A FILLING DEVICE FOR A PRESSURISED HEATING CIRCUIT

Abstract

A filling loop device for a pressurized heating system comprising means defining a fluid passage having, an inlet port connectable to a fluid supply and an outlet port connectable to a heating system fluid circuit; and a dead man valve interposed in the passage between the inlet port and the outlet port, said dead man valve biased to a normally closed condition to shut off fluid flow through the channel in either direction when unattended, and manually operable to an open condition to permit fluid to flow from the inlet port to the outlet port. Also provided is a method of charging a pressurized boiler and heating circuit.

Claims

1-18. canceled

19. A filling loop device for a pressurized heating system comprising: means defining a fluid passage having, an inlet port connectable to a fluid supply and an outlet port connectable to a heating system fluid circuit; and a dead man valve interposed in the passage between the inlet port and the outlet port, said dead man valve biased to a normally closed condition to shut off fluid flow through the channel in either direction when unattended, and manually operable to an open condition to permit fluid to flow from the inlet port to the outlet port; a casing having; a fluid passage with an inlet port and an outlet port and, a spool chamber; a spool slidably housed in the spool chamber, said spool including a through passage capable of communicating the inlet port and outlet port for fluid flow therebetween, and bias means to urge the spool so that a lower part of the spool obstructs the passage, and a drain passage formed in the lower part of the spool and communicable between the outlet port and a drain port formed in the lower part of the spool chamber.

20. A device according to claim 19 comprising a pressure regulator valve pre-set to prevent excess pressurisation of a heating system.

21. A device according to claim 19 wherein the bias means comprises a spring to spring bias the spool to close a fluid passage through the valve and a manual actuator operable to displace the spool in opposition to the spring force while manually attended.

22. A device according to claim 21 wherein the actuator comprises a press button.

23. A device according to claim 19 wherein the drain port is formed in a base of the spool chamber.

24. A device according to claim 19 wherein the drain port is provided with a hose coupling.

25. A device according to claim 24 wherein the hose coupling is a nipple.

26. A device according to claim 19 wherein the drain passage is isolated from the through passage.

27. A filling loop device for a pressurized heating system comprising: means defining a fluid passage having, an inlet port connectable to a fluid supply and an outlet port connectable to a heating system fluid circuit; and a dead man valve interposed in the passage between the inlet port and the outlet port, said dead man valve biased to a normally closed condition to shut off fluid flow through the channel in either direction when unattended, and manually operable to an open condition to permit fluid to flow from the inlet port to the outlet port; wherein said deadman valve is provided by a pressure regulator valve pre-set to prevent excess pressurisation of a heating system; said pressure regulator valve having means biased to normally close a fluid passage through the regulator valve and an actuator manually operable against the bias to open the fluid passage.

28. A device according to claim 27 wherein the regulator valve comprises a displaceably mounted piston valve seat spring biased to close a fluid passage formed between the piston valve seat and a poppet valve.

29. A device according to claim 27 comprising a cam rotatable from a closed condition to an open condition, where in the open condition the cam acts against the piston valve seat to open the fluid passage between the poppet valve and the piston valve seat.

30. A device according to claim 29 wherein the rotary axis of the cam is offset such that the spring force always displaces the cam towards the closed condition.

31. A device according to claim 27 comprising a shaft sealingly journaled through a casing of the dead-man regulator valve to couple with a manual actuator provided by a knob.

32. A boiler in combination with a filling loop device according to claim 27. 33 (New) A method of charging a pressurized boiler and heating circuit comprising the steps of: providing a fluid channel between a mains water supply and the pressurized heating circuit, said fluid channel including a dead-man shut off valve having a manually operable actuator configured to close the channel when not manually actuated; manually actuating the dead-man valve to allow water to flow from the mains supply to the heating circuit until the heating circuit reaches a specified operating pressure; releasing the dead-man valve actuator to shut off the channel.

34. A method according to claim 33 comprising leaving the fluid channel in place after charging the pressurized boiler and heating circuit.

35. A method according to claim 33 comprising providing a one way check valve in the channel to prevent backflow from the heating circuit to the mains supply.

36. A method according to claim 33 comprising providing a pressure regulation valve in the channel pre-set to regulate the maximum pressure of water deliverable to the heating circuit in order to prevent charging the heating circuit to a damaging excessive pressure.

Description

BRIEF DESCRIPTION

[0029] Embodiments of a filling device for a pressurised heating circuit constructed in accordance with the present invention, will now be described, by way of example only, with reference to the accompanying illustrative drawings, in which:

[0030] FIG. 2A shows a SW isometric view of a first embodiment of the device installed in a part of a pressurised heating circuit including a boiler;

[0031] FIG. 2B is an exploded plan view of the filling device of FIG. 2A;

[0032] FIG. 2C is a sectional detail of a first variant of a dead-man valve used in the first embodiment;

[0033] FIG. 2D is a flow chart showing the new process for using the first embodiment;

[0034] FIG. 3A is a SW isometric view of a second embodiment of the device installed in a part of a pressurised heating circuit including a boiler;

[0035] FIG. 3B is an enlarged detail side elevation of the filling device of the second embodiment;

[0036] FIG. 3C is a further enlarged sectional elevation through the dead-man valve of the second embodiment;

[0037] FIG. 3D is a flowchart of the process of using the second embodiment,

[0038] FIG. 4A shows an isometric view of a third embodiment of the invention wherein a dead-man valve is integrated with a regulator valve;

[0039] FIG. 4B shows a plan vie of the third embodiment in a closed condition;

[0040] FIG. 4C shows a sectional plan view through FIG. 4B;

[0041] FIG. 4D shows a plan view of the third embodiment in the open condition for charging the heating circuit;

[0042] FIG. 4E shows a sectional plan view of FIG. 4D.

DETAILED DESCRIPTION OF FIGURES

[0043] Features common to the prior art of FIG. 1 are referenced with the same numerals. Thus FIG. 2A shows a boiler or furnace 1 plumbed into a heating circuit to circulate hot water through a pressurised heating circuit pipe 2.

[0044] An inlet valve 4 is coupled to a terminus of the mains water pipe 3 by means of an inlet connector 10. In this case the inlet connector 10 is a conventional compression coupling; however other known forms of coupling including press fit, cement or solder may be employed. The coupling 10 couples an isolation valve 12 to the end of the mains water pipe 3.

[0045] A dead man valve is provided by a push button valve 14 configured to open the fluid flow pathway when the push button 15 is pushed and thereby displaces a spool against a bias to open a passage through the valve. When the button is released the bias displaces the spool and button to close the fluid passage. In the embodiment shown the push button valve 14 has an upstream port adapted to be coupled to a downstream port of the isolation valve 12 by means of a BSP threaded coupling.

[0046] A downstream port 14d of the push button valve 14 is coupled to a flexible tubing portion (hose) 16 to provide fluid communication with the outlet valve 6. The outlet valve 6 has a housing 24 and includes an isolation valve 18 which includes a check valve 22, connected such that flow from the inlet 4 to the outlet valve is allowed while reverse flow is prevented. The outlet valve 6 is coupled to a spur off the heating circuit pipe by means of a compression coupling outlet connector 20. In some embodiments the check valve in the outlet valve 6 is a double check valve to add reliability.

[0047] FIG. 2C shows a sectional detail of the push button valve 14 with the button depressed. The push button valve 14 has a casing 14a with a fluid passage 14b communicating a female threaded inlet port 14c and outlet port 14d. The passage 14b is intersected by a spool chamber 14e containing a spool 14f. The spool 14f is in this case cylindrical. Anti-rotating means (not shown) may be provided to prevent the spool from rotating around its axis. Such means may include a tongued washer, located in nut 15a and engaging a groove in the stem 15b of the push button.

[0048] The anti-rotating means ensures that a through passage 14g extending diametrically through the spool 14f is aligned with the passage 14b to facilitate the passage of water through the valve when the pushbutton is depressed. A compression spring 14k is arranged to urge the spool 14f up into a condition where a lower part 14i of the spool obstructs the passage 14b as can be seen in FIG. 3C.

[0049] An “O” ring 14m′ encircles the spool above the upper part, a middle “O” ring 14m″ encircles the spool between the upper and lower part and a lower “O” ring encircles the spool at the bottom of the lower part. The “O” rings provide a fluid sealing bearing surface for the spool in the cylindrical spool chamber. FIG. 2D is a flow chart showing the method of using the device of the first embodiment. The inlet valve 4 and outlet valve 6 will be installed with the heating system and will remain in place on the mains supply 3 and heating circuit spur 2a as in the conventional prior art arrangement.

[0050] In step 2.1 the fill loop device is coupled between the inlet and outlet valves 4 and 6 to provide a channel for the passage of mains water. At step 2.2 the isolation valves 12 and 18 are opened. At step 2.3 the press button of the dead-man valve is depressed thereby opening a passage for the flow of mains water from the mains pipe 3 to the heating circuit spur 2a. This pressurises the heating circuit 2 and the pressure is read at step 2.4 from the pressure gauge 7 by the user until a manufacturer specified pressure is reached. When the specified pressure is reached the press button valve is released at step 2.5. The isolation valves 12 and 18 should then be closed at step 2.6. Conveniently the filling loop may then be left in place at step S2.7 since there is no possibility of water flow through the filling loop device so long as the valves function correctly. Even if step 2.6 is overlooked there is little risk of water flow into the heating circuit and less of water flow from the heating circuit into the mains supply. In this first embodiment the device comprises, connected in order along the flow pathway: a 15 mm inlet compression to 8 mm ball valve 12, an 8 mm push button water valve 14, a 15 mm to 8 mm adapter 26, a 15 mm flexible filling link comprising a metal braided hose 16 and a 15 mm combined double check and ball valve 24.

[0051] The second embodiment of the fill loop device is generally similar to the first and corresponding components are identified with similar numerals. Accordingly only the differences will be described. As can best be seen in FIGS. 3A and 3B the filling loop device includes a governor or pressure regulating valve 25 in series with the press button valve 14. The pressure regulating valve 25 is set to limit the maximum water supply pressure at the outlet 6 of the filling loop device to correspond to the specified maximum pressure for the boiler 1. As a result an inexperienced or untrained user cannot over pressurise the system and thereby cause damage.

[0052] A further modification of the second embodiment is most readily apparent from FIG. 3C. This addresses the issue of the isolation valve 18 being incorrectly left open and permitting backflow to the press valve 14 even against the check valve 22. Against this eventuality a drain passage 14k is formed in the lower part of the spool and arranged to align with the outlet port. The drain passage 14k is isolated from the through passage by a barrier 14p, and the middle “O” ring 14m″. The drain passage communicates with a lower part of the spool chamber and hence to a drain port 14j is provided in the body of the press valve 14. The drain port is conveniently formed by drilling a bore 14m through the base 14n of the spool chamber. Since the lower part of the spool chamber is then open to air this creates an air gap between the inlet port and the outlet port. A hollow nipple 14o may be formed on the spool chamber base in communication with the bore 14m to which a hose may be attached. This allows water flowing back into the press valve (from the right in FIG. 3C, to flow through a drain port 14k formed in a bottom portion of the spool 14f and to drain out through the drain port 14j.

[0053] FIG. 3C illustrates an alternative embodiment in which the spring 14e′ shown in ghosted lines, is located around the press button stem to act between the press button and the valve nut 15b.

[0054] Referring to FIG. 4A the dead-man valve and pressure regulator valve are combined in a single unitary structure 30 which has an inlet port 31 and outlet port 32. The inlet port 31 may be directly connected to the mains water supply 3, preferably via an isolation check valve such as 4 in the previous embodiments, similarly the outlet port 32 can be directly connected to the heating circuit via the an isolation check valve such as previously described at 6. The regulator valve 30 has a pressure set screw 33 to set the maximum pass pressure for the valve and will commonly be pre-set according to the manufacturers specifications for the heating system. The press button of the previous embodiments is replaced by a rotatable knob 34.

[0055] The inlet port 31 communicates with a first chamber 35. This is closed by an annular bulkhead 36. The lumen 37 of the bulkhead 36 is closed by a piston valve seat 38 which can move in the vertical axial direction of the figures. Fluid sealing is achieved via an O ring seal 39, and the piston valve seat 38 is normally urged towards a closed and sealed condition, as shown in FIG. 4C by the action of a piston valve seat coil spring 40 which acts between the piston valve seat and bulkhead. This action presses the piston valve seat to sealingly engage a poppet or needle valve 41.

[0056] The poppet valve 41 is in turn urged up to engage the piston valve seat 38 by the action of a poppet valve compression spring 42 acting between the valve casing and the poppet valve 41. A cam 43 is mounted on a shaft 44 which is sealingly journaled to extend through the casing to irottatably engage rotary knob 34. The cam 43 may be constrained to rotate no more than the positions illustrated in order to retain the piston valve seat 38 against the action of the piston valve seat spring 40. Thus in the stopped condition shown in FIG. 4c no water can flow from the inlet chamber 35 to an outlet chamber 45 above the bulkhead.

[0057] As with conventional regulator valves, the outlet chamber 45 is sealed by a piston 46 which is connected to the poppet valve 41 by a con-rod 47. The piston 47 is urged down into the outlet chamber by the action of a piston spring 48 preloaded by the set screw 33.

[0058] To charge the heating circuit or boiler the knob 34 is rotated to the position shown in FIG. 4D. This rotates the cam 41 to press the piston valve seat 38 up against the action of the spring 40. Water can now flow between the poppet valve 41 and the piston valve seat 38 into the outlet chamber 45 and so to the outlet 32.

[0059] If the pressure in the outlet chamber rises excessively the force applied to the piston 46 causes the piston 46 to rise carrying the poppet valve towards the piston valve seat 38 and causing the pressure in the outlet chamber 45 to drop. If the knob 34 is released the piston valve seat spring 40 presses the piston valve seat down against the cam 41. The rotary axis of the cam 41 is arranged offset such that this induces a moment arm which rotates the cam back towards the closed condition. Thus the dead-man regulator valve cannot be left open unattended.

[0060] In a further variant of third embodiment check valves may be installed in the inlet and/or outlets 31, 32.

[0061] The operation of the third embodiment is substantially similar to the operation of the second embodiment.

[0062] It will be appreciated by the skilled person that while the filling loop device has been developed mainly for retrofit to existing pressurised boiler heating installation, it may be integrated into a boiler housing at manufacture, especially in the case of the second or third embodiments.

[0063] It will be understood that any features described in relation to any one embodiment may where reasonable, be technically feasible, be combined with any other described embodiments.

[0064] The invention may be further defined by the following clauses:

[0065] A filling device for a pressurised heating circuit comprising the following components connected in series to define a fluid flow path through them:

[0066] an inlet connector,

[0067] an inlet isolation valve,

[0068] a push button valve configured to open the fluid flow pathway when the button is pushed and to close it when the button is released,

[0069] a flexible tubing portion,

[0070] a check valve, connected such that flow from the inlet connector to an outlet connector is allowed while the reverse flow is prevented, and an outlet connector.

[0071] A device according to the immediately preceding paragraph wherein the check valve is a double check valve.

[0072] A device according to either of the two immediately preceding paragraphs comprising a second isolation valve connected to the check valve.

[0073] A device according to any one of the three preceding paragraphs wherein a check valve and an isolation valve are provided in the same housing.