WO2023046694A1

WO2023046694A1 - Apparatus and method for supplying liquid to a fluid circuit of a heating or a cooling system

Info

Publication number: WO2023046694A1
Application number: PCT/EP2022/076124
Authority: WO
Inventors: Darren Wilkinson; Paul Hanrahan
Original assignee: Vexo International (Uk) Ltd
Priority date: 2021-09-27
Filing date: 2022-09-20
Publication date: 2023-03-30
Also published as: GB202113758D0; GB2611081A

Abstract

Apparatus (101) for, and a method (701) of, supplying a liquid to a fluid circuit of a heating or a cooling system (102). First and second valves (311, 312) respectively control a flow of liquid from an inlet port (203) to an outlet port (204) of a fluid conduit arrangement (201) of the apparatus (101), and a flow of liquid through a drain port (205) of the fluid conduit arrangement (201). When the pressure level of the fluid circuit is at a desired pressure level, the valves (311, 312) are maintained in a first arrangement for restricting a flow of liquid from a liquid source (206) to the outlet port (204) and allowing a flow of liquid through the drain port (205), otherwise the valves (311, 312) are maintained in a second, different arrangement for allowing a flow of liquid from the liquid source (206) through the outlet port (204).

Description

APPARATUS AND METHOD FOR SUPPLYING LIQUID TO A FLUID CIRCUIT OF A HEATING OR A COOLING SYSTEM

Field of the Invention

The present invention relates to fluid circuit filling, in particular to apparatus for and a method of supplying liquid to a fluid circuit of a heating or a cooling system, and also to maintaining a level of liquid in the fluid circuit of the heating or the cooling system.

Background of the Invention

Heating systems and cooling systems are known that comprise a fluid circuit through which a fluid circulates under pressure. An example of this type of system is a closed-circuit central heating system, in which system water flows in a loop from a boiler, through a series of hot-water radiators, and then back to the boiler. The system water may comprise a treatment additive, for example to reduce corrosion and/or to inhibit microbiological growths (bacteria or fungi), in addition to water, which may be supplied from a mains water supply.

When a system is connected to a mains water supply, it is desirable to prevent backflow, to avoid treated or contaminated water from entering the mains water supply. A way of achieving this involves utilising a “break” in the fluid flow path between the mains water supply and the fluid circuit. This may be provided by a water tank having an inlet connected to the water supply, an outlet connected to the fluid circuit, and a float-operated valve or other suitably controlled valve for selectively allowing water to flow from the mains into the water tank.

It is desirable to provide an improved arrangement for supplying liquid to a fluid circuit of a heating or a cooling system.

Summary of the Invention

According to a first aspect there is provided apparatus for supplying a liquid to a fluid circuit of a heating or a cooling system, the apparatus comprising: a fluid conduit arrangement having an inlet port for receiving liquid from a liquid source, and an outlet port for supplying liquid to the fluid circuit, the fluid conduit arrangement defining a first flow path between the inlet port and the outlet port, and the fluid conduit arrangement further comprising a drain port, disposed between the inlet port and the outlet port, the fluid conduit arrangement defining a second flow path between the first flow path and the drain port; a first valve movable between a closed condition and an open condition for controlling a flow of liquid from the inlet port to the outlet port, a second valve movable between a closed condition and an open condition for controlling a flow of liquid through the drain port; a controller comprising a non-transitory computer-readable medium and program instructions stored on the non-transitory computer-readable medium that are executable by the controller to cause the controller to: (a) during a non-filling mode of operation, maintain the first valve in a closed condition and maintain the second valve in an open position, whereby a flow of liquid from the inlet port to the outlet port is restricted and a flow of liquid through the drain port is allowed; and (b) (i) upon detecting a trigger to enter a filling mode of operation, cause the second valve to be moved from the open condition into the closed condition, and cause the first valve to be moved from the closed condition into the open condition, whereby to allow a flow of liquid from the inlet port through the outlet port; and (b) (ii) upon detecting a trigger to exit the filling mode of operation and return to the non-filling mode of operation, cause the first valve to be moved from the open condition into the closed condition, and cause the second valve to be moved from the closed condition into the open condition, whereby to restrict a flow of liquid from the fluid source to the outlet port and allow a flow of liquid through the drain port.

The apparatus beneficially serves to avoid undesirable effects being encountered from water being left stagnant. The apparatus also advantageously provides an air gap between the liquid source and the fluid circuit (“air-break”), which is maintained during a non-filling state until the filling routine is again activated. Another beneficial aspect is that the apparatus is arranged such that in the event of a loss of electricity, the second valve remains open so that over-pressurising of the fluid circuit is avoided. Further, the apparatus advantageously controls the pressure and flow rate to the fluid circuit without the use of a pump arrangement, which would require regular inspection and maintenance/servicing and could fail, and advantageously supplies fluid to the fluid circuit without the use of a vessel arrangement, which would need to be physically accommodated and could provide an environment that would allow bacteria to proliferate.

The apparatus may further comprise a membrane filter and a UV sterilizer arranged so that a flow of liquid through the fluid conduit arrangement to the outlet port passes through the membrane filter and the UV sterilizer before exiting the outlet port. The membrane filter may be upstream of the UV sterilizer. The controller may be operable to selectively switch the UV sterilizer between an on condition and an off condition and the program instructions stored on the non-transitory computer-readable medium may be executable by the controller to cause the controller to: during the non-filling mode of operation, maintain the UV sterilizer in an off condition; and during the filling mode of operation, maintain the UV sterilizer in an on condition.

The membrane filter and the UV sterilizer may both be enclosed in a housing of the apparatus. Alternatively, the membrane filter may be located externally of the housing and the UV sterilizer may be enclosed within the housing.

The outlet port may be separate from the inlet port and the drain port may be separate from the inlet port and the outlet port.

The apparatus may further comprise an air vent.

The apparatus may further comprise a water hammer arrester.

The program instructions stored on the non-transitory computer-readable medium may be executable by the controller to cause the controller to: determine the amount of liquid that has passed through the apparatus during a particular period. The apparatus may further comprise a flow restrictor and a clock device, and the amount of liquid may be determined by a calculation based on a flow rate associated with the flow restrictor and a duration of operation of the apparatus. The apparatus may further comprise a dosing pump arrangement comprising a dosing valve for supplying an additive to a fluid circuit of the heating or the cooling system, and the program instructions stored on the non-transitory computer-readable medium may be executable by the controller to further cause the controller to: output a signal to the dosing pump arrangement to execute dosing of the additive to the fluid circuit.

The dosing valve may be a proportional dosage valve and the signal may be a pulse signal for executing proportional dosing of the additive. The dosing valve may be upstream of the outlet port.

According to a second aspect there is provided a heating or a cooling system comprising the apparatus of the first aspect.

According to a third aspect there is provided method of supplying liquid to a fluid circuit of a heating or a cooling system, comprising the steps of: (a) receiving apparatus comprising a fluid conduit arrangement comprising an inlet port, an outlet port separate from the inlet port and a drain port separate from the inlet port and separate from the outlet port, and further comprising a controller, a pressure sensor, a first valve, and a second valve; (b) connecting the inlet port of the fluid conduit arrangement to a liquid source and connecting the outlet port to the fluid circuit of the heating or the cooling system, (c) determining whether a pressure level of the fluid circuit sensed by the pressure sensor is at or below a desired pressure level; and (d) (i) in response to determining at step (c) that the pressure level of the fluid circuit is at a desired pressure level, maintaining the first valve and the second valve in a first valve arrangement for restricting a flow of liquid from the liquid source to the outlet port and allowing a flow of liquid through the drain port; and (d) (ii) in response to determining at step (c) that the pressure level of the fluid circuit is below a desired pressure level, maintaining the first valve and the second valve in a second, different valve arrangement for allowing a flow of liquid from the liquid source through the outlet port.

The apparatus may further comprise a membrane filter and a UV sterilizer and, during step (d) (ii), a flow of liquid through the fluid conduit arrangement to the outlet port may pass through the membrane filter and the UV sterilizer before exiting the outlet port. The membrane filter may be located upstream of the UV sterilizer.

The apparatus may further comprise a dosing pump arrangement comprising a dosing valve for supplying an additive to a fluid circuit of the heating or the cooling system, and during step (d) (ii), a flow of liquid through the outlet port may contain additive supplied from the dosing valve.

The liquid source may be a cold mains water supply or pre-treated water supply.

Further particular and preferred aspects of the invention are set out in the accompanying dependent claims.

Brief Description of the Drawings

The present invention will now be more particularly described, with reference to the accompanying drawings, in which:

Figure I shows a schematic of apparatus for supplying liquid to a fluid circuit of a heating or a cooling system, according to the present application, operatively connected to a fluid circuit of a heating system;

Figure 2 shows a diagram of the apparatus for supplying liquid to a fluid circuit of a heating or a cooling system of Figure I ;

Figure 3 illustrates a first example arrangement of an apparatus for supplying liquid to a fluid circuit of a heating or a cooling system, according to the present application;

Figures 4 & 5 illustrate a second example arrangement of an apparatus for supplying liquid to a fluid circuit of a heating or a cooling system, according to the present application;

Figure 6 illustrates elements utilised in optional additional functionality of a controller of an apparatus according to the first example arrangement of Figure 3 or the second example arrangement of Figures 4 & 5; and

Figure 7 shows steps in a method of supplying liquid to a fluid circuit of a heating or a cooling system. Description

Illustrative embodiments and examples are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the apparatus described herein. It is to be understood that embodiments and examples can be provided in many alternate forms and the invention should not be construed as limited to the embodiments and examples set forth herein but by the scope of the appended claims.

Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. In addition, features referred to herein in the singular can number one or more, unless the context clearly indicates otherwise. Similarly, the terms “comprises”, “comprising”, “includes”, “including”, “has” and/or “having” when used herein, specify the presence of the stated feature or features and do not preclude the presence or addition of one or more other features, unless the context clearly indicates otherwise.

In the following description, all orientational terms, such as upper, lower, radially and axially, are used in relation to the drawings and should not be interpreted as limiting on the invention, unless the context clearly indicates otherwise.

The drawings are not necessarily drawn to scale, and in some instances the drawings may have been exaggerated or simplified for illustrative purposes only.

The present application provides an apparatus for supplying liquid to a fluid circuit of a heating or a cooling system. The apparatus, which is usable as a fully automated pressurisation system for use in domestic and commercial closed-loop heating and cooling systems, comprises an integrated water treatment arrangement, with a “double-function” achieved by utilising two different improvement mechanisms, preferably a filter and a UV sterilizer. The present application further provides a method of supplying liquid to a fluid circuit of a heating or a cooling system. Mains water typically contains low levels of bacteria (non-pathogenic); however, these low levels of bacteria can proliferate at a logarithmic rate within a sealed system. The system of the present application functions to prevent any bacteria from entering the fluid circuit.

As will be described in further detail, the present invention provides apparatus for, and a method of, supplying a liquid to a fluid circuit of a heating or a cooling system. First and second valves respectively control a flow of liquid from an inlet port to an outlet port of a fluid conduit arrangement of the apparatus, and a flow of liquid through a drain port of the fluid conduit arrangement. When the pressure level of the fluid circuit is at a desired pressure level, the valves are maintained in a first arrangement for restricting a flow of liquid from a liquid source to the outlet port and allowing a flow of liquid through the drain port, otherwise the valves are maintained in a second, different arrangement for allowing a flow of liquid from the liquid source through the outlet port.

Apparatus 101 for supplying liquid to a fluid circuit of a heating or a cooling system is shown in Figure I , connected to a fluid circuit of a heating system 102. In this illustrated example, the heating system 102 is a hot water circulation system, which may be in a residential or commercial building. The heating system 102 comprises a heat source 103, in this example a boiler, and at least one heat emitter 104, in this example a radiator. The heating system 102 further comprises a main system flow pipe 105 for receiving fluid from the heat source 103, and by means of which circulating system fluid is carried from the heat source 103 to the at least one heat emitter 104, and a main system return pipe 105 for supplying fluid to the heat source 103, and by means of which circulating system fluid is delivered from the at least one heat emitter 104 to the heat source 103.

The apparatus 101 is shown installed close to the heating system 102, and upstream of a system expansion vessel 107 that is connected to the heat source 103.

Apparatus 101 is usable to supply a liquid from a liquid source to the fluid circuit, and in the arrangement shown in Figure I the apparatus 101 is installed for supplying a top-up liquid to the fluid circuit of the heating system 102. Referring now to Figure 2, the apparatus 101 comprises a fluid conduit arrangement 201 , which in this example is supported by a housing 202.

The apparatus 101 comprises an inlet port, indicated at 203, an outlet port, indicated 204, and a drain port, indicated at 205. The outlet port 204 is separate from the inlet port 205, and the drain port 205 is separate from the inlet port 203 and likewise the outlet port 204. The inlet port 203 is provided for receiving liquid from a liquid source 206, in the present example water from a mains water supply. The outlet port 204 is provided for supplying liquid from the fluid conduit arrangement 201 to a fluid circuit, in the present example to the fluid circuit of heating system 102. The drain port 205 is disposed between the inlet port 203 and the outlet port 204.

The fluid conduit arrangement 201 provides a first “filling” flow path, for use when supplying top-up liquid to the fluid circuit of heating system 102, and a second “draining” flow path.

The “filling” flow path extends generally between the inlet portion 203 and the outlet port

204. A junction 207 along the “filling” flow path is indicated. The “draining” flow path extends generally between the “filling” flow path and the drain port 205.

A first flow region 208, extending from the inlet port 203 to the junction 207, and a second flow region 209, extending from the junction 207 to the outlet port 204, are indicated. A third flow region 210 is indicated, which extends from the junction 207 to the drain port

205.

The apparatus for supplying liquid to a fluid circuit of a heating or a cooling system as disclosed herein incorporates a fluid treatment function, to treat received fluid before delivery to the fluid circuit. A first fluid treatment aspect involves a physical filtration stage. A second fluid treatment aspect involves a UV light sterilisation stage.

In an embodiment, a physical filtration stage is provided upstream of a UV light sterilisation stage. The apparatus will now be described further with reference to the example arrangements of Figure 3 and of Figures 4 & 5.

A simplified hydraulic schematic of a first embodiment 301 of an apparatus for supplying liquid to a fluid circuit of a heating or a cooling system as disclosed herein is illustrated in Figure 3.

As shown, the first embodiment 301 comprises fluid conduit arrangement 201 , with inlet port 203, outlet port 204, drain port 205, as described with reference to Figure 2.

In this specific example, the first flow region 208, extending from the inlet port 203 to junction 207, comprises a first branch 302, extending between the inlet port 203 and a node 303, and a second branch 304, extending between the node 303 and the junction 207. The second flow region 209, extending from the junction 207 to the outlet port 204, comprises a first branch 305, extending between the junction 207 and a node 306, and a second branch 307, extending between the node 306 and the outlet port 204. The third flow region 210 comprises a branch 308, extending between the junction 207 and the drain port 205. The first branch 302 of the first flow region 208, the second branch 307 of the second flow region 209 and the branch 308 of the third flow region 210 extend in parallel, and the second branch 304 of the first flow region 208 and the first branch 305 of the second flow region 209 extend in series, linearly between the nodes 303, 306 (with the pathway therebetween including junction 207).

In this specific example, a first pressure transducer 309 is disposed downstream of the inlet port 203, along the “filling” flow path, more specifically between the inlet port 203 and the junction 207, and in the shown arrangement along the first branch 302 of the first flow region 208. A second pressure transducer 310 is upstream of the outlet port 204, along the “filling” flow path, more specifically between the junction 207 and the outlet port 204, and in the shown arrangement along the second branch 307 of the second flow region 209.

A first valve 3 I I , in this embodiment a solenoid valve, is disposed downstream of the inlet port 203, along the “filling” flow path, more specifically between the inlet port 203 and the junction 207, and in the shown arrangement along the second branch 304 of the first flow region 208. A second valve 312, in this embodiment a solenoid valve, is disposed downstream of the inlet port 203, along the “draining” flow path, more specifically between the junction 207 and the draining port 205, along the branch 308 of the third flow region 210.

Also shown are a non-return valve 313, located upstream of the first pressure transducer 309, and a second non-return valve 314, located upstream of the second pressure transducer 310.

Also identified are a membrane filter 315 and a UV sterilizer 316. In this specific example, both the membrane filter 315 and the UV sterilizer 316 are enclosed within the housing 202 of the apparatus.

As shown, the membrane filter 315 is located upstream of the UV sterilizer 316, along the “filling” flow path. In this illustrated example, the membrane filter 315 and the UV sterilizer 316 are both disposed along the second flow region 209, between the junction 207 and the outlet 204, more specifically along the second branch 307 of the second flow region 209.

Also shown is a third non-return valve 317, located upstream of the membrane filter 315.

Further indicated are an optional water hammer arrestor 318, shown fluidly connected to the fluid conduit arrangement 201 at node 303, and also an air vent 319, shown fluidly connected to the fluid conduit arrangement 201 at junction 207. The water hammer arrestor 318 and air vent 319 are positioned at a top end 320 of the fluid circuit arrangement. A water hammer arrestor arrangement immediately before the first valve 3 I I serves to protect against damage that may arise from sudden pressure changes.

The apparatus further comprises a controller 321 for controlling operation of the apparatus. The controller 321 comprises a non-transitory computer-readable medium and program instructions stored on the non-transitory computer-readable medium that are executable by the controller to cause the controller to perform various functions. The controller 321 may be any suitable device, for example a programmable logic controller (PLC). The controller 321 receives input signals from, and outputs signals to, other electrical components of the apparatus, as indicated by arrow 322. Preferably, the apparatus also comprises a display device 323 that comprises a display screen. The display device may comprise a user input module, allowing a user to input selections and/or access data and/or change parameters (for example, allowing a user to adjust operational controls and/or view recorded fault codes etc.). The display device may also comprise a communication module, allowing wired and/or wireless communication therewith, which may be one-way or two-way (for example, to allow a user to view data and/or effect control remotely, or to transfer data to and/or from the display device). Preferably, the controller 321 receives input signals from and/or outputs signals to, other electrical components that are external of the apparatus 101 , as indicated by arrow 324.

The controller is configured to detect a trigger to enter a filling mode of operation (from a non-filling mode of operation), and to perform functions associated therewith, and to detect a trigger to enter a non-filling mode of operation (from a filling mode of operation), and perform functions associated therewith,

The controller is configured to selectively cause each of the first valve and the second valve to be opened and closed.

In a preferred example, the controller is configured to selectively switch the UV sterilizer between an on condition and an off condition. For example, it is desirable for the UV sterilizer to be powered on when the apparatus is entering a filling mode and turned off when the apparatus is exiting the filling mode, to improve energy efficiency.

The controller may be utilised in the provision of one or more other functions, and preferably incorporates the ability to detect: a pressure fault condition, a filter status fault condition, a UV sterilizer fault condition. The apparatus functions to inhibit bacteria, which may be present in received liquid, from entering the fluid circuit. The apparatus also functions to inhibit particles over a particular size, which may be present in received liquid, from entering the fluid circuit. The filtration also serves to prevent shadowing, which is detrimental to UV efficacy. The apparatus effects a “double treatment” of received liquid, using the arrangement of a membrane filter followed by the UV sterilizer.

In the present example, the apparatus is a non-supplying state (“non-filling” mode of operation) unless a supplying routine (“filling” mode of operation) is initiated, for supplying liquid to a fluid circuit. When the apparatus is in a non-filling mode, the first valve and the second valves are maintained in a first valve arrangement (first valve closed, second valve open) and when the apparatus is in a filling mode, the first valve and the second valves are maintained in a second, different valve arrangement (first valve open, second valve closed).

When in the non-filling mode of operation, the first valve 3 I I is closed, and the second valve 312 is open. There is no flow through the apparatus, and system liquid in the fluid circuit of the heating or cooling system is circulated.

Over time, pressure loss in the fluid circuit results in a requirement for re-pressurisation. The pressure in the fluid circuit is monitored by the second pressure transducer 310 (which is upstream of the outlet port 204). It is to be appreciated that the pressure in the fluid circuit may be acceptable when within a range of pressure values rather than when only at a single pressure value.

Upon the detection of a pressure that is lower than a desired pressure value of the fluid circuit, which can be defined during installation of the apparatus and which in this example is the lowest value of a range of pressure values, a supplying routine is initiated, and the apparatus enters the filling mode.

The second valve 312 is closed and the first valve 3 I I is opened, which allows a flow of liquid from the liquid source 206 into the fluid conduit arrangement 201 , through the inlet port 203. Liquid received from the liquid source 206 must pass through the membrane filter 315 and then through the UV sterilizer 316, which are arranged in series, before exiting the outlet port 204 for the fluid circuit.

In an example, on entering the filling mode, the second valve 312 is moved into the closed condition before the first valve 3 I I is moved into the open condition.

The air vent 319, which is positioned at the top 320 of the fluid conduit arrangement 201 , downstream of the first valve 31 I and upstream of the second valve 312, functions to remove air when the fluid circuit is being pressurised.

The pressure in the fluid circuit continues to be monitored by the second pressure transducer 310 during the filling mode. Upon the detection of a pressure that is equal to or greater than a desired pressure value of the fluid circuit, which can be defined during installation of the apparatus and which in this example is the highest value of the range of pressure values, the apparatus terminates the supplying routine and exits the filling mode.

The first valve 3 I I is returned to its normally closed condition, and the second valve 312 is returned to its normally open condition, allowing received liquid to drain from the fluid conduit arrangement 201. This beneficially serves to avoid undesirable effects of water being left stagnant being encountered. The apparatus also advantageously provides an air gap between the liquid source and the fluid circuit, which is maintained until the filling routine is again activated. The provision of such an “air-break” is a feature of water regulations in the UK (and other jurisdictions).

In an example, on exiting the filling mode, the first valve 3 I I is moved into the closed condition before the second valve 312 is moved into the open condition.

Furthermore, the draining feature facilitates maintenance and fault diagnosis.

As the second valve 312 is normally open, if the first valve 31 I fails then liquid from the liquid source 206 will leak through the drain port 205. The provision of a tundish 325 at the drain port 205 enables quick and easy visual detection of such a fault. Advantageously, in the event of a loss of electricity the second valve 312 remains open to avoid overpressurising of the fluid circuit.

Further, the first pressure transducer 309 monitors the supply pressure. Upon the detection of a pressure that is lower than a desired supply pressure value which can be defined during installation of the apparatus, a supply pressure fault signal is output to the controller 321 .

It is to be appreciated that the apparatus advantageously controls the pressure and flow rate to the fluid circuit without the use of a pump arrangement, which would require regular inspection and maintenance/servicing and could fail. It is further to be appreciated that the apparatus advantageously supplies fluid to the fluid circuit without the use of a vessel arrangement, which would need to be accommodated within the overall dimensions of the apparatus and could provide an environment that would allow bacteria to proliferate.

A simplified hydraulic schematic of a second example arrangement 401 of an apparatus for supplying liquid to a fluid circuit of a heating or a cooling system as disclosed herein is illustrated in Figure 4. Another illustration of the second example arrangement 401 is shown in Figure 5.

A difference between the second embodiment 401 and the first embodiment 301 will now be described.

In the first embodiment 301 , both the membrane filter 315 and the UV sterilizer 316 are enclosed within the housing 202. In the second embodiment 401 , the UV sterilizer 316 is enclosed within the housing 202 but the membrane filter 315 is not; in the specific illustrated arrangement, the membrane filter 315 is located externally of the housing 202 and connected to the inlet port 204, by the housing 202. In the shown arrangement, therefore, the membrane filter 315 is upstream of the inlet port 203. The membrane filter 315 is still upstream of the UV sterilizer 316, and liquid flowing from the inlet port 203 to the outlet port 204 must still pass through the membrane filter 315 and then the UV sterilizer 316. The first embodiment 301 relates to an “internal membrane filter” design and the second embodiment relates to an “external membrane filter” design.

The first embodiment 301 , with the membrane filter located within the housing, is recommended for applications in which access to the componentry of the apparatus is to be restricted.

The second embodiment 401 , with the membrane filter located outside the housing, is recommended for applications in which access to the componentry of the apparatus does not need to be so restricted.

It is to be understood that the apparatus may comprise other components in addition to those illustrated and already discussed. For example, a pressure reduction valve arrangement may be utilised on the inlet 201 , which may be desirable depending on municipal pressure conditions (if a mains water supply is used).

Features of an apparatus as described above that assist fault prevention and convenient maintenance include:

- The second valve allowing the system to be drained so that maintenance technicians can access the apparatus dry.

- The second valve being normally open; in the event of a loss of electricity the apparatus does not pressurise the fluid circuit of the heating or cooling system.

- The air vent allows trapped air to escape, ensuring the apparatus remains functional.

- The first pressure transducer being used to signal the controller in the event of a supply pressure fault.

The membrane filter may be any suitable type. The membrane filter functions to physically separate particles that are equal or greater than a particular size from the flow of liquid, to remove such particles from the liquid being supplied, via the UV sterilizer, to the outlet port, and hence improve the quality of the liquid supplied to the fluid circuit of the heating or cooling system.

The UV sterilizer may be any suitable type. The UV steriliser functions to emit ultraviolet light on the flow of liquid, to destroy bacteria in the liquid being supplied to the outlet port, and hence improve the quality of the liquid supplied to the fluid circuit of the heating or cooling system.

Optional additional functionality of the controller 321 will now be described with reference to Figure 6.

As mentioned previously, the controller 321 receives input signals from, and outputs signals to, other electrical components of the apparatus 101 , as indicated by arrow 322.

The controller 321 may monitor the use/amount of water that has passed through the apparatus 101 during a particular period.

In an example, the program instructions stored on the non-transitory computer-readable medium are executable by the controller to cause the controller to: determine the amount of liquid that has passed through the apparatus during a particular period.

The amount of liquid that that has passed through the apparatus during a particular period may be determined by calculation based on a flow rate associated with a flow restrictor 601 of the apparatus 101 and a duration of operation of the apparatus 101 , which may be derived from a suitable clock device, which may be an internal timer 602 of the controller 321. The controller 321 may determine an amount of liquid that has passed through the apparatus 101 during a particular period that may be one of: a filling instance, a fixed period of days, weeks, months etc., the time since a volume counter was reset to zero.

The controller 32 I may control operation of a dosing pump arrangement 603 comprising a dosing valve 604 for supplying an additive 605 to the fluid circuit. In a preferred example, the controller is configured to selectively switch the dosing pump arrangement between an on condition and an off condition.

In an application, the dosing valve 604 is upstream of the outlet port 204, to allow liquid to be dosed with the additive before entering the fluid circuit. Thus, dosing pump arrangement 603 may be powered on when the apparatus is entering a filling mode and turned off when the apparatus is exiting the filling mode.

In an example, the program instructions stored on the non-transitory computer-readable medium are executable by the controller to further cause the controller to: output a signal to the dosing pump arrangement to execute supply of the additive to the fluid circuit.

In an example, the dosing valve is a proportional dosage valve. The signal may then be a pulse signal for executing proportional dosing of the additive.

The additive may be any suitable chemical or combination of chemicals. In an example, the additive is Glycol.

Other elements may be utilised in providing the same and/or other optional additional functionality of a controller of an apparatus for supplying a liquid to a fluid circuit of a heating or a cooling.

Steps in a method 701 of supplying a liquid to a fluid circuit of a heating or a cooling system, using the apparatus described herein, are shown in Figure 7.

At step 702, the apparatus is in a non-filling mode and the supply of liquid to the outlet port from the inlet port is prevented. As described previously, the first valve is closed, to restrict a flow of liquid from the inlet port, and the second valve is open, to allow a flow of liquid through the drain port; with this valve arrangement, the presence of an air-break between the inlet port and the outlet port and the drain port being open prevents liquid being supplied to the outlet port. At step 703, a question is asked as to whether a supplying routine is to be activated. As described previously, the second pressure transducer monitors the pressure in the fluid circuit. Upon detecting a pressure level is below a desired pressure level, the apparatus enters a filling mode, otherwise the apparatus will remain in the non-filling mode. Hence, if the question asked at step 703 is answered in the negative, step 702 is re-entered, but if the question asked at step 703 is answered in the affirmative, step 704 is entered.

At step 704, the apparatus is in a filling mode and the supply of liquid to the outlet port from the inlet port is allowed. As described previously, the first valve is opened, to allow a flow of liquid from the inlet port, and the second valve is closed, to prevent a flow of liquid through the drain port; with this valve arrangement, the absence of an air-break between the inlet port and the outlet port and the drain port being closed allows liquid to be supplied to the outlet port. As also described previously, the liquid supplied to the outlet port, for filling the fluid circuit of the heating or cooling system, is treated as it flows from the liquid source to the outlet port, by the membrane filter and the UV sterilizer.

At step 705, a question is asked as to whether the supplying routine is to be deactivated. As described previously, the second pressure transducer monitors the pressure in the fluid circuit. Upon detecting a pressure level that is a desired pressure level (this being either an absolute value or a value within a range of acceptable values), the supplying routine is no longer required to be in operation, the apparatus exits the filling mode, otherwise the apparatus will remain in the filling mode. Hence, if the question asked at step 705 is answered in the negative, step 704 is re-entered, but if the question asked at step 703 is answered in the affirmative, step 702 is entered.

Thus, a comparison of a measured pressure with a predetermined pressure is performed to determine whether to enter the filling mode from the non-filling mode and also to determine whether to enter the non-filling mode from the filling mode.

The method may include further steps relating to the filling/non-filling modes, or one or more other modes or processes. For example, the apparatus may comprise a dosing pump arrangement comprising a dosing valve for supplying an additive to a fluid circuit of the heating or the cooling system, and the method may comprise one or more steps relating to the provision of a flow of liquid through the outlet port that contains additive supplied from the dosing valve.

In accordance with the present invention, there is provided apparatus for supplying a liquid to a fluid circuit of a heating or a cooling system, the apparatus comprising: a fluid conduit arrangement having an inlet port for receiving liquid from a liquid source, and an outlet port for supplying liquid to the fluid circuit, the fluid conduit arrangement defining a first flow path between the inlet port and the outlet port, and the fluid conduit arrangement further comprising a drain port, disposed between the inlet port and the outlet port, the fluid conduit arrangement defining a second flow path between the first flow path and the drain port; a first valve movable between a closed condition and an open condition for controlling a flow of liquid from the inlet port to the outlet port, a second valve movable between a closed condition and an open condition for controlling a flow of liquid through the drain port; a controller comprising a non-transitory computer-readable medium and program instructions stored on the non-transitory computer-readable medium that are executable by the controller to cause the controller to:

(a) during a non-filling mode of operation, maintain the first valve in a closed condition and maintain the second valve in an open position, whereby a flow of liquid from the inlet port to the outlet port is restricted and a flow of liquid through the drain port is allowed; and

(b) (i) upon detecting a trigger to enter a filling mode of operation, cause the second valve to be moved from the open condition into the closed condition, and cause the first valve to be moved from the closed condition into the open condition, whereby to allow a flow of liquid from the inlet port through the outlet port; and

(b) (ii) upon detecting a trigger to exit the filling mode of operation and return to the non-filling mode of operation, cause the first valve to be moved from the open condition into the closed condition, and cause the second valve to be moved from the closed condition into the open condition, whereby to restrict a flow of liquid from the fluid source to the outlet port and allow a flow of liquid through the drain port.

In accordance with the present invention, there is provided a method of supplying liquid to a fluid circuit of a heating or a cooling system, comprising the steps of:

(a) receiving apparatus comprising a fluid conduit arrangement comprising an inlet port, an outlet port separate from the inlet port and a drain port separate from the inlet port and separate from the outlet port, and further comprising a controller, a pressure sensor, a first valve, and a second valve;

(b) connecting the inlet port of the fluid conduit arrangement to a liquid source and connecting the outlet port to the fluid circuit of the heating or a cooling system,

(c) determining whether a pressure level of the fluid circuit sensed by the pressure sensor is at or below a desired pressure level; and

(d) (i) in response to determining at step (c) that the pressure level of the fluid circuit is at a desired pressure level, maintaining the first valve and the second valve in a first valve arrangement for restricting a flow of liquid from the liquid source to the outlet port and allowing a flow of liquid through the drain port; and

(d) (ii) in response to determining at step (c) that the pressure level of the fluid circuit is below a desired pressure level, maintaining the first valve and the second valve in a second, different valve arrangement for allowing a flow of liquid from the liquid source through the outlet port.

The apparatus preferably comprises a membrane filter and a UV sterilizer, preferably in series with the UV sterilizer downstream of the membrane filter, whereby a flow of liquid through the fluid conduit from the liquid source to the outlet port passes through the membrane filter and the UV sterilizer before being supplied to the fluid circuit of a heating or cooling system.

The apparatus preferably comprises a dosing pump arrangement for dosing an additive, whereby a flow of liquid from the outlet port to the fluid circuit contains an amount of the additive. The apparatus preferably comprises a housing, the UV sterilizer is enclosed within the housing, and the membrane filter may be enclosed within the housing or located externally of the housing. Although illustrative embodiments and examples of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiment and examples shown and/or described and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims.

Claims

I . Apparatus for supplying a liquid to a fluid circuit of a heating or a cooling system, the apparatus comprising: a fluid conduit arrangement having an inlet port for receiving liquid from a liquid source, and an outlet port for supplying liquid to the fluid circuit, the fluid conduit arrangement defining a first flow path between the inlet port and the outlet port, and the fluid conduit arrangement further comprising a drain port, disposed between the inlet port and the outlet port, the fluid conduit arrangement defining a second flow path between the first flow path and the drain port; a first valve movable between a closed condition and an open condition for controlling a flow of liquid from the inlet port to the outlet port, a second valve movable between a closed condition and an open condition for controlling a flow of liquid through the drain port; a controller comprising a non-transitory computer-readable medium and program instructions stored on the non-transitory computer-readable medium that are executable by the controller to cause the controller to:

22

2. The apparatus of claim I , further comprising a membrane filter and a UV sterilizer wherein a flow of liquid through the fluid conduit arrangement to the outlet port passes through the membrane filter and the UV sterilizer before exiting the outlet port.

3. The apparatus of claim 2, wherein the membrane filter is upstream of the UV sterilizer.

4. The apparatus of claim 2 or claim 3, further comprising a housing, and wherein the membrane filter and the UV sterilizer are both enclosed within the housing.

5. The apparatus of claim 2 or claim 3, further comprising a housing, and wherein the membrane filter is located externally of the housing and the UV sterilizer is enclosed within the housing.

6. The apparatus of claims 2 to 5, wherein the controller is operable to selectively switch the UV sterilizer between an on condition and an off condition and the program instructions stored on the non-transitory computer-readable medium are executable by the controller to cause the controller to: during the non-filling mode of operation, maintain the UV sterilizer in an off condition; and during the filling mode of operation, maintain the UV sterilizer in an on condition.

7. The apparatus of any preceding claim, wherein the outlet port is separate from the inlet port and the drain port is separate from the inlet port and the outlet port.

8. The apparatus of any preceding claim, further comprising an air vent.

9. The apparatus of any preceding claim, further comprising a water hammer arrester.

10. The apparatus of any preceding claim, wherein the program instructions stored on the non-transitory computer-readable medium are executable by the controller to cause the controller to: determine the amount of liquid that has passed through the apparatus during a particular period.

I I . The apparatus of claim 10, further comprising a flow restrictor and a clock device, and said amount of liquid is determined by a calculation based on a flow rate associated with the flow restrictor and a duration of operation of the apparatus.

12. The apparatus of any preceding claim, further comprising a dosing pump arrangement comprising a dosing valve for supplying an additive to a fluid circuit of the heating or the cooling system, and wherein the program instructions stored on the non-transitory computer-readable medium are executable by the controller to further cause the controller to: output a signal to the dosing pump arrangement to execute dosing of the additive to the fluid circuit.

13. The apparatus of claim 12, wherein the dosing valve is a proportional dosage valve and the signal is a pulse signal for executing proportional dosing of the additive.

14. The apparatus of claim 12 or claim 13, wherein the dosing valve is upstream of the outlet port.

15. A heating or a cooling system comprising the apparatus of any preceding claim.

16. A method of supplying liquid to a fluid circuit of a heating or a cooling system, comprising the steps of:

(b) connecting the inlet port of the fluid conduit arrangement to a liquid source and connecting the outlet port to the fluid circuit of the heating or a cooling system, (c) determining whether a pressure level of the fluid circuit sensed by the pressure sensor is at or below a desired pressure level; and

17 The method of claim 16, wherein the apparatus further comprises a membrane filter and a UV sterilizer and, during step (d) (ii), a flow of liquid through the fluid conduit arrangement to the outlet port passes through the membrane filter and the UV sterilizer before exiting the outlet port.

18. The method of claim 17, wherein the membrane filter is located upstream of the UV sterilizer.

19. The method of any of claims 16 to 18, wherein the apparatus further comprises a dosing pump arrangement comprising a dosing valve for supplying an additive to a fluid circuit of the heating or the cooling system, and during step (d) (ii), a flow of liquid through the outlet port contains additive supplied from the dosing valve.

20. The method of any of claims 16 to 19, wherein the liquid source is a cold mains water supply or pre-treated water supply.

25