

Once plumbing pipelines have been installed, it is necessary to test the runs to ensure there are, or will be, no leaks once the system is operational. The present invention is convenient in this respect because a single composite pipe is led from the anticipated boiler location to each radiator position in turn. At least part of this run of pipes can be against a wall and the radiator fitting 50' shown in Figure 7a has an integral back plate 90 provided with fixing eyes 92. These can be employed to fix the fitting 50' to a block wall 94, in a notch 96, for example, using screws 98 (see Figure 7b) . Alternatively, in a timber frame house, or where stud- walls are disposed, the notch 96' may be in vertical studs 94' (see Figure 7c) and the fixing is by nails 98' .

The radiator fitting 50' is shown as an unit, but it could be constructed from a length of composite pipe and two T-fittings such as shown in Figures 6a and b. Thus the fitting 50' should be regarded as comprising two end connectors (or connector regions) A, B, and an intervening bridge section or region C. Whether these are independent components fitted together on site, or integrally formed units, as shown, is not material to the mode of operation. Nevertheless, it is one aspect of the invention that a series of bespoke fittings 50' of different branch separation (d) are made available suited to typical radiator sizes. Each end connector A, B has means 122 for connection to a composite pipe. Such means may simply comprise a form of construction identical to the composite pipe itself, so that straight connectors 60 such as illustrated in Figure 5a, can connect a composite pipe to the end connectors A, B. However, as mentioned above, they could also be formed with the end 70 of connector 60.

In any event, referring again to Figures 7a, and c, the wall is subsequently finished with wall board 110, fixed by dot-and-dab plaster 112, in the case of block walls 94, or screws 112' in the case of stud walls 94' . The wall board is cut with holes 114 to allow passage, horizontally, of flow and return branches 52', 54' of the fitting 50'. To facilitate location of the fitting 50', it is provided with centre marks 116, so that it is straightforward, to align with the centre of a window opening (not shown), for example.

The branches 52', 54' are sealed at their ends by caps 118. These should be no larger in diameter than the branches themselves, so that they pass through the holes 114 without difficulty. Ideally, they are integrally formed with the branch, for example by moulding, prior to connection of the branch to the fitting 50' . In any event, they need to be capable of withstanding test pressures .

To test the system, an end stop valve 120 (see Figures 8a and b) is employed adjacent the last radiator (see also Figure 2) . Valve 120 comprises a housing 122 having a sleeve connector 124 to permit connection on the end of a composite pipe 40. A valve seat 126 is disposed on the end of a screw shank 128, operable with an appropriate tool such as a spanner or screwdriver, to drive the valve seat left and right in the drawings through a screw- threaded bore 130 formed in the housing 122. In the ^•position shown in Figure 8a, the valve is open, so that fluid communication exists between the flow and return conduits 56,58 of the pipe 50. At this stage, the boiler 16 will not have been fitted, but one of the conduits 56,58 (or ports 18,24 of the boiler fitting 30 if that is fitted - see Figure 4) is connected to a liquid supply such as mains water. The water then flows along the conduit 56 or 58 and reaches the end-stop valve 120. The water then returns along the other of the conduits 56,58 until it evolves from the fitting 30. When this occurs, one of the ports 18,24 is closed and the other port is connected to a source capable of applying a pressure in the system of the order of 10 bar, or such other pressure as adequately tests that the various joints in the system are leak proof and secure.

Once tested and found .satisfactory, the second stage of the building can be completed with floor, wall and ceiling coverings being applied. Finally, the caps 118 are removed from the branches 52', 54', for example by employing a pipe cutter (not shown) , and the lockshield or other radiator valves (also not shown) are connected directly to them to connect radiators (not shown) that match the radiator fitting 50' . Then, the end stop valve 120 is actuated to close the end of the composite pipe 40 and prevent further communication between the conduits 56,58. When a boiler 16 is connected, as described above, the system is rendered operational.

Claims

1. A method of installing a central heating system in a new-build structure comprising the steps of: providing the skeleton of the structure; laying a composite pipe, which pipe includes an integral flow and return path, from a boiler position in the skeleton to a first of a plurality of radiator positions; laying said pipe from the first radiator position to a second and subsequent radiator positions in series; providing a radiator fitting at each radiator position, each radiator fitting having first and second connector ends, and a bridge between them, wherein said connector ends have flow and return through paths and means for connection to said composite pipe and to said bridge, one connector end having a capped branch forming a flow branch in communication with the flow path of the connector end and the other connector end having a capped branch forming a return branch in communication ■ with the return path of the connector end, and wherein said bridge has flow and return passages and is of such length that the flow and return branches are separated by a distance corresponding with the distance between inlet/outlet fittings on a radiator for which the radiator fitting is intended; providing an end-stop valve having at least closed and open positions on the end of the composite pipe or on the connector end of a last fitting, wherein the closed position seals the flow and return paths of the composite pipe or connector end with respect to one another, and the open position permits fluid communication between the flow and return paths of the composite pipe or connector end; opening said end stop valve; filling the flow and return paths of the composite pipe with liquid and pressurising to test for leaks in the composite pipe and radiator fittings; completing build of the structure; removing said caps of the flow and return branches at the radiator fittings; and connecting radiators to said flow and return branches .

2. A method as claimed in claim 1, in which said completing the build of the structure includes concealing parts of said composite pipe behind wallboard fixed to walls of the structure, said branches protruding substantially horizontally through holes in said wallboard.

3. ^'A method as claimed in claim 1 or 2, in which said radiator fitting is an integral component.

4. A method as claimed in claim 1, 2 or 3, in which said branches are capped with caps that are no greater in diameter than the diameter of the branches.

5. A method as claimed in any preceding claim, in which said radiator fitting is of moulded/extruded plastics material.

6. A method as claimed in claims 4 and 5, in which said caps are integrally formed plastics plugs.

7. A radiator fitting comprising an integral component including: a composite pipe forming a bridge and having flow and return paths; branches at a preset distance along the composite pipe corresponding with the separation of inlet/outlet fittings on a radiator for which the radiator fitting is • intended; one branch forming a flow branch in communication with the flow path of the composite pipe branch forming a return branch in communication with the return path of the composite pipe; each branch being capped and extending substantially perpendicularly with respect to the composite pipe and substantially parallel with respect to each other; and a fixing plate connected to the composite pipe by means of which the radiator fitting may be fixed to a substrate with the composite pipe flush against the substrate and said branches extending substantially perpendicularly thereto.

8. A radiator fitting as claimed in claim 7, in which said fixing plate is provided with a centre mark which is central between said branches.

9. A central heating system comprising a boiler for heating a heat transfer fluid, means flowing the heated fluid to radiators distributed around an area to be heated, and means returning the fluid once it has released some of its heat to the radiator, wherein said means flowing the heated fluid is contained within said means returning the fluid between the boiler and at least a first radiator and/or between radiators; and wherein said means flowing and returning comprises a radiator fitting as claimed in claim 7 or 8.

10. .A system as claimed in claim 9, in which said combined flow and return to and from the boiler is on a single route to each radiator in turn.

11. A system as claimed in claim 9 or 10, in which said means flowing and returning comprises a composite pipe having an inner lumen for said flow and an outer, surrounding, lumen for said return.

12. A. system as claimed in claim 11, in which said pipe is a plastics extrusion of an inner conduit concentric with an outer conduit and joined thereto by a web.

13. A system as claimed in claim 12, in which said outer conduit is provided with a gas barrier.

.

14. A system as claimed in claim 13, in which said gas barrier is an aluminium envelope. <

15. A system as claimed in any of claims 11 to 14, further comprising a fitting to join to said composite pipe, comprising an inner connector having seals on an outer annulus thereof to seal against the bore of the inner conduit of the pipe, and an outer connector to both seal and clamp the outer conduit of said composite pipe.

16. A system as claimed in claim 15, in which said seal and clamp are both against an outer surface of the outer conduit.

17. A system as claimed in any of claims 8 to 16, in which a boiler fitting comprises a body having an inlet and an outlet for connection to flow and return pipes of a boiler, the inlet passing through the body to a flow outlet of a composite port and said outlet opening into a space in said body connecting with an annular inlet of said composite port surrounding said outlet.

18. A system as claimed in claim 11 or any of claims 12 to 17 when dependent on claim 11, in which said pipe is a plasties extrusion of an inner conduit concentric with an outer conduit and joined thereto by a web.

19. A system as claimed in claim 18, in which said outer conduit is provided with a gas barrier.

20. A system as claimed in claim 19, in which said gas barrier is an aluminium envelope.

21. An end-stop valve in combination with a multilumen pipe, comprising connection means for sealing connection to an end of said pipe and valve means selectively to seal the lumens with respect to one another and to permit fluid communication between them.

22. A valve as claimed in claim 21, in which said pipe ' is circular in external section.

23. A valve as claimed in claim 21 or 22, in which said pipe comprises concentric lumens.

24. A valve as claimed in claim 22 and 23, in which said connection means comprises a compression fitting.

25. A valve as claimed in any of claims 21 to 24, in which said end-stop valve comprises a housing and said valve means comprises a valve member in the housing actuatable by a screw-threaded rod extending through a threaded bore through the housing and accessible from outside the housing to drive said valve member away from or towards said end of the pipe.

26. A valve as claimed in claim 25, in which said valve member is sealed in the housing.

27. A valve as claimed in claim 25 or 26, in which said valve member slides in a cylindrical bore of the housing and is provided with an 0-ring seal to seal against said bore.

28. A central heating system, and components thereof, and a method of construction thereof, substantially as hereinbefore described with reference to the drawings.