GB2589551A

GB2589551A - Vent pipe

Info

Publication number: GB2589551A
Application number: GB1914454.2A
Authority: GB
Inventors: John Wragg Richard
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-10-07
Filing date: 2019-10-07
Publication date: 2021-06-09
Anticipated expiration: 2039-10-07
Also published as: GB2589551B; GB201914454D0

Abstract

A vent pipe 100 for a heating system, comprising a pipe section 102 having a first end 104 and a second end 106, the pipe section having at least one aperture 108 at or near the first end; a cowl 110 extending around the first end of the pipe section, the cowl being open in a direction away from the first end of the pipe section so that, in use, fluid flowing along the pipe section and exiting through the at least one aperture will impinge upon the cowl and thereby be deflected at least partially in a direction back along the pipe section away from the first end of the pipe section; and a seal comprising a resiliently deformable sealing member 120 extending around the pipe section so that, in use, the sealing member forms a seal, the seal being located at a position along the pipe section between the second end and the at least one aperture. A method of installing a vent pipe for a heating system is also disclosed.

Description

VENT PIPE

The present invention relates to vent pipes for heating systems and other similar systems. It has applications in domestic central heating systems as well as heating systems for industrial applications, but could equally be used in any system which includes a vent pipe that acts as a blow-off vent for venting fluid, either liquid or gas, under pressure, or may be used with an over flow outlet of other types of system.

Blow-off vents are provided for central heating systems so allow hot air and steam to escape through an external wall of the building in which the system is installed.

Known types of blow-off vent include a vent pipe section that extends through an external wall and terminates outside of the building. In order to prevent hot air or steam from being ejected outwards from the wall it is known to fit a cowl to direct the escaping fluid back towards the wall. The cowl may be secured to the end of the vent pipe section directly. In other examples, the cowl may be fixed to a separate section of pipe to form a pipe cowl fitting that can be soldered onto the open end of the vent pipe protruding from the outer surface of the wall. The cowl extends around the end of the pipe with its open end facing towards the wall. Steam or hot air escaping from apertures in the pipe impinges on the inside surface of the cowl and is directed at least partially back towards the wall. Once the vent pipe has been fitted the space between it and the hole through which it extends is sealed with a suitable sealant. This is required to prevent any water ingress into the hole causing damage to the wall.

A drawback of the blow-off vents described above is that the attachment of the cowl and sealing of the space around the pipe must bc performed from outside of the building. To install the vent pipe, a hole is drilled through the wall from the inside of the building and a section of pipe to form the vent pipe pushed through from the inside. An installer must then find the protruding end of the pipe, fit the cowl and seal the hole. Alternatively, a longer length of pipe with a cowl attached can be pushed through a pre-drilled hole from the outside of the building. Fitting the cowl from outside the building in this way can be a problem where the vent pipe is installed high off the ground (e.g. in a high rise building) where access is difficult. Even where the vent pipe is installed close to ground level access can still be difficult, for example if the external wall is close to another structure or building limiting the access space in which the installer can work. Coupling of the pipe cowl fitting to the end of the pipe during installation can also be problematic as it is time consuming and the joint has the potential to leak. Moreover, if the part of the pipe having the joint is pushed back within the wall it can be inaccessible and difficult to repair.

A general problem to be addressed therefore is how to install a blow-off vent for a central heating system from the inside of a building so that external access is not required.

In a first aspect, the present invention provides a vent pipe for a heating system, comprising: a pipe section having a first end and a second end, the pipe section having at least one aperture at or near the first end; a cowl extending around the first end of the pipe section, the cowl being open in a direction away from the first end of the pipe section so that, in use, fluid flowing along the pipe section and exiting through the at least one aperture will impinge upon the cowl and thereby be deflected at least partially in a direction back along the pipe section away from the first end of the pipe section; and a seal comprising a resiliently deformable sealing member extending around the pipc scction so that, in use, thc scaling member forms a seal, the seal being located at a position along the pipe section between the second end and the at least one aperture.

The vent pipe of the present invention includes a resiliently deforniable sealing member that allows it to be installed from the inside of a building without requiring any external access. The resiliently deformable scaling member can be deformed such that it can be inserted through a hole in a wall. It then returns to its original size and shape once it is pushed clear of the hole. Once in its original size and shape the sealing member can form a sealing contact with the outside surface of the wall to seal the hole, without requiring any external access.

The vent pipe of the present application provides a number of environmental advantages. By avoiding the need to assemble multiple parts of the vent pipe from the outside of the building the number of parts and material from which it is produced is reduced. The need to connect parts together by soldering can also be reduced.

The seal may seal a hole in a wall through which the pipe section extends when the vent pipe is in use. The sealing member may extend substantially all of the way around the pipe section to seal the hole through which the vent pipe extends when in use. The sealing member may se& the hole by sealing against the outer surface of the wall, or may remain at least partly inside the hole to act as a plug. The sealing member therefore extends around the vent pipe to an extent sufficient to seal the hole. This may mean extending completely around the vent pipe so that the vent pipe is surrounded.

The sealing member may be annular and extend all of the way around an outer surface of the pipe section. This may allow the sealing member to form a sealing surface which may seal against the outer surface of the wall to seal the hole The sealing member may be formed at least partly from a resiliently deformable material. The resiliently deformable material may be rubber. This may allow the sealing member to be efficient and easy to manufacture. it may, for example, be formed from a rubber washer.

The seal may be arranged so that the sealing member deforms to a greater extent in response to a force acting in a direction along the length of the pipe section towards its second end compared to an equal force acting in the opposite direction along the length of the pipe section (i.e. towards it first end). This may help allow the vent pipe to be inserted through the hole, but resist being extracted in the opposite direction.

The seal may further comprise a first retaining member arranged to limit deformation and/or movement of the sealing member in response to a force acting in a direction along the length of the pipe section towards its first end. The first retaining member may therefore prevent (or make it difficult) to retract the vent pipe from the hole by moving it in a direction opposite to the direction in which it was inserted (i.e after being inserted first end first).

The first retaining member may extend from, and at least partly around, an outer surface of the pipe section, thereby forming a first retaining surface arranged to limit deformation and/or movement of the sealing member.

The cowl may extend radially from the longitudinal axis of the pipe section a distance less than or equal to the first retaining member. This allows the hole to be sized to allow both of the cowl and first retaining member to pass through.

The seal may further comprise a second retaining member arranged to limit deformation and/or movement of the sealing member in response to a force in a direction along the length of the pipe section towards its second end. This may resist or prevent the sealing member from being displaced along the length of the pipe section when the vent pipe is inserted through a hole, cowl or first end first.

The second retaining member may extend from, and at least partly around, the outer surface of the pipe section, thereby forming a second retaining surface arranged to limit deformation and/or movement of the sealing member.

The first retaining member may extend radially from the longitudinal axis of the pipe section a greater distance than the second retaining member. This allows the retaining members to provide a greater resistance to deformation of the sealing member in response to a force in one axial direction along the pipe section compared to the opposite axial direction along the pipe section.

The pipe section may be formed from an integral length of pipe extending between the first end and the second end. This may avoid the need to have any joins along its length which could be susceptible to leaking. More specifically, this may avoid the need to have any such joins located within the thickness of the wall where they cannot be repaired.

The fluid directed by the cowl may be incident on a spray area, the spray area being defined in a plane normal to the longitudinal axis of the pipe section at a position level with a sealing surface of the sealing member (or a plane normal to the longitudinal axis of the pipe section at a position level with the surface of a wall through which the pipe section extends, e.g. if the seal is absent). The spray area may have a cross sectional size less than or equal to 52 mm. This has been found to provide a suitable sized spray area that does not cover too much of the wall.

The spray area may have a cross sectional size in the range between 40 mm and 50 mm. This has been found to allow a suitable balance of spray area size while allowing a convenient size of cowl that is not too difficult to manufacture and not too unattractive. Preferably, the spray area has a cross section& size equal to 50 mm. This has been found to provide an optimal balance of spray area size and associated cowl size.

The cowl may have an inner concave surface arranged to direct the fluid, the concave surface being bounded by an outer edge. A cowl size may be defined as the greatest distance B across the concave inner surface between two points on the outer edge. The cowl size may be in a range between 24 mm and 26 mm. This has been found to help provide a suitable range of spray area size. Preferably the cowl size is equal to 24 mm. This has been found to help provide an optimal size of spray area.

A cowl separation distance may be defined as the axial distance between the outer edge of the concave inner surface and the plane normal to the longitudinal axis of the pipe section at a position level with the sealing surface of the sealing member (or the plane normal to the longitudinal axis of the pipe section at a position level with the surface of the wall through which the pipe section extends e.g. if the seal is absent).

The cowl separation distance may be in the range between 6 mm and 8 mm. This has been found to help provide a suitable range of spray area size. Preferably the cowl separation distance is equal to 8 mm. This has been found to help provide an optimal size of spray area.

A cowl wall angle may be defined as the angle extending between a plane tangential to the concave inner surface at a point on its outer edge and a plane normal to the longitudinal axis of the pipe section. The cowl wall angle may be in the range between 28 degrees and 30 degrees. This has been found to help provide a suitable range of spray area size. Preferably the cowl wall angle is equal to 30 degrees. This has been found to help provide an optimal size of spray area In a second aspect, the present invention provides a method of installing the vent pipe of the first aspect, the method comprising: inserting the first end of the vent pipe through a hole in a wall from a first side of the wall such that the cowl and seal protrude from a second side of the wall; retracting the vent pipe until the seal forms a sealing contact with the surface of the second side of the wall.

In a third aspect, the present invention provides a vent pipe comprising: a pipe section having a first end and a second end, the pipe section having at least one aperture at or near the first end; and a cowl extending around the first end of the pipe section, the cowl being open in a direction away from the first end of the pipe section so that, in use, fluid flowing along the pipe section and exiting through the at least one aperture will impinge upon the cowl and thereby be deflected at least partially in a direction back along the pipe section away from the first end of the pipe section, wherein: the fluid directed by the cowl is incident on a spay area, the spray area being defined in a plane normal to the longitudinal axis of the pipe section at a position level with the surface of a wall through which the pipe section extends; and the spray area has a cross sectional size less than or equal to 52 mm.

Any of the statements above may be combined with the first, second or third aspect.

As used herein, a range "from value X to value Y" or "between value X and value Y", or the like, denotes an inclusive range; including the bounding values of X and Y. Embodiments of the various aspects of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a side view of a vent pipe; Figure 2 shows a close-up side view of the vent pipe shown in Figure 1; Figure 3 is an exploded side view showing various components of the vent pipe shown in Figure I; Figures 4 to 6 show the vent pipe shown in Figure 1 being installed through a hole in a wall; Figure 7 shows a side view of the vent pipe of Figure 1 illustrating its spray area; Figure 8 shows a front view corresponding to the view of Figure 7; Figure 9 shows the vent pipe of Figure I coupled to the boiler of a heating system; and Figure 10 illustrates a method of installing the vent pipe.

A vent pipe 100 is illustrated in Figures 1 and 2, with an exploded view of various components of the vent pipe 100 shown in Figure 3 The vent pipe 100 comprises a pipe section 102, one or more apertures 108, a cowl 110 and a seal 118. As shown in Figure I, the pipe section 102 extends between a first end 104 and a second end 106. The pipe section is generally straight and of circular cross section and is suitable for carrying fluid such as steam or hot gas vented from a heating system. In the presently described embodiment, the pipe section and cowl are formed from copper. In other embodiments however, other materials may be used such as polymeric materials.

The pipe section 102 has three apertures 108 at the first end 104 (only two of which arc visible in the Figurcs). The apertures arc defined in the side of the pipe section 102 as can be seen in Figure 2, and are in the form of cut-outs extending along the pipe section from its first end 104. The apertures 108 are arranged to allow fluid flowing along the pipe section 102 to escape from the vent pipe 100. In the presently described embodiment three apertures are provided, whereas in other embodiments any other number of apertures may be provided. The apertures may take a different form from that shown in Figures 1 and 2. For example, the apertures may be formed by slots extending longitudinally along the pipe section 102. The apertures may therefore be spaced apart from the first end 104 of the pipe section 102 (i.e. are near to, rather than extending from, the first end 104).

The vent pipe 100 comprises a cowl 110 extending around the first end 104 of the pipe section 102. The cowl 110 is open in a direction away from the first end 104 of the pipe section 102 so that, in use, fluid flowing along the pipe section and exiting through the apertures 108 will impinge upon the cowl. The fluid is thereby deflected at least partially in a direction back along the pipe section 102 away from its first end 104 (as illustrated by the arrows in Figure 2). The cowl has a concave inner surface 112 which is shaped to direct fluid escaping from the apertures 108. This prevents the fluid from being ejected outwards from a wall through which the vent pipe 100 passes, and thereby provides protection, for example, for people standing or walking by the wall.

The cowl 110 generally has the form of a frustum, and in the presently described embodiment is part-conical or frustoconical in shape. Referring to Figure 3, the cowl 110 has a circular flat portion 114 at its centre which fits over the first end 104 of the pipe section 102. Around the flat portion 114 is an angled wall portion 116 that is arranged to direct the fluid outwards and backwards away from the first end of the pipe 104. The cowl 110 is secured to the first end 104 of the pipe section 102 by brazing. In other embodiments, other couplings between the cowl 110 and the pipe section 102 may be provided. For example, supporting limbs may be formed by tabs cut-out from the wall of the pipe section. In this example, the tabs are bent outwards from the surface of the pipe section 102 to both form the apertures and supporting limbs for the cowl.

The shape of the cowl illustrated in the Figures is only one such example. In other embodiments, the cowl may be domed or dished, rather than being part conical in shape. In yet other embodiments, the cowl may be fully, rather than partly, conical in shape. The cowl may be as described in GB2396204.

The second end of the pipe section 102 is open and can be coupled to another pipe or fitting forming part of a pressure relief outlet or blow-off vent of a heating system. In some embodiments, a channel containing a solder ring is provided at or near the second end 106 of the pipe section for attaching it to another length of pipe. In other embodiments, the pipe section may be attached to the pressure relief outlet using any other suitable coupling or connection The vent pipe 100 is provided with a seal 118 which comprises a resiliently deformable sealing member 120. The seal is located at a position along the length of the pipe section 102 between its second end 106 and the apertures 108. The sealing member 120 forms a sealing surface 120a by which the seal 11/1 seals against the outer surface of the wall. in the present embodiment, the seal is adjacent the apertures 108, but may in other embodiments be spaced further from the apertures so that the apertures are mounted further from the wall through which the vent pipe extends.

In use the vent pipe 100 is inserted in to a hole in a wall by moving it in an insertion direction (illustrated in Figure 4) so that the cowl is inserted into the hole from a first side of the wall (e.g. the interior side). The sealing member 120 deforms when it is inside the hole so that it can pass therethrough. The vent pipe is moved in the insertion direction until the sealing member is outside of the hole on a second (e.g. exterior) side of the wall (illustrated in Figure 5). The vent pipe is then moved in a retraction direction, which is a direction opposite to the insertion direction, so that the sealing member contacts the outer surface of the second side of the wall. The sealing member 120 extends, when the vent pipe is installed, over the hole through which the vent pipe 100 passes (as illustrated in Figure 6) so that the hole is sealed. This reduces water ingress into the hole through the gap between the pipe section 102 and the inner surface of the hole.

Referring again to Figures I to 3, the sealing member 120 extends around the outer surface of the vent pipe 102. The sealing member 120 also extends in a direction radially outward from the longitudinal axis X of the vent pipe 102 to form the scaling surface 120a which provides a sealing engagement with the wall 204. In the presently described embodiment, the sealing member 120 is annular in shape and so extends all of the way around the vent pipe 102. In other embodiments, other shaped sealing members 120 may be provided that extend substantially around the pipe section sufficiently to create a suitable sealing surface 120a to seal a hole through which the vent pipe extends when it is in use.

The sealing member 120 extends radially from the axis X to an extent greater than the cowl 110 (when the sealing member 120 is not deformed). This allows the cowl 110 to be passed through the hole, while still allowing the sealing member to cover the hole and provide a seal.

The sealing member 120 is formed at least partly from a resiliently deformable material. In the presently described embodiment, the sealing member 120 is formed from rubber. Other suitable resiliently deformable materials may however be used.

The seal 118 further comprises first and second retaining members 122, 124. The retaining members 122, 124 are arranged to limit deformation and/or movement of the sealing member 120 in a respective direction along the axial length of the pipe section 102. Each retaining member 122, 124 extends from, and at least partly around, the outer surface of the pipe section 102, to form a respective retaining surface 122a, 124b arranged to limit the deformation and/or movement of the sealing member 120.

The first retaining member 122 is located adjacent the sealing member 120 between the sealing member 120 and the first end 104 of the pipe section 102. its retaining surface 122a therefore engages with the sealing member 120 to resist or limit its movement or deformation in a direction towards the first end 104 of the pipe section. In other words, the first retaining member 122 is arranged to resist movement of the sealing member 120, or limit its degree of deformation, in response to a force applied to the sealing member at least partly in an axial direction of the pipe section 102 towards its first end 104 (e.g. resulting from moving the pipe in the retraction direction). By limiting the deformation of the sealing member 120 in this way, it is prevented from deforming (or is difficult to deform) when moved in the retraction dircction. This means that the vent pipe 100 is difficult to, or cannot be, extracted (by moving it in the retraction direction) from the hole once it has been inserted.

The second retaining member 124 is located adjacent the sealing member 120 between the sealing member 120 and the second end 106 of the pipe section 102. It is therefore on the opposite side of the sealing member 120 to the first retaining member 122. The retaining surface 124a of the second retaining member 124 engages with the sealing member 120 to resist or limit its movement or deformation in a direction towards the second end 106 of the pipe section (i.e, in response to a force acting along the length of the pipe section toward the second end such as that resulting from inserting the vent pipe through a hole, cowl first). This may help to prevent the sealing member from sliding along the pipe section 102 when it is pushed through the hole by being moved in the insertion direction In the presently described embodiment, the first and second retaining members 122, 124 are each formed by a flange extending all of the way around the circumference of the vent pipe 102. As can be seen in Figure 3, the flange is formed on a tubular member by which it is coupled to the outer surface of the pipe section. A friction fit is provided between each of the retaining members 122, 124 and the outer surface of the pipe section 102 to hold them in place. The friction fit may be strengthened by forming dimples in the retaining member once it is in place around the pipe section 102. Other methods of attaching the retaining members 122, 124 may however be used, such as adhesive or brazing. in other embodiments, the retaining members 122, 124 may be integral with the pipe section 102, rather than being formed from separate components. The shape of the retaining members shown in Figures 1 to 3 is only one example, with other shapes being possible such that suitable retaining surfaces 122a, 124a are formed. For example, the retaining members 122, 124 may not extend all of the way around the circumference of the pipe section 102 The first retaining member 122 is arranged to limit the degree of deformation of the sealing member 120 to a greater extent than the second retaining member 124. This allows the sealing member 120 to be pushed through the wall by moving it in the insertion direction, but resists or prevents the vent pipe from being retracted by moving it in the retraction direction. This allows the sealing member 120 to be pulled against the external surface of the wall to form a seal. In order to allow the sealing member 120 to deform more easily in one direction along the pipe section than the other, the first retaining member 122 extends radially from the longitudinal axis X of the pipe section a greater distance than the second retaining member 124. In the present embodiment, the first retaining member 122 therefore has a diameter P shown in Figure 3 that is greater than a diameter Q of the second retaining member 124.

As can be seen in Figures 2, 3 and 6 the diameter S of sealing member 120 in its relaxed or non-deformed state is greater than the diameter]? of the cowl 110 and also greater than the diameters Q, P of both of the retaining members 122, 124. This allows the hole through which the vent pipe 100 is installed to be sized such that the cowl 110 and seal 118 can pass through it, while still allowing a seal to be made once the sealing member 120 returns to its non-deformed state.

The cowl 110 also extends radially from the longitudinal axis X of the pipe section a distance less than or equal to the first retaining member 122. This allows the hole through which the vent pipe is installed to be sized to allow both the cowl 110 and the first retaining member 122 to pass through, while maximising the size of the cowl. in the presently described embodiment the cowl 110 and first retaining member extend radially to approximately the same distance (i.e. they have the same diameter).

In the presently described embodiment, the vent pipe 100 is formed from an integral pipe section 102 that has no joints or connections between the first and second ends 104, 106. This reduces the time taken to install the vent pipe, and avoids the need to have a joint within the thickness of the wall though which the vent pipe is installed. In other embodiments, however, the pipe section 102 may be made up from any suitable number of separate sections of pipe that are connected together via any suitable method such as brazing, soldering or adhesive.

Installation of the vent pipe is illustrated in Figures 4 to 6. In these Figures the vent pipe 100 is installed through a hole 202 in an external wall 204 of a building in which a heating system is located. The wall 204 has an external surface 204a and an internal surface 204b. In Figure 4 the vent pipe can be seen being inserted, cowl first, through the hole 202 from internal side of the wall (i.e. moved in the insertion direction). By providing the seal 118 with a resiliently deformable sealing member 120 it can deform when pushed through the hole as can be seen in Figure 4. This means that the vent pipe 100 can be pushed through a hole in an external wall from the inside until the cowl 110 and the seal 118 protrude from the external surface 204a of the wall as illustrated in Figure 5. The seal 118 deforms whilst inside the hole 202, and then returns to its original shape once it is outside of the hole 202. The vent pipe 100 can then be retracted (by being moved in the retraction direction) so that the sealing member 120 seals against the external surface 204a of the wall and seals the hole as illustrated in Figure 6. The seal 118 is therefore moveable between a deformed configuration in which it is small enough to pass through the hole 202 and a sealing configuration in which a sealing engagement can be formed with the external surface of the wall. The vent pipe 100 can therefore be installed from an internal side of the wall, without needing any external access to attach the cowl or seal around the pipe section 102 once it is installed.

Referring to Figures 7 and 8, fluid escaping from the apertures 108 and directed towards the wall 204 by the cowl 110 is incident on a spray area 302 at the position of the outer surface of wall 204a. The spray area is defined in a plane normal to the longitudinal axis X of the pipe section 102, the plane being level with the sealing surface 120a of the sealing member 120 (this plane is labelled X' in Figure 1). When the vent pipe is installed (or in connection with embodiments in which the seal is absent), the plane over which the spray area is defined may instead be defined in a plane coinciding with the outer surface of the wall 204a (e.g. a plane normal to the longitudinal axis of the pipe section at a position level with the surface of a wall through which the pipe section extends). As can be seen in Figure 7, the extent of the spray area is defined by a tangential path (shown by the dashed arrows) extending from a point on the outer edge 122a of the inner concave surface 122 towards the wall.

The cowl has a shape, size and position relative to the sealing surface 120a (and therefore relative to the wall) such that the largest distance A across the spray area (in the plane X') is less than or equal to 52 mm. More specifically, the largest distance A across the spray area is in a range between 40 mm and 50 mm. Yet even more specifically, the largest distance A across the spray area is equal to 50 mm. In the present embodiment, the spray pattern is circular in shape and is centred on the longitudinal axis X of the pipe section 102 (as can be seen in the front view of Figure 8). In this embodiment, the largest distance A across the spray area is its diameter. Other shapes of spray area may be formed depending on the shape of the cowl.

In order to achieve the desired size of spray area the relative size and shape of the cowl 110 (specifically its inner concave surface) along with the axial distance between the cowl 110 and the sealing member 120 may be adjusted.

The extent of the spray area 302 may depend on one or more of the following factors: a) a cowl size being defined as the greatest distance B across the concave inner surface between two points on its outer edge (i.e. the diameter); b) a cowl separation distance defined as the axial distance C between the outer edge 122a of the concave inner surface 112 of the cowl and the plane X' in which the spray area is defined (or to the outer surface of the wall 204a), and c) a cowl wall angle defined as the angle 0 extending between a plane Y tangential to the concave inner surface 112 at a point on its outer edge 122a and a plane Y' normal to the longitudinal axis X. It has been found that a desired spray area can be provided by a cowl having a cowl size in the range between 24 mm and 26 mm. In the present embodiment, this is combined with a cowl separation distance in the range between 6 mm and 8 mm and a cowl wall angle in the range between 28 degrees and 30 degrees.

More specifically, it has been found that a cowl size of 24 mm is advantageous in providing a suitably sized spray area (e.g. of 50 mm in the present embodiment) while ensuring the cowl is easy to install and manufacture, and is not too visually unattractive. In the present embodiment, this is combined with a cowl separation distance of 8 mm and a cowl wall angle of 30 degrees Referring to Figure 9, a boiler 400 of a central heating system has a pressure relief pipe 402 or blow-off vent from which fluid under pressure can be vented. The vent pipe 100 is fluidly coupled at an end of the pressure relief pipe 402 such that it extends horizontally through the wall 302 of the building in which the boiler 400 is located. The vent pipe 100 can be fluidly coupled using any suitable means such as a soldered joint. The vent pipe 100 is provided with a longitudinal length such that it can extend through a typical wall thickness. Before coupling to the pressure release pipe it can be cut to length as required.

A method 1000 of installing the vent pipe 100 is illustrated in Figure 10. The method comprises inserting 1002 the vent pipe through a hole 202 in the exterior wall 204 of a building. As illustrated in Figure 4, the vent pipe is inserted from the interior side of the wall by inserting the first end 104 of the vent pipe 100 through the wall (i.e. moving the vent pipe in the insertion direction defined above). The vent pipe is pushed through the hole 202 until the cowl 110 and seal 118 protrude from the outer surface 204a of the wall (as illustrated in Figure 5). The method then comprises retracting 1004 the vent pipe 100 until the seal forms a sealing contact with the outer surface of the wall (i.e. by moving it in the retraction direction as illustrated in Figure 6).

The method may further comprise a step of cutting or drilling the hole 202 before the vent pipe is inserted. This may be done as part of the installation method 1000. The hole may alternatively be pre-cut in a separate stage of construction of the building in which the central heating system is to be located, with the vent pipe being installed at a later stage. As discussed above, the hole is cut so that clearance is provided for insertion of the cowl 110 (and retaining members) along with the deformable sealing member 120 in its deformed state. The hole is however sized so that it has a smaller size compared to the size of the deformable sealing member when returned to its relaxed state.

The size, shape and relative position of the cowl 110 described above in relation to the first aspect can also apply to vent pipes that do not include a seal with a resiliently deforniable sealing member. The resiliently deformable sealing member 120 may therefore be absent in some embodiments. A non-deformable seal may instead be provided in the form of a rigid flange extending from the surface of the pipe section 102. In yet other embodiments, the seal 118 may be absent entirely. In both of these cases, the vent pipe may be installed from the outside of the building. If the seal is absent, the spray area and cowl separation distance are defined relative to the outer surface of the wall around the vent pipe when it is installed.

Various modifications will be apparent to the skilled person without departing the scope of the claims. in the described embodiments, the vent pipe is radially symmetric and generally has a circular cross section. The pipe section 102, cowl 110, sealing member 120, first retaining member 122 and second retaining member 124 are therefore generally circular in cross scction. Other shapes may however be possible.

Any reference to the diameter of a component is therefore to be understood to correspond to the greatest cross section& sized measured across that component if it is not circular.

The embodiments described above should be understood as exemplary only. Any feature of any of the aspects or embodiments of the disclosure may be employed separately or in combination with any other feature of the same or different aspect or embodiment of the disclosure and the disclosure includes any feature or combination of features disclosed herein

Claims

CLAIMSA vent pipe for a heating system, comprising: a pipe section having a first end and a second end, the pipe section having at least one aperture at or near the first end; a cowl extending around the first end of the pipe section, the cowl being open in a direction away from the first end of the pipe section so that, in use, fluid flowing along the pipe section and exiting through the at least one aperture will impinge upon the cowl and thereby be deflected at least partially in a direction back along the pipe section away from the first end of the pipe section; and a seal comprising a resiliently deformable sealing member extending around the pipe section so that, in use, the sealing member forms a seal, the seal being located at a position along the pipe section between the second end and the at least one aperture.
2 The vent pipe according to claim I, wherein the sealing member is annular and extends all of the way around an outer surface of the pipe section.
The vent pipe according to any preceding claim, wherein the scaling member formed at least partly from a resiliently deformable material.
4. The vent pipe according to claim 3, wherein the resiliently deformable material is rubber.
The vent pipe according to any preceding claim, wherein the seal further comprises a first retaining member arranged to limit deformation and/or movement of the sealing member in response to a force acting in a direction along the length of the pipe section towards its first end.
6. The vent pipe according to claim 5, wherein the first retaining member extends from, and at least partly around, an outer surface of the pipe section, thereby forming a first retaining surface arranged to limit deformation and/or movement of the sealing member.
7. The vent pipe according to claim 6, wherein the cowl extends radially from the longitudinal axis of the pipe section a distance less than or equal to the first retaining member.
8. The vent pipe according to any preceding claim, wherein the seal further comprises a second retaining member arranged to limit deformation and/or movement of the sealing member in response to a force in a direction along the length of the pipe section towards its second end.
9. The vent pipe according to claim 8, wherein the second retaining member extends from, and at least partly around, the outer surface of the pipe section, thereby forming a second retaining surface arranged to limit deformation and/or movement of the sealing member.
10. The vent pipe according to claim 9, wherein the first retaining member extends radially from the longitudinal axis of the pipe section a greater distance than the second retaining member.
11. The vent pipe according to any preceding claim, wherein the pipe section is formed from an integral length of pipe extending between the first end and the second end.
12. The vent pipe according to any preceding claim, wherein: the fluid directed by the cowl is incident on a spray area, the spray area being defined in a plane normal to the longitudinal axis of the pipe section at a position level with a sealing surface of the sealing member; and the spray area has a cross sectional size less than or equal to 52 mm.
13. The vent pipe according to claim 12, wherein the spray area has a cross sectional size in the range between 40 mm and 50 mm, and preferably equal to 50 mm.
14. The vent pipe according to claim 12 or claim 13, wherein the cowl has an inner concave surface arranged to direct the fluid, the concave surface being bounded by an outer edge; a cowl size is defined as the greatest distance B across the concave inner surface between two points on the outer edge; and the cowl size is in a range between 24 mm and 26 mm, and preferably is equal to 24 mm.
15. The vent pipe according to any of claims 12 to 14, wherein: a cowl separation distance is defined as the axial distance between the outer edge of the concave inner surface and the plane normal to the longitudinal axis of the pipe section at a position level with the sealing surface of the sealing member; and the cowl separation distance is and s preferably equal to 8 mm.n the range between 6 mm and 8 mm,
16. The vent pipe according to any of claims 12 to 15, wherein: a cowl wall angle is defined as the angle extending between a plane tangential to the concave inner surface at a point on its outer edge and a plane normal to the longitudinal axis of the pipe section; and the cowl wall angle is in the range between 28 degrees and 30 degrees, and preferably is equal to 30 degrees.
17. A method of installing a vent pipe for a heating system, the vent pipe being as defined as in any preceding claim, the method comprising: inserting the first end of the vent pipe through a hole in a wall from a first side of the wall such that the cowl and seal protrude from a second side of the wall, retracting the vent pipe until the seal forms a scaling contact with the surface of the second side of the wall.