GB2388889A

GB2388889A - A hydraulic diverter valve

Info

Publication number: GB2388889A
Application number: GB0211939A
Authority: GB
Inventors: Owen Richards
Original assignee: 4C Group Ltd
Current assignee: 4C Group Ltd
Priority date: 2002-05-23
Filing date: 2002-05-23
Publication date: 2003-11-26
Also published as: GB0211939D0

Abstract

A hydraulic diverter valve (101, fig.4) for connection to a combination boiler, the valve body (102, fig.5) comprising an inlet port (114, fig.5), a plurality of outlet ports (160, 162, 164, fig.5) and a central cavity (163, fig.4) containing a valve mechanism for selectively communicating the inlet port with either the bottom outlet (118, fig.4) or the central cavity 163. The side outlets having a common internal thread size (165, fig.4) so that a corresponding plurality of threaded members (connectors 174, fig.9 or blanks 172, fig.7) can selectively be received into any port. The side outlet ports may further be arranged at 90 degrees to each other relative to the valves central axis. The diverter valve further comprising a diaphragm housing 104 made of two components (126, 128, fig.4) fastened together to define a central cavity containing the diaphragm with a fluid inlet (134, fig.4) and outlet (135, fig.4) on either side of the diaphragm. At least one component of the housing having a peripheral rim which seals against the other housing component, the fastening devices (151, fig.4) allowing the components to be rotated relative to each other.

Description

lIYDRAI1LIC DIVERTER VALVE The present invention relates to a hydraulic

diverter valve.

A hydraulic diverter valve for use in combination boilers, primarily for domestic use, is known. The hydraulic diverter valve is also referred to in the art as a hydraulic three-port valve. Since there are three connections on the diverter valve body, such a valve is also referred to as a three-way valve. The valve functions to control the flow of primary circuit water therethrough to enable a combination boiler, on demand, to provide sanitary hot water and also, when required, hot water for heating a central heating circuit. The hydraulic diverter valve is adapted to detect a demand for hot water and thereby to enable the hot water demand to be met by causing primary circuit water to flow through a hot water outlet of the valve. The valve is also adapted to fimction so as to divert primary heating circuit water away from a heating system and through a water/water heat exchanger to heat domestic hot water when required. Since the valve is actuated by the flow of domestic water it is referred to in the art as a hydraulic diverter valve. The valve also acts, in response to hot water demand, to operate electrical microswitches thereby to control the operation of the boiler, pumps, etc. in the hot water and heating system. Cold water only flows through the valve when domestic hot water is required from the combination boiler in which the valve is fitted. When the heating system is not operating, generally in the summer months, the primary heating circuit water only flows through the valve when there is a demand for domestic hot water. When the heating system is operating, generally in the winter months, the primary heating system water flows through the valve continuously.

The construction of a typical known hydraulic diverter valve is illustrated in Figures 1, 2 and 3, Figure 1 showing the valve in the heating position, Figure 2 showing the valve in the hot water position and Figure 3 showing the upper surface of the upper component of the diaphragm housing.

The known hydraulic diverter valve I comprises two main valve parts together with an associated microswitch assembly.

( 2 The two main valve parts comprise a valve body 2 for the diverter valve I and a diaphragm housing 4 which is fitted to the valve body 2. A lower end 6 of the diaphragm housing 4 is received within an upper opening 8 of the diverter valve body 2, and with the ends 6,8 being sealed by an O-ring seal lO disposed therebetween. Grub screws 12, shown in exploded fond in Figures l and 2, are provided for securing the lower end 6 of the diaphragm housing 4 in the upper end 8 of the valve body 2. The ends 11 of the grub screws 12 are received in an annular slot 13 which surrounds the lower end 6 thereby permitting the diaphragm housing 4 and the valve body 2 to be mutually rotated into any desired orientation prior to being secured in a locked position by tightening of the grub screws 12.

The diverter valve body 2 is composed of a body of metal, such as brass, which has been forged and machined to the required configuration. The use of a single forging ensures that the valve body can reliably withstand the water pressures (typically up to 3 Bar) encountered in such systems over a long service period of many years. The valve body 2 has a side inlet 14, which in use comprises the primary circuit inlet to the valve 1, and a side outlet 16, which in use comprises the primary circuit outlet to the heat exchanger (the water/water heat exchanger) of the domestic hot water system. There is also provided in the valve body 2 a bottom outlet 18, which in use comprises a primary circuit outlet to the central heating system. A longitudinally directed shaft 20 is located within the valve body 2 and a second shaft (20a) also extends through the diaphragm housing 4, and two opposed upper and lower valve discs 22,24 are mounted in spaced relation on the shaft 20 via a collar 21 on the shaft 20. The shaft 20 is disposed along the longitudinal axis of the valve. The valve discs 22,24 are located and configured so as selectively to close off fluid communication between the side inlet 14 and either the side outlet 16 or the bottom outlet 18. This valve disc arrangement is adapted only fully to close off one of the two outlets 16,18 at a time, and, as shown in Figure l, when the valve I is in the heating position, the side outlet 16 is normally closed. A valve compression spring 25 is located on an end of the shaft 20 and is biased between the bottom surface of the lower valve disc 24 and an insert 27 located in the bottom outlet 18. There is an option for the valve discs 22, 24 to have O' ring seatings for greater security against let-by.

The diaphragm housing 4 consists of two generally circular shell-like lower and upper housing components 26,28, which are fastened together around their periphery and define therebetween a central generally disclike cavity 30 containing a diaphragm 32, for example of rubber. The diaphragm 32 is annular and is coaxial with the longitudinal axis and sandwiched between the lower and upper housing components 26,28. The lower housing component 26 is integral with the lower end 6 of the diaphragm housing 4 and the shaft 20a extends through the lower component 26 along the longitudinal axis extending through the valve body 2. The peripheral rim 31 of the lower component 26 is provided with a domestic cold water side inlet 34 which in use feeds water into a lower portion of the cavity 30 beneath the diaphragm 32. The peripheral rim 33 of the upper housing component 28 is provided with a side outlet 35 for cold water which in use is directly or indirectly connected to the inlet of the water/water heat exchanger that heats the domestic hot water. An adjustable flow restrictor 36 may be fitted to the side outlet 35 in order to regulate the flow ot water through the valve, and thereafter the boiler, to the domestic hot water tap. The diaphragm 32 has its outer periphery 37 sealingly fitted between opposed mating upper and lower faces 3S,40 ot the lower and upper housing components 26,28 of the diaphragm housing 4. The inner periphery 42 of the diaphragm 32 defines an orifice 44 which is selectively closed or opened by being urged against a restrictor member 46 as a result of biasing action by a helical compression spring 48 or urged away from the sealing member 46 against that bias as a result of water pressure. An annular washer 47 rests against the upper surface of the diaphragm 32 and is connected to the longitudinally directed shaft 20a.

So as to ensure both that the diaphragm housing can reliably withstand the water pressures (typically up to 10 Bar) encountered in such systems over a long service period of many years and that the diaphragm valve is securely held therebetween, the two housing components 26,28 are securely fastened together by a plurality of screws.

As shown in detail in Figure 3, the upper housing component 28 of the diaphragm housing 4 includes the peripheral rim 33 thereof which is annular and has an array of holes 49 therethrough equally spaced around its periphery. In the examples shown, eight holes at an angle of 45 to each other are provided around the peripheral rim 33. Correspondingly, eight threaded holes (not shown) are tapped in the rim of the lower housing component 26

( so that screws 5 l, one of which is shown in each of Figures l and 2, pass through the holes 49 and are tightly screwed into the threaded holes in the lower housing component 26 so that the diaphragm housing 4 is securely assembled together.

The microswitch assembly 50 is mounted on top of the diaphragm housing 4. The shaft 20 attached to the diaphragm 32 via the washer 47 protrudes from the top of the diaphragm housing 4 and operates microswitches (not shown) present in the microswitch assembly 50 when the diaphragm 32 is moved by a domestic water flow (i.e. when there is a hot water demand). The microswitch assembly 50 may contain typically one, two or three microswitches as required, which can be used to switch a number of components in the boiler, for example a gas valve, gas burner, pump, control system, etc. The operation of the known hydraulic diverter valve I will now be described.

When there is no demand for domestic hot water, the diverter valve I is normally in the heating position illustrated in Figure l, i.e. with the bottom outlet 18 being opened. The primary circuit of hot water flows from the primary heat exchanger into the diverter valve I via the side inlet 14 and out through the bottom outlet l 8 to the heating circuit, in order to heat the domestic heating radiators. When, in the heating position, there is additionally a demand for hot water, for example by a hot tap, which is connected to the boiler via the valve 1, being opened, cold water flows through the inlet 34 of the diaphragm housing 4 into the cavity 30 thereby moving the diaphragm 32 upwardly, and the shaft 20a attached to it, and shaft 20 against the bias of the compression spring 48 inside the cavity 30. As shown in Figure 2, water accordingly passes through the orifice 44 in the centre of the diaphragm 32 and out of the housing 4 via the outlet 35 thereby to pass to the domestic hot water circuit of the water/water heat exchanger in order to be heated. The minimum flow rate at which the diaphragm 32 is moved and the valve I is actuated is set as required at the factory, thereby defining a switch point of the valve. This movement of the diaphragm 32, and the shaft 20 attached to it, causes the valve 1 to move to the position shown in Figure 2. In this position, the two valve discs 22,24 on the shaft 20 inside the valve body 2 have been caused to move upwardly, under the influence of the valve compression spring 25, thereby opening the side outlet 16 of the valve body and closing the bottom outlet 18 of the valve body. Thus the primary flow is diverted from the heating system to

the primary circuit of the water/water heat exchanger for heating the domestic hot water In addition, the microswitches in the microswitch assembly 50 are operated, so as to switch on or off the necessary controls, circulating pump, etc. in order for the boiler to produce domestic hot water.

When the demar,d for domestic hot water ceases, by closing the hot tap, the reverse sequence occurs. Thus the water flow through the diaphragm housing is terminated, the diaphragm, shafts and valves return to the normal position, the microswitches are deactivated and the primary circuit water flow is diverted back to the heating system.

While the known hydraulic diverter valve operates satisfactorily, it does suffer from technical problems. The known diverter valve includes a "three-way" valve body because it is required to have one inlet and two outlets. The relative positioning and orientation of these three inlets/outlets can vary from application to application and so the known hydraulic three-way diverter valve has been supplied with one of three primary valve body types, known as "D", "E" or "F". For primary body type D the side inlet 14 and the side outlet l are opposite to each other, similar to what is shown in Figures l and 2. Fo primary body type E, looking down on the valve body from above, the side outlet 16 is at 90 to the side inlet 14, and on the right-hand (i.e. clockwise) side thereof. For primary valve body type F. looking down on the valve body from above, the side outlet 16 is on the leh-hand side, i.e. anticlockwise, relative to the side inlet 14.

In addition, for the diaphragm housing of the known hydraulic three-way diverter valve, various relative orientations of the inlet 34 relative to the outlet 35 are required, to accommodate different applications of the valve. In Figures I and 2 the inlet 34 and outlet 3 5 are opposite each other but in the known hydraulic three-way diverter valve the relative position and orientation of the inlet 34 and outlet 35 may be varied by disassembling the diaphragm housing 4. This requires removing the screws 51, reorienting the upper component 28 relative to the lower component 26 by relative rotation therebetween, and then reassembling the diaphragm housing 4. In the illustrated valve, the inlet 34 and outlet 35 can be disposed in seven different orientations, each orientation being at 45 to the adjacent orientations. Not only is this disassembly of the diaphragm housing time consuming, there is also a danger that the parts of the diaphragm valve could be

inadvertently knocked out of position or otherwise damaged, or dirt could be entrained in the valve.

The upper component 28 of the diaphragm housing 4 is provided with the outlet 35 connection, which in Figure 1 is shown as a threaded male connector. Since the hydraulic diverter valve is intended to be incorporated into a variety of different domestic combination boilers, it is necessary to provide a variety of different upper components for the diaphragm housing 4, each incorporating a different connection type for the outlet 35 connection. In the known hydraulic three-way diverter valve, four different upper components for the diaphragm housing are required to be manufactured and supplied, each incorporating a respective outlet connection type.

In the known hydraulic three-way diverter valve, the requirement for a variety of different valve bodies, disassembly of the diaphragm housing to ensure that it is reassembled in the correct orientation, and a variety of different upper components for the diaphragm housing requires a larger number of permutations of the hydraulic three-way valve to be stocked and supplied. In particular when the hydraulic three-way diverter valves are required to be supplied as spare parts, this leads to the disadvantage that the plumber intending to fit a replacement valve as a spare part, both for current and obsolete models of combination boilers, is required to stock an extremely large number of replacement hydraulic diverter valves' otherwise there is a possibility that he may turn up at the domestic premises in order to change the valve but not be in possession of the correct valve. Alternatively he must visit the boiler first and then go and purchase the correct valve required, resulting in a delay in fixing the appliance.

There is therefore a need in the art for a hydraulic diverter valve for use with domestic combination boilers, which has a universal construction at least in some or all of its parts, thereby overcoming the stock keeping problems of known valves and/or permitting the structure and orientation of the valve to be modified on site by a service engineer so as to be customised for the required appliance.

The present invention partially aims to meet this need.

Accordingly, the present invention provides a valve body for a hydraulic diverter valve for connection to a boiler, the valve body comprising a body member, an inlet port, a bottom outlet port, a central cavity, a valve mechanism for selectively communicating the inlet port with one of the bottom outlet port and the central cavity, and a plurality of side outlet ports communicating with the central cavity, each side outlet port having an internal threaded surface for threadably receiving a threaded member, each threaded surface having a common configuration so that a corresponding plurality of threaded members can selectively be received into any of the side outlet ports.

Preferably, the valve body comprises three side outlet ports.

Preferably, each side outlet port is disposed with the axis at 9() to each other on the body member. The present invention also provides a kit of parts for forming a hydraulic diverter valve for connection in a boiler, the kit including the valve body of any foregoing claim in combination with at least one tubular threaded outlet connector for threaded connection each with any respective one of the plurality of side outlet ports for establishing fluid connection of the central cavity through the tube of the threaded outlet connector and at least one threaded blanking member for threaded connection with each of the remaining side outlet ports for closing the respective port.

Preferably, the kit of parts comprises one threaded outlet connector and two blanking members. The present invention further provides a hydraulic diverter valve for connection in a boiler, the hydraulic diverter valve including a valve body comprising a body member, an inlet port, a bottom outlet port, a central cavity, a valve mechanism for selectively communicating the inlet port with one of the bottom outlet port and the central cavity, and a plurality of side outlet ports communicating with the central cavity, each side outlet port having an internal threaded surface for threadably receiving a threaded member, each threaded surface having a common configuration, and the threaded members comprising a

tubular threaded outlet connector threaded into one of the plurality of side outlet ports thereby establishing fluid correction of the central cavity through the tube of the threade outlet connector and at least one threaded blanking member each threaded into a respective one of the remaining side outlet ports thereby closing the respective port.

Preferably, the hydraulic diverter valve comprises three side outlet ports.

Preferably, each side outlet port is disposed with the axis at 90 to each other on the body member. Preferably, the hydraulic diverter valve further comprises a diaphragm housing connected to the valve body, the diaphragm housing comprising first and second housing components, which are fastened together to define thercbetween a central cavity containing a diaphragm valve, a fluid inlet provided on the first housing component and communicating with an inlet side of the diaphragm valve and a fluid outlet provided on the second housing component and communicating with an outlet side of the diaphragm valve, one of the first and second housing components having a peripheral rim which is sealingly fitted to the other housing component thereby to seal the central cavity, and at least one fastening device for securing the peripheral rim against the other housing component, the at least one fastening device being adapted to permit the first and second housing components to be rotated relative to each other, thereby permitting relative rotation of the inlet and the outlet, while the first and second components are fastened together.

Preferably, a plurality of the fastening devices are located in spaced relation peripherally around the peripheral rim of the first housing component.

Preierably, the at least one fastening device is adapted to be movable between a first position at which the fastening device bears against a surface of the peripheral rim and a second position which the fastening device is remote from the surface of the peripheral nm. Preferably' each fastening device comprises a threaded member which has a threaded shaft, which is received in a threaded hole in the said other housing component and is

( 9 adjacent to the peripheral surface of the peripheral rim, and a head portion which is arranged to bear against an upper surface of the peripheral rim in the first position.

Preferably, eight threaded members are located peripherally around the peripheral rim.

Preferably, the peripheral rim is circular.

Preferably, the fluid outlet of the diaphragm housing incorporates a universal valve connection comprising a threaded connector piece.

Preferably, the threaded connector piece is externally threaded so as to comprise a male threaded part.

Preferably, the threaded connector piece is comprised in an adaptor piece which is removably attached to the second housing component, the adaptor piece being configured so as to be selectively attachable in one of a plurality of orientations so as to vary the position of the axis of the male threaded part.

Preferably, the adaptor piece has an inwardly directed tubular part which has an elliptical cross section is removably received in a correspondingly shaped hole in the second housing component, and the male threaded part is offset relative to the centre axis of the inwardly directed tubular part so that the adaptor piece is selectively attachable in one of two orientations so as to vary the position of the axis of the male threaded part.

Preferably, wherein the adaptor piece has a flange? which includes fixing holes which are offset relative to the centre axis of the inwardly directed tubular part, and by means of which the adaptor piece is affixed to a mounting surface of the second housing component.

The present invention yet further provides a kit of parts for forming a hydraulic diverter valve for connection in a boiler, the kit including the hydraulic diverter valve according to the invention in combination with a plurality of valve connectors, each including a threaded part for threadable connection with the connector piece and each having a respective configuration for engagement with a respective sanitary fitting.

Preferably, a first valve connector has a male outer threaded surface for engagement by a sanitary fitting, a second valve connector has an outer surface provided with an O-ring seal for push fitting into an end of a hose, and a third valve connector has a female union nut fitted thereon.

An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic sectional view through a known hydraulic diverter valve in a heating position; Figure 2 is a schematic sectional view through the known hydraulic diverter valve of Figure 1 in a hot water position; Figure 3 is a schematic perspective view of an upper housing component of a diaphragm housing of the known hydraulic diverter valve of Figure 1; Figure 4 is a schematic side view through an embodiment of a hydraulic diverter valve in accordance with the invention; Figure 5 is a schematic part-sectional/part-side view of a valve body for the hydraulic diverter valve of Figure 4 when viewed from the opposite direction from that of Figure 4; Figure 6 is a schematic sectional view through the valve body of Figure 5 when viewed from the left hand side of Figure 4; Figure 7 is a schematic side view of a blanking plug for incorporation into the hydraulic diverter valve of Figure 4; Figure 8 is a schematic front view of the blanking plug of Figure 7;

( 11 Figure 9 is a schematic part-sectional side view of a connector for incorporation in the valve body of the hydraulic diverter valve of Figure 4; Figure 10 is a schematic front view of the connector of Figure 9; Figure 11 is a schematic perspective and partially exploded view of the hydraulic diverter valve of Figure 4 in conjunction with different sanitary connections and an adaptor for fitting to the diaphragm housing; Figure 12 is a schematic sectional view of a first embodiment of a cold water outlet valve connector for incorporation on the diaphragm housing of the hydraulic diverter valve of Figure 4; Figure 13 is a schematic sectional view of a second embodiment of a cold water outlet valve connector for incorporation on the diaphragm housing of the hydraulic diverter valve of Figure 4; and Figure 14 is a schematic sectional view of a third embodiment of a cold water outlet valve connector for incorporation on the diaphragm housing of the hydraulic diverter valve of Figure 4.

In accordance with the present invention, the known hydraulic diverter valve described herein with reference to Figures 1 to 3 has been modified in a number of different respects.

For brevity, the construction and operation of the hydraulic diverter valve of the present invention will not be repeated insofar as it is the same as that of the known hydraulic diverter valve described herein.

The hydraulic diverter valve of the illustrated embodiment, designated generally as 101, of the present invention which is shown in Figure 4 comprises two main valve parts together with an associated microswitch assembly. The two main valve parts comprise a valve body 102 for the diverter valve 101 and a diaphragm housing 104 which is fitted to the valve body 102 (Fig 4). A microswitch 150 is mounted on top of the diaphragm housing 104.

( 12 In one aspect of the present invention, the valve body 102 has been modified so as to comprise a universal valve body which may readily be adapted to cover all valve permutations corresponding to primary valve body types D, E and F described above with respect to the known hydraulic valve diverter.

In the valve body] 02, the side inlet 114 and bottom outlet 118 are provided, as for the known hydraulic diverter valve. The valve body 102 is provided with three primary outlet connection ports 160,162,164 which, as may be seen additionally from Figures 5 and 6, are respectively on one of three sides 166,168,170 of the valve body 102, with the ports 160,162, 164 communicating with and disposed around a central manifold cavity 163 located above the valve discs, collar and shah (not shown) as for the known valve. Two of the ports 16(), l 64 are located on opposite sides 166,170 of the valve body 102. The third port 162 is located in the side 168 of the valve body 102 extending between the two opposed sides 166,170. Each port 160,162,164 is provided with an internal cylindrical threaded surface 165.

The valve body 102 may rapidly be converted into a valve body of the D, E or F type by the insertion into the required parts of the valve body, in the desired configuration, of two threaded blanking plugs, one of which is shown in Figures 7 and 8, and a threaded outlet connector which is shown in Figures 9 and 10. The two blanking plugs 172 and the outlet connector 174 together comprise a kit of parts which would be supplied together with the valve body 102 to enable any one of the three desired valve body outlet configurations D, E or F to be readily provided by a purchaser or user of the valve.

Each blanking plug 172 comprises a rear cylindrical portion 176 having an outer cylindrical threaded surface 178 adapted to mate with the internal cylindrical threaded surface 165 of each of the ports 160,162,164. The blanking plug 172 is also provided with a front part 180 comprising a plate member diametrically larger than the rear portion 176.

The plate member 180 includes a recessed slot 182 extending thereacross for receiving a screw driver bit to enable the blanking plug 172 to be screwed into the required port 160,162,164.

( 13 The outlet connector 174 defines a central cylindrical bore 184 therethrough and includes a rear portion 186 having an outer cylindrical threaded surface 188 adapted to mate with the internal threaded surface 165 of each of the ports 160,162,164. The outlet connector 174 also includes a front portion 190 having an outer cylindrical threaded surface 192, the thread and diameter of which are adapted to mate with connections conventionally used in the art to enable the outlet connector 174 to be connected to the domestic hot water heat exchanger in the boiler. A central portion 194 of the outlet connector 174 is disposed between the rear portion 184 and the front portion 190 and defines laterally opposed flattened surfaces 196,198 to enable the outlet connector 174 securely to be screwed into a respective port 160,162,164 by use of a wrench or spanner engaging the opposed surfaces 196,198.

Each of the blanking plugs 179 and the outlet connector 174 is typically made of brass. It will be apparent to those skilled in the art that the blanking plugs 172 and the outlet connector 174 may be modified to enable other tools to be used (for example a hexagonal socket or Allen key) having a hexagonal outer surface to screw the blanking plugs and or the outlet connector into the valve body 102.

In accordance with this aspect of the invention, only one valve body 102 is required to achieve all the three valve permutations D, E and F and accordingly the valve body is a universal one for this application. The valve body 102 is supplied with a kit consisting of the two threaded blanking plugs 172 and the threaded outlet connector 174. By providing auniversal valve body, together with the kit of the blanking plugs and the outlet connector, this can significantly reduce the number of permutations of the valve, thereby reducing the number of spares required to be manufactured and stocked.

In accordance with another aspect of the invention, the hydraulic head of the hydraulic diverter valve, constituted by the diaphragm housing 104, has been modified so as to permit ready adjustment of the relative rotational positions of the cold water side inlet 134 and the side outlet 135 of the diaphragm housing 104 without requiring disassembly of the diaphragm housing 104, and additionally permitting greater flexibility of the relative angular orientation of the side outlet 135 with respect to the side inlet 134.

( As may be seen from Figure 4, the upper housing component 128 of the diaphragm body 1()4 is fastened to the lower housing component 126 by a plurality of fixing screws 151 peripherally arranged around the upper housing component 128 with the fixing screws 151 being received in threaded holes (not shown) in the upper surface 138 of the lower housing component 126. However, in accordance with this embodiment of the invention, the screws 151, each of which consists of a head portion 152 and a threaded shaft 153, are adjacent an outer peripheral surface 154 of the peripheral edge 233 of the upper housing component 128. Thus the threaded shaft 153 of each screw 151 lies adjacent the peripheral surface 154 and the lower surface 155 ofthe screw head 152 of each screw 151 hears forcefully against the upper surface 156 of the peripheral rim 233. In this way, when all the screws 151 are securely tightened, the upper housing component 128 is securely fastened to the lower housing component 126 of the diaphragm housing 104. In the illustrated embodiment, eight fixing screws 51 are employed (although this number may be varied) and this ensures a secure fastening of the diaphragm housing 104 so that the diaphragm housing does not leak under the elevated water pressure during service.

However, the outlet 135 position provided on the upper housing component 128 can easily and quickly be adjusted relative to the inlet 134 position by only slackening the fixing screws] 51 and rotating the upper housing component 128 of the diaphragm housing 104 relative to the lower housing component 126 (the latter of which may also be called the mid-body of the hydraulic diverter valve). The peripheral rim 233 of the upper housing component 128 of the diaphragm housing 104 remains captive under the heads 152 of the fixing screws 151 and so cannot be removed, thereby overcoming the problem of the prior art where parts of the diaphragm assembly could be exposed and the cavity of the diaphragm housing could be subject to entrainment of dirt. Thus the outlet 135 can be rotated relative to the inlet 134 to any desired position, not limited by the position of the fixing screws as in the prior art to one of a small number of indexed positions, because the

capture of the peripheral rim 233 by the fixing screws 151 permits small adjustments in the angular position of the peripheral rim since the fixing screws I 5 I can bear against any part of the upper surface 156 of the peripheral rim 233. When it is desired to move the outlet 135 relative to the inlet 134 by an angle which is greater than the angle between adjacent fixing screws, then only one or two fixing screw(s) 151 need to be removed completely thereby permitting the relative rotation of the upper and lower housing components 128,126 about a greater angle, "hereafter the fixing screw(s) 151 can be

( 15 replaced. Thus the upper and lower housing components 128?126 can be freely moved around practically any angle, although in a stepwise fashion for any large angles, and provided that the inlet 134 and the outlet 135 do not abut to such an extent that it is not possible to attach the required connections thereto, without ever having to disassemble the diaphragm housing 104.

As in the known hydraulic diverter valve, the relative angular position of the diaphragm housing 104 comprising the hydraulic head can be adjusted with respect to the valve body 102 by slackening the two grub screws 12, as shown in Figures 1 and 2, then rotating the diaphragm housing 104 to the required position, and thereafter re-tightening the grub screws 12.

Since the diaphragm housing does not need to be disassembled to change the angular orientation ofthe inlet 134 and the outlet 135, the diaphragm is not disturbed and there is no danger of a plumber or fitter mislocating the seal, misaligning the diaphragm or even, as can be done, replacing the diaphragm upside down in the diaphragm housing 104.

In accordance with a further aspect of the hydraulic diverter valve of the embodiment of the invention, the outlet 135 of the diaphragm housing 104 provided on the upper housing component 128 has been modified to provide a universal valve connection, thereby permitting the hydraulic diverter valve of the present invention to be readily customised or adapted by a service engineer to suit and fit to whatever boiler the valve is required to be fitted into. This obviates the requirement for a number of different upper housing components 128, each with a respective valve fitting, being required either individually or as part of a diaphragm housing.

As shown in Figures 4 and 11, the outlet 135, which is to be connected to the sanitary inlet of the waterlwater heat exchanger that heats the domestic hot water, is constituted by an adaptor piece 200 which is removably attached to the upper housing component 128 of the diaphragm housing 104, adjacent to the flow restrictor 136 if present. The adaptor piece 200 has an inwardly directed male tubular part 300 having an elliptical cross section which is received in a corresponding elliptically shaped hole 302 in a manifold 304 of the upper housing component 128. The adaptor piece 200 has a square flange 306, with a pair of

holes 308 therethrough, which are located in an offset position relative to the axial centre of the male part 300 and the flange 306. The square flange 306 is shaped to fit in a corresponding square recess 307 of the manifold 304, at the centre of which recess 307 the elliptically shaped hole 302 is located. The flange 306 and correspondingly shaped recess 307 may be other shapes than square. The adaptor piece 200 also has an externally threaded outwardly directed part 310 which is also located in an offset position relative to the axial centre of the male part BOO, so that the flange 306 and the externally threaded part 310 are on opposite ends of the adaptor piece 200. The manifold 304 has a mounting surface 312 surrounding the elliptically shaped hole 302 which is provided with two pairs of opposed threaded holes 314, 316, each pair being either above or below the centre axis of the hole 302 and each pair having the two holes on opposed sides of the hole 302. The adaptor piece 200 is fitted to the manifold 304 by screws or bolts (not shown) passing through the holes 308 in the flange 306 and into one pair of the holes 314, 316. depending upon the desired orientation of the externally threaded part 310 which may thereby be selectively disposed in a high or a low configuration. The flange 306 is thereby fitted in the recess 307. fine adaptor piece 200 can be removed if desired and rotated by an angle of 18() degrees when it is necessary to change the configuration of the externally threaded part 310, which is dependent upon the particular combination boiler to which the valve is to be fitted The externally threaded part 310 is configured so as to be receivable as a male threaded part into a correspondingly threaded female part of any one of a kit of valve connectors such as those shown in Figures 12, 13 and 14.

Referring to Figure 12, a first valve connector 204 has a male outer threaded surface 206 for engagement by a sanitary fitting, for example in a boiler, and an inner female threaded surface 208 for engagement with the connection piece 200. The valve connector 204 is additionally provided with an internal hexagonal surface 210 for a part of the central bore 2]2 extending therethrough to enable tightening of the valve connector 204 onto the connection piece 200 using a tool such an Allen key with an outer hexagonal surface. This connector 204 may have differing thread lengths, for example corresponding to V35 and V36 sanitary connections known in the art.

Figure 13 shows a second embodiment of a valve connector 214 which correspondingly also includes an internal female threaded surface 216 for fitting onto the male threaded l

surface of the connector piece 200 and the outer surface 218 of the valve connector 214 is provided with an O-ring seal 220 partially recessed in an annular slot 922 provided in the outer surface 218. This constitutes a "push-fit'' connector as used in some boilers. As for the valve connector of Figure 12, the valve connector of Figure 13 includes a bore 224, a part of which defines a hexagonal internal surface 226 to enable the valve cormector 214 to be fitted onto the connection piece 200 by a hexagonal tool.

Referring to Figure 14, a third embodiment of a valve connector 228 is shown which, like the valve connectors of Figures 12 and 13, has a central bore 230 surrounded partly by an internal threaded female surface 232 and by an internal hexagonal shaped surface 234.

The outer cylindrical surface 236 of the valve connector 228 includes at an end remote from the female threaded surface 232 a radially outwardly directed rim 23X. An annular threaded mounting piece 240 comprising a female union nut is loosely fitted over the outer surface 236 and is held captive on the outer surface 236 by the rim 238 when the valve connector 228 is fitted onto the connection piece 200. The annular mounting piece 240 includes an internal female threaded surface 242 for threaded engagement with a correspondingly shaped male threaded surface of a sanitary fitting and an outer hexagonal surface 244 for engagement with a wrench or spanner.

The valve connector configurations of Figures 12 (having the two different thread lengths), 13 and 14 correspond to connectors V35 and V36, V37 and V38 respectively which are known in the art for hydraulic diverter valves. Other valve connections may be employed in accordance with the present invention.

By the provision of a kit of different valve connectors, together with the adaptor piece, thereby to constitute a universal water outleVsanitary inlet connection on the upper housing connector of the valve, this again reduces stocktaking problems in requiring fewer different diaphragm housing upper components to be stocked and supplied, and reduces the number of permutations of the different valves which are required to be stocked and kept by a service engineer. The service engineer can readily adapt the basic universal valve structure to the required boiler.

( 18 Other modifications within the scope of the present invention will be apparent to those skilled in the art.

Claims

( 19 CLAIMS:

1. A valve body for a hydraulic diverter valve for connection to a boiler, the valve body comprising a body member, an inlet port, a bottom outlet port, a central cavity, a valve mechanism for selectively communicating the inlet port with one of the bottom outlet port and the central cavity, and a plurality of side outlet ports communicating with the central cavity, each side outlet port having an internal threaded surface for threadably receiving a threaded member, each threaded surface having a common configuration so that a corresponding plurality of threaded members can selectively be received into any of the side outlet ports.

2. A valve body according to claim I comprising three side outlet ports.

3. A valve body according to claim I or claim 2 wherein each side outlet port is disposed with the axis at 90 to each other on the body member.

4. A kit of parts for forming a hydraulic diverter valve for connection in a boiler, the kit including the valve body of any foregoing claim in combination with at least one tubular threaded outlet connector for threaded connection each with any respective one of the plurality of side outlet ports for establishing fluid connection of the central cavity through the tube of the threaded outlet connector and at least one threaded blanking member for threaded connection with each of the remaining side outlet ports for closing the respective port.

5. A kit of parts according to claim 4 comprising one threaded outlet connector and two blanking members.

6. A hydraulic diverter valve for connection in a boiler, the hydraulic diverter valve including a valve body comprising a body member, an inlet port, a bottom outlet port, a central cavity, a valve mechanism for selectively communicating the inlet port with one of the bottom outlet port and the central cavity, and a plurality of side outlet ports communicating with the central cavity, each side outlet port having an internal threaded surface for threadably receiving a threaded member, each threaded surface having a

( 20 common configuration, and the threaded members comprising a tubular threaded outlet connector threaded into one of the plurality of side outlet ports thereby establishing fluid correction of the central cavity through the tube of the threaded outlet connector and at least one threaded blanking member each threaded into a respective one of the remaining side outlet ports thereby closing the respective port.

7. A hydraulic diverter valve according to claim 6 comprising three side outlet ports.

8. A hydraulic diverter valve according to claim 6 or claim 7 wherein each side outlet port is disposed with the axis at pO to each other on the body member.

9. A hydraulic diverter valve according to any one of claims 6 to 8, further comprising a diaphragm housing connected to the valve body, the diaphragm housing comprising first and second housing components, which are fastened together to define therebetween a central cavity containing a diaphragm valve, a fluid inlet provided on the first housing component and communicating with an inlet side of the diaphragm valve and a fluid outlet provided on the second housing component and corrununicating with an outlet side of the diaphragm valve, one of the first and second housing components having a peripheral rim which is sealingly fitted to the other housing component thereby to seal the central cavity, and at least one fastening device for securing the peripheral rim against the other housing component, the at least one fastening device being adapted to permit the first and second housing components to be rotated relative to each other, thereby permitting relative rotation of the inlet and the outlet, while the first and second components are fastened together.

10. A hydraulic diverter valve according to claim 9 wherein a plurality of the fastening devices are located in spaced relation peripherally around the peripheral rim of the first housing component.

11. A hydraulic diverter valve according to claim 9 or claim 10 wherein the at least one fastening device is adapted to be movable between a first position at which the fastening device bears against a surface of the peripheral rim and a second position which the fastening device is remote from the surface of the peripheral rim.

12. A hydraulic diverter valve according to claim 11 wherein each fastening device comprises a threaded member which has a threaded shaft, which is received in a threaded hole in the said other housing component and is adjacent to the peripheral surface of the peripheral rim, and a head portion which is arranged to bear against an upper surface of the peripheral rim in the first position.

13. A hydraulic diverter valve according to claim 11 wherein eight threaded members are located peripherally around the peripheral rim.

14. A hydraulic diverter valve according to any one of claims 9 to 13 wherein the peripheral rim is circular.

15. A hydraulic diverter valve according to any one of claims 9 to 14 wherein the fluid outlet of the diaphragm housing incorporates a universal valve connection comprising a threaded connector piece.

16. A hydraulic diverter valve according to claim 15 wherein the threaded connector piece is externally threaded so as to comprise a male threaded part.

17. A hydraulic diverter valve according to claim 15 or claim l 6 wherein the threaded connector piece is comprised in an adaptor piece which is removably attached to the second housing component, the adaptor piece being configured so as to be selectively attachable in one of a plurality of orientations so as to vary the position of the axis of the male threaded part.

18. A hydraulic diverter valve according to claim 17 wherein the adaptor piece has an inwardly directed tubular part which has an elliptical cross section is removably received in a correspondingly shaped hole in the second housing component, and the male threaded part is offset relative to the centre axis of the inwardly directed tubular part so that the adaptor piece is selectively attachable in one of two orientations so as to vary the position of the axis of the male threaded part.

19. A hydraulic diverter valve according to claim 18 wherein the adaptor piece has a flange, which includes fixing holes which are offset relative to the centre axis of the inwardly directed tubular part, and by means of which the adaptor piece is affixed to a mounting surface of the second housing component.

20. A kit of parts for forming a hydraulic diverter valve for connection ire a boiler, the kit including the hydraulic diverter valve according to any one of claims 15 to 19 in combination with a plurality of valve connectors, each including a threaded part for threadable connection with the connector piece and each having a respective configuration for engagement with a respective sanitary fitting.

21. A kit of parts according to claim 20 wherein a first valve connector has a male outer threaded surface for engagement by a sanitary fitting, a second valve connector has an outer surface provided with an O-ring seal for push fitting into an end of a hose, and a third valve connector has a female union nut fitted thereon.

22. A hydraulic diverter valve substantially as hereinbefore described with reference to Figures 4 to 14 of the accompanying drawings.

23. A kit of parts for forming a hydraulic diverter valve for connection in a boiler valve substantially as hcreinbefore described with reference to Figures 4 to 14 of the . accompanying drawings.