Abstract:
An apparatus for cleaning interior deposits and debris from a potable water heat exchanger, the apparatus having a first connector and a second connector. The first connector is mated with an outlet of a pump capable of pumping compressed fluid into the potable water heat exchanger without contaminating the compressed fluid and potable water. The second connector is mated with a fitting of the potable water heat exchanger. At least one connector having an associated valve.

Description:
[0001]    The present invention relates to an apparatus for cleaning deposits and debris from plumbing installations and in particular to an apparatus for cleaning deposits and debris from the potable water heat exchanger of a modern combination boiler. 
         [0002]    Combination boilers are boilers which incorporate all the components of a conventional system i.e. a pump, a diverter valve, its own heat exchanger for hot water. Combination boilers are sealed systems in that they have an expansion vessel built in to the boiler. This vessel, usually coloured red and round like in shape, is used for the expansion of water when the boiler heats the water. The vessel accommodates the extra volume the water has increased by. 
         [0003]    Combination boilers supply both heating and hot water. There is no need for a storage tank or stored hot water cylinder as the boiler creates instantaneous hot water at near mains pressure. Once a draw off for hot water is opened the boiler senses a signal from a flow switch which activates the burner. The heated non potable water created circulates through a secondary heat exchanger or direct hot water heat exchanger. This heated non potable water indirectly heats the cold potable water coming into the boiler. Once the cold potable water leaves the heat exchanger it is hot and is distributed via a hot water pipe which exits the boiler. 
         [0004]    Most plumbing installations gather build-ups of various kinds on the inner walls of their components and piping over time. Such build-ups can include dirt, debris, scale, calcification, and other mineral build-ups or foreign body impediments to the flow of water in the system. These build-ups effectively reduce the interior diameter of the components and pipes in question reducing the efficiency of the plumbed device or system as a whole. In addition, the deposits can break free and flow with the water, through the plumbing installation, turning up in outlets such as those which provide drinking or washing water where such contaminants are highly undesirable. 
         [0005]    It is also becoming increasingly important to increase the efficiency of plumbing installations such as boilers from a fuel consumption point of view. Cleaning of such components internally is possible with current commercially available solutions. Most of these solutions involve infusing the pipework of the boiler with chemical additives to breakdown the internal build-ups and return the boiler and supporting pipework to a more efficient condition. While this solution is effective, it cannot be used on a plumbing installation, or part thereof, where a portion of the pipework is used to carry fresh potable water for consumption, washing, or other activity having direct human contact as the chemical additives could be harmful in such a water supply. 
         [0006]    It may be assumed that forcing compressed fluid without the chemical additives would solve the aforementioned problem. However forcing fluid through the system using conventional compressors adds oil and other such substances into the plumbing installation which can infiltrate fresh water sections of the installation. 
         [0007]    It is an object of the present invention to obviate or mitigate the problem of clearing at least a portion of the interior build-up of deposits/debris within a potable water heat exchanger of a combination boiler without adding chemicals or other unwanted additives into the system. 
         [0008]    Accordingly, the present invention provides an apparatus for cleaning interior deposits and debris from a potable water heat exchanger, the apparatus comprising; 
         [0009]    a first connector and a second connector; 
         [0010]    the first connector being mateable with an outlet of a pump capable of pumping compressed fluid into the potable water heat exchanger without contaminating the compressed fluid and potable water; 
         [0011]    the second connector being mateable with a fitting of the potable water heat exchanger; 
         [0012]    at least one connector having valve means. 
         [0013]    Advantageously, the potable water heat exchanger is flushed with compressed fluid, clearing at least a portion of any build-ups in the potable water heat exchanger without contaminating the potable water heat exchanger with oil, other fluids, particulates, or any other foreign substances which would be considered highly undesirable in a fresh water supply. 
         [0014]    The air or gas is pumped into a first connector via a pump and passes through a conduit and on to a potable water heat exchanger. In this way, a volume of pressurized air or gas is pulsed through the water inside the potable water heat exchanger and some of the pressure is released by opening a faucet/tap or other suitable plumbing fitting. The sudden pulsing of the air or gas which has been pumped through the water in the potable water heat exchanger causes any water which is located inside the potable water heat exchanger to surge through the potable water heat exchanger. Some of the water and fluid will exit from the open faucet/tap or other fitting. This turbulent flow effect around and through the components of the potable water heat exchanger dislodges any discrepancies which have deposited on the internal surface of the potable water heat exchanger and these are flushed out of the system through the natural course of events. 
         [0015]    Ideally, the potable water heat exchanger is a secondary heat exchanger of a combination boiler. 
         [0016]    Preferably, the first and second connectors have a length of conduit therebetween. 
         [0017]    Ideally, the second connector comprising a valve. 
         [0018]    Preferably, the valve of the second connector is openable when the second connector is connected to the fitting of the potable water heat exchanger, and is closable when the connector is disconnected from the fitting of the potable water heat exchanger. 
         [0019]    Ideally, the first connector comprising a first valve which allows air or gas to flow in a direction from the first end of the conduit to the second end of the conduit. 
         [0020]    Preferably, the first connector is mateable with an outlet connector of an electrically driven pump. 
         [0021]    Ideally, the first connector is mateable with an outlet connector of a battery driven pump. 
         [0022]    Ideally, the pump power supply is 12V DC or a 240 V AC power supply. 
         [0023]    Preferably, the pump is a pump of the type that does not require lubrication by oil. Advantageously, this prevents oil contaminating the compressed fluid and therefore the fresh water supply of the potable water heat exchanger. 
         [0024]    Preferably, the second valve stops the flow of air or gas from the second connector when closed. 
         [0025]    Preferably, the second connector is mateable with a corresponding connector of the potable water heat exchanger. 
         [0026]    Ideally, the second connector is a female connector, mateable with a male connector of the potable water heat exchanger. 
         [0027]    Preferably, the potable water heat exchanger connector is a tap or faucet in fluid connection with the potable water heat exchanger. 
         [0028]    Preferably, the second connector is mateable with a threaded plumbing fitting having a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. 
         [0029]    In one embodiment, the second connector is mateable with a fitting of the potable water heat exchanger via an adapter. Preferably, the adapter is mateable with a threaded plumbing fitting having a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. 
         [0030]    Alternatively, the adapter is mateable with a faucet/tap of the plumbing fitting. The adapter may further comprise a valve which permits the flow of air or gas from the conduit to the potable water heat exchanger but which blocks the flow of fluid or gas from the potable water heat exchanger to the conduit. 
         [0031]    Preferably, the conduit is a tube. 
         [0032]    Ideally, the tube is formed of a flexible or rigid material. 
         [0033]    Preferably, the potable water heat exchanger is installed in one of: a residential property, a commercial property, a mobile or motorized home, a recreational vehicle (RV) or a boat. 
         [0034]    Ideally, the length of conduit further comprises a reservoir, between its first and second ends, the reservoir being capable of storing a quantity of pressurised gas. Advantageously, the reservoir can store a quantity of air or gas sufficient to urge water through the potable water heat exchanger. 
         [0035]    Preferably, the conduit further comprises a pressure sensor. 
         [0036]    Ideally, the pressure sensor is a mechanical sensor, such as a manometer. Alternatively, the pressure sensor may be an electronic sensor. 
         [0037]    Ideally, the fluid is water. 
         [0038]    Ideally, the pump is locatable within a dwelling or structure served by the potable water heat exchanger. 
         [0039]    Ideally, the pump is operable by a switch or other means of activation located within the dwelling or structure served by the potable water heat exchanger. 
         [0040]    Preferably, the switch or other means of activation couples the pump to a power supply. 
         [0041]    Alternatively, the pump comprises a charged canister containing pressurised gas, which can be discharged selectively by the operator. 
         [0042]    Ideally, the charged canister is chargeable/re-chargeable electronically by compressor. 
         [0043]    Alternatively, the charged canister can be chargeable/re-chargeable using a self inflating bladder contained within the charged canister. 
         [0044]    Preferably, the pump is fitted with a pressure sensor to measure the generated pressure of the fluid the pump is transferring. 
         [0045]    Ideally, the pump has limiter switch means to switch the pump off or on at a predetermined pressure level. 
         [0046]    Preferably, the limiter switch has an upper limit of approximately 30 psi. 
         [0047]    Advantageously, the pressure is not high enough to damage the potable water heat exchanger or components thereof but is high enough to move or dislodge deposits, debris, or other material within the potable water heat exchanger. 
         [0048]    Preferably, the pressure sensor is a mechanical sensor, such as a manometer. Alternatively, the pressure sensor may be an electronic sensor. 
         [0049]    Ideally, the fitting has a connector protruding from the potable water heat exchanger. 
         [0050]    Preferably, the connector is a threaded plumbing fitting having a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. 
         [0051]    Preferably, the valve in the fitting permits the flow of fluid from the pump to the potable water heat exchanger but blocks the flow of fluid from the potable water heat exchanger to the pump. 
         [0052]    Ideally, the valve is a Schrader type valve. Alternatively, the valve is a motorized valve. 
         [0053]    Preferably, a length of tubing connects the pump to the connector. 
         [0054]    Preferably, the pump is permanently connectable to the potable water heat exchanger. 
         [0055]    Preferably, in this integrated embodiment, a wiring loom is used to couple switch means to the pump. In this embodiment, the pump switch means can be located with various other switches on a centrally located electrical control panel. 
         [0056]    Accordingly, the present invention provides a method of urging a turbulent fluid flow through a potable water heat exchanger, the method comprising pumping a volume of uncontaminated pressurized air or gas through water inside the potable water heat exchanger for creating a turbulent flow of water and gas through the potable water heat exchanger for removing contaminants from the inside surface of the potable water heat exchanger. 
         [0057]    Ideally, the method comprising pumping using a mains electricity or battery operated pump. 
         [0058]    Preferably, the method comprising opening a faucet/tap or other suitable plumbing fitting connected downstream of the potable water heat exchanger. The sudden pulsing of the air or gas which has been pumped through the water in the potable water heat exchanger causes any water which is located inside the potable water heat exchanger to surge through the potable water heat exchanger in a turbulent manner. Some of the water and fluid will exit from the open faucet/tap or other fitting. This turbulent flow effect around and through the components of the potable water heat exchanger dislodges any discrepancies which have deposited on the potable water heat exchanger and these are flushed out of the system through the natural course of events. 
         [0059]    Embodiments of the present invention will now be described in detail with reference to the accompanying figures in which: 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0060]      FIG. 1  is a schematic drawing of a combination boiler having a central heating water heat exchanger and a potable water heat exchanger; 
           [0061]      FIG. 1A  shows a diagram of an apparatus for urging water through a potable water heat exchanger according to a first embodiment of the present invention. 
           [0062]      FIG. 2A  shows a diagram of a second connector of an apparatus for urging water through a potable water heat exchanger according to an embodiment of the present invention and an adapter of the potable water heat exchanger. 
           [0063]      FIG. 2B  shows a diagram of a second connector of an apparatus for urging water through a potable water heat exchanger according to an embodiment of the present invention mated with an adapter of the potable water heat exchanger. 
           [0064]      FIG. 3  shows a diagram of an apparatus for urging water through a potable water heat exchanger according to a second embodiment of the present invention. 
           [0065]      FIG. 4  shows a diagram of an apparatus for urging water through a potable water heat exchanger according to an embodiment of the present invention wherein the apparatus is connected to a tap/faucet of the potable water heat exchanger. 
           [0066]      FIG. 5  shows a diagram of an apparatus for urging water through a potable water heat exchanger according to the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0067]    Referring to the drawings and initially to  FIG. 1 , there is a shown a schematic drawing of a combination boiler indicated generally by the reference numeral  1 . The boiler  1  has a primary heat exchanger  2  which is heated by burner  3 . This heat exchanger  2  heats the mains water fed into the central heating system  4  via feeding loop  8 . The fumes from the burner  3  are exhausted through exit flue  5 . The heated water is pumped via pump  9  to radiators  10  via the central heating system  4 . A diverter valve  14  diverts hot water from the primary heat exchanger  2  to secondary potable water heat exchanger  15  when a sensor detects that a call for domestic hot water has been received at a shower or tap  16 . The hot water from the primary heat exchanger  2  heats the mains cold water feed  18  through the potable water heat exchanger  15  which flows to the shower or tap  16 . Cold mains water inlet  22  flows from the inlet to cold water outlet tap  17 . The secondary potable water heat exchanger  15  has a fitting  19  for engaging a connector or adapter for connecting the apparatus of the present invention thereto. 
         [0068]      FIG. 1A  shows a diagram of an apparatus  100  for urging water through the potable water heat exchanger  15  see  FIG. 1  according to an embodiment of the present invention.  FIG. 2A  and  FIG. 2B  show detailed views of a second connector  161  of the apparatus of  FIG. 1A  for urging water through the potable water heat exchanger  15  and of an adapter  121  which connects to the potable water heat exchanger  15 . For clarity, the same reference numerals are used to describe identical features of  FIG. 1A ,  FIG. 2A  and  FIG. 2B . 
         [0069]    The apparatus of  FIG. 1A  comprises a length of conduit  110  comprising a first connector  151  fixed at a first end  111  of the conduit and a second connector  161  fixed at a second end  112  of the conduit. 
         [0070]    The first connector  151  comprises a flange  152  or gripping area such as ribs (not shown) accommodating a valve  155  of the type typically used on automobile tyres and commonly referred to as a Schrader valve. Valve  155  has a threaded outer diameter, for connection with an outlet of pump  130 , and allows air or gas to flow in a direction from the first end  111  of the conduit to the second end  112  of the conduit  110 . 
         [0071]    The second connector  161  is mateable with an adapter  121  which is attached to a fitting  19  of the potable water heat exchanger  15 . 
         [0072]    The second connector  161  comprises an outer body  162  providing mechanical support for a second connector valve  165 . Second connector valve  165  opens when the second connector  161  is connected to the adapter  121 ; similarly, second connector valve  165  closes when the second connector  161  is disconnected from the adapter  121 . 
         [0073]    In use, a mains water supply shut-off valve (not shown) for potable water heat exchanger  15  is closed, so that water can no longer enter the system from the external supply or well. A pump  130  is connected to first connector  151  so that air or gas can be pumped into the conduit  110  at its first end  111 . The first connector valve  155  prevents the air or gas from escaping back through connector  151  if the pump  130  is disconnected. 
         [0074]    When second connector  161  is connected to adapter  121 , second connector valve  165  opens, so that air or gas which is pumped into first connector  151  via pump  130  passes through conduit  110  and on to potable water heat exchanger  15 . In this way, a volume of pressurized air or gas is pulsed through the water in the potable water heat exchanger  15 . This pressure may be released by opening a faucet/tap  16  or other suitable plumbing fitting to gain entry to the water system downstream of the apparatus  100 . The sudden pulsing of the air or gas which has been pumped through the water in the potable water heat exchanger  15  causes any water which is located inside the potable water heat exchanger  15  to surge through the potable water heat exchanger  15 . Some of the water will exit from the open faucet/tap  16  or other fitting. This turbulent flow effect of water and gas around and through the components of the potable water heat exchanger  15  dislodges any discrepancies which have deposited on the potable water heat exchanger  15  and these are flushed out of the system through the natural course of events. Significant testing has shown that significant discrepancies exist on the components of the potable water heat exchanger  15  and this pulsing effect cleans these discrepancies off the heat exchanger  15  to a significant degree. 
         [0075]    If the plumbing installation comprises several branches (not shown) each having a corresponding faucet or tap, the trapped water containing contaminants can be purged from all of the branches by a sequential process as follows: pumping air or gas into the potable water heat exchanger  15 ; opening a faucet/tap or other fitting attached to one particular branch and allowing the water to be purged from the corresponding branch; closing off that tap; repeating the process of building air pressure for a different branch of the installation having a different faucet/tap or other fitting until all of the branches have been purged. A particular sequence of purging the respective branches of the plumbing installation may provide the most expeditious route to removing all of the water from the system. Alternatively, each branch may be flushed for a period of time once the mains water supply  18  is reconnected to the potable water heat exchanger  15 . 
         [0076]    The potable water heat exchanger adapter  121  is chosen for quick attachment of the apparatus  100  of the present invention so that water can be urged through the potable water heat exchanger  15 . Adapter  121  comprises a threaded portion  122  for attachment to a threaded fitting  19  of the potable water heat exchanger  15 . Such fittings may include (but are not limited to) threaded plumbing fittings having a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. Alternatively, adapter  121  may comprise a flange having a push fit for connection to fitting  19  of the potable water heat exchanger  15  or may comprise a portion facilitating twist lock connection with fitting  19  of the potable water heat exchanger  15 . Further alternatively, the adapter is mateable with a faucet or tap of the fitting  19  of the potable water heat exchanger  15 . 
         [0077]      FIG. 2A  shows a diagram of the second connector  161  of the apparatus  110  for urging water through potable water heat exchanger  15  according to the embodiment of the present invention depicted in  FIG. 1 , where the second connector is aligned to be mated with an adapter  121  of the potable water heat exchanger  15 . 
         [0078]      FIG. 2B  shows a diagram of the second connector  161  of an apparatus  110  for urging water through a potable water heat exchanger according to the embodiment depicted in  FIG. 1 , where the second connector is mated with an adapter  121  of the potable water heat exchanger. 
         [0079]    Second connector  161  comprises a stop valve  165  and has an outer body  162 , which provides mechanical support for valve  165  and other parts of the inner mechanism of second connector  161 . Second connector  161  is formed to have a substantially cylindrical or concave inner orifice  164  to accommodate a protruding portion  124  of the adapter  121  of the potable water heat exchanger  15 . Second connector  161  further comprises releasable lugs  168  for engaging with one or more indentations around the circumference of adapter  121  of the fitting  19  of the potable water heat exchanger  15 . Second connector  161  may optionally further comprise a washer formed of a flexible material such as rubber or soft plastic to provide an air tight and water tight fit between the second connector  161  of the apparatus and adapter  121 . 
         [0080]    Second connector  161  is directional, and has an input side  160 A and an output side  160 B. Stop valve  165  has a cover  166  which closes against a build up of pressure on its input side  160 A. In this state, second connector  161  is closed against a flow of fluid or gas from its input side  160 A to its output side  160 B—see  FIG. 2A . 
         [0081]    Adapter  121  comprises a threaded portion  122  for mating with the fitting  19  of the potable water heat exchanger  15  and further comprises a protruding portion  124  for mating with second connector  161  of the apparatus of the present invention. When mated together, the protruding portion  124  of adapter  121  engages a portion of cover  166  of second connector  161  thereby causing second connector to switch to its open state—as shown in  FIG. 2B . 
         [0082]    In the embodiments of the present invention shown in  FIG. 1 ,  FIG. 2A ,  FIG. 2B  and  FIG. 3 , adapter  121  comprises a threaded portion  122  for directly engaging with a threaded fitting  19  of the potable water heat exchanger  15 . The threaded portion of plumbing may provide an inverse fit for a female plumbing fitting having a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. Nonetheless, the present invention is not limited to any specific adapter and may include variants to connect the apparatus  110  to a wide range of plumbing fittings. 
         [0083]      FIG. 3  shows a diagram of an apparatus for urging water through a potable water heat exchanger  15  according to a second embodiment of the present invention. 
         [0084]    The apparatus of  FIG. 3  comprises a length of conduit  310  comprising a first connector  351  fixed at a first end  311  of the conduit and a second connector  361  fixed at a second end  312  of the conduit. Conduit  310  further comprises a reservoir tank  315  located between its first end  311  and its second end  312 . A manometer  316  is also connected to conduit  316 , for measuring the pressure of the air or gas inside conduit  310  and reservoir tank  315 . 
         [0085]    The first connector  351  comprises a flange  352  or domed end (not shown) having a valve such as an automobile tyre valve  355  fitted. Valve  355  allows air or gas to flow in a direction from the first end  311  of the conduit  310  to the second end  312  of the conduit  310 . 
         [0086]    In use, an outlet of automobile tyre pump  130  or any compressor, most preferably a digital compressor with an auto shut off function, is connected to first connector  351  so that air or gas can be pumped into the conduit  310  at its first end  311 . Air or gas pressure builds up inside conduit  310  and reservoir tank  315  over a period of time so that the trapped air or gas has a corresponding unpressurised volume which is greater than that of the combined inner volume of conduit  310  and reservoir tank  315 . Ideally, the corresponding unpressurised volume of gas is several times that of the combined inner volume of conduit  310  and reservoir tank  315 . Specifically, after pressurization, the corresponding unpressurised volume of gas may be up to twenty times that of the combined inner volume of conduit  310  and reservoir tank  315 , corresponding to pressure of approximately twenty atmospheres. Manometer  316  provides a measure of the pressure of the air or gas inside reservoir tank  315  and conduit  310 . Manometer  316  provides a safety means against the over inflation of reservoir tank  315 . 
         [0087]    Conduit  310  may further comprise a pressure release valve (not shown). For example, a pressure release valve may be included so that the pressure inside the reservoir tank  315  cannot exceed a particular level. 
         [0088]    Second connector  361  is mateable with an adapter  121  of the fitting  19  of the potable water heat exchanger  15 . Adapter  121  is connected to the fitting  19  of the potable water heat exchanger  15  via a threaded portion  122 . The second connector  361  comprises a second connector valve  365  which has a closed state and an open state. Second connector valve  365  is initially closed allowing the air or gas pressure to build up inside conduit  310  and reservoir tank  315 . Second connector valve  365  opens when the second connector is connected to the potable water heat exchanger adapter  121 . Connection of second connector valve to potable water heat exchanger adapter  121  in this way, causes the trapped air or gas which is inside conduit  310  and reservoir tank  315  to be transferred to the potable water heat exchanger  15 . 
         [0089]    In this way, a volume of pressurized air or gas is pulsed through the water in the potable water heat exchanger  15 . This pressure may be released by opening a faucet/tap  16  or other suitable plumbing fitting to gain entry to the water system downstream of the apparatus  100  of the present invention. The sudden pulsing of the air or gas which has been pumped through the water in the potable water heat exchanger  15  causes any water which is located inside the potable water heat exchanger  15  to surge through the potable water heat exchanger  15 . Some of the water will exit from the open faucet/tap  16  or other fitting. This turbulent flow effect of water and gas around and through the components of the potable water heat exchanger  15  dislodges any discrepancies which have deposited on the potable water heat exchanger  15  and these are flushed out of the system through the natural course of events. 
         [0090]    In use, the pump  130  of the embodiment of the present invention depicted in  FIG. 3  may be remote from the potable water heat exchanger  15 . In this case, conduit  310  and reservoir tank  315  are pressurised remotely, and are then brought to the potable water heat exchanger  15 . 
         [0091]      FIG. 4  shows a diagram of an apparatus for urging water through a potable water heat exchanger  15  according to an embodiment of the present invention wherein the apparatus is connected to a tap or faucet  19  of the potable water heat exchanger  15 . 
         [0092]    The apparatus of  FIG. 4  comprises a length of conduit  110  comprising a first connector  151  fixed at a first end  111  of the conduit and a second connector  161  fixed at a second end  112  of the conduit. 
         [0093]    The first connector  151  comprises a flange  152  accommodating a valve  155  such as the type typically used on automobile tyres and commonly referred to as a Schrader valve. Valve  155  has a threaded outer diameter, for connection with an outlet of a pump  130 , and allows air or gas to flow in a direction from the first end  111  of the conduit to the second end  112  of the conduit. 
         [0094]    The second connector  161  is mateable with an adapter  121  which is attached to a faucet or tap  19  of the potable water heat exchanger  15 . Ideally faucet or tap  19  is located on the potable water heat exchanger  15  at some point near or adjacent to the main shut-off valve. 
         [0095]    The second connector  161  comprises an outer body  162  providing mechanical support for a second connector valve  165 . Second connector valve  165  opens when the second connector  161  is connected to the plumbing faucet or tap  19  via adapter  121 ; similarly, second connector valve  165  closes when the second connector  161  is disconnected from the faucet or tap  19 . 
         [0096]    In use, a water supply shut-off valve (not shown) for potable water heat exchanger  15  is closed, so that water can no longer enter the system from the external supply or well. Faucet or tap  19  is then opened. A pump  130  is connected to first connector  151  so that air or gas can be pumped into the conduit  110  at its first end  111 . The first connector valve  155  prevents the air or gas from escaping back through connector  151  if the pump  130  is disconnected. 
         [0097]    When second connector  161  is connected to faucet or tap  19  via adapter  121 , second connector valve  165  opens, so that air or gas which is pumped into first connector  151  via pump  130  passes through conduit  110  and on to potable water heat exchanger  15 . In this way, a volume of pressurized air or gas pulses through the water in the potable water heat exchanger  15 . The sudden pulsing of the air or gas which has been pumped into the potable water heat exchanger  15  causes any water which is located inside the potable water heat exchanger  15  to surge through the potable water heat exchanger  15 . Some of the water will exit from the open faucet/tap  16  or other fitting. This turbulent flow effect of water and gas around and through the components of the potable water heat exchanger  15  dislodges any discrepancies which have deposited on the potable water heat exchanger  15  and these are flushed out of the system through the natural course of events. 
         [0098]    Thus, the apparatus of the present invention as described herein provides a compact and portable apparatus capable of urging water through the potable water heat exchanger  15 . The apparatus of the present invention can be deployed on a range of existing potable water heat exchanger without there being a need for modification to the installation. 
         [0099]    The apparatus of the present invention  100  as depicted in the first embodiment of  FIG. 1  and the embodiments of  FIG. 3  and  FIG. 4  may alternatively be connected directly to a connector or a faucet or tap of potable water heat exchanger  15 . In this case, adapter  121  is superfluous. 
         [0100]      FIG. 5  shows a diagram of an apparatus  500  for urging a turbulent flow of water and gas through a potable water heat exchanger  15 . The apparatus  500  has a potable water heat exchanger  15  and a fitting  19 , fixably attached in-line with the potable water heat exchanger  15  so that fluid flowing through the potable water heat exchanger  15  passes through the fitting  19 . The fitting  19  is mated to a connector  522  of a pump  530  for urging a turbulent flow of fluid through a potable water heat exchanger  15 . The fitting  19  has a valve similar to the valve  155 ,  165  of  FIGS. 1 to 4  for preventing passage of fluid from the potable water heat exchanger  15  into the connector  522  and on to the pump  530 . Advantageously, an operator can simply connect a pump  530  to the in-built fitting  19 . 
         [0101]    The apparatus  500  has a pump  530  having a connector  522  mated with a portion of the fitting  19 . The pump  530  is located within a dwelling or structure served by the potable water heat exchanger  15 . The pump  530  is operable by a switch  540  or other member of activation located within the dwelling or structure served by the potable water heat exchanger  15 . The switch  540  or other member of activation couples the pump to a power supply. The power supply is a 12V DC or a 240 V AC power supply. The pump  530  is fitted with a pressure sensor  570  to measure the generated pressure of the fluid the pump  530  is pumping. The pump  530  has a limiter switch to switch the pump  530  off or on at a predetermined pressure level. 
         [0102]    The limiter switch has an upper limit of approximately 30 psi. Advantageously, this pressure suits fixed homes and caravans. Alternatively, the limiter switch has an upper pressure limit of approximately 15 psi. Advantageously, this pressure suits towing caravans, motor homes, and boats. The pressure sensor  570  is a mechanical sensor, such as a manometer. Alternatively, the pressure sensor  570  is an electronic sensor. 
         [0103]    The fitting  19  has a connector  522  protruding from the potable water heat exchanger  15 . The connector  522  is a threaded plumbing fitting and has a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. The valve in the fitting  19  permits the flow of fluid from the pump  530  to the potable water heat exchanger  15  but blocks the flow of fluid from the potable water heat exchanger  15  to the pump  530 . The valve is a Schrader type valve. Alternatively, the valve is a motorized valve. In some embodiments, the potable water heat exchanger  15  is installed in one of: a mobile home, an occasional or full time residence, a motor home, a recreational vehicle (RV), a boat/barge. 
         [0104]    A length of tubing  550  connects the pump  530  to the connector  522 . In one embodiment, the pump  530  is permanently connected to the potable water heat exchanger  15 . Alternatively, the tubing  550  and connector  522  are integrally formed with the potable water heat exchanger  15  and the pump  530  is the only equipment a service technician requires to flush the system. The connector  522  is permanently connectable to the fitting  19 . Advantageously, the apparatus  500  can be built into the potable water heat exchanger  15  as an integrated component. 
         [0105]    A wiring loom  580  is used to couple switch member  540  to the pump  530 . 
         [0106]    In this embodiment, the pump switch member  540  is located with various other switches on a centrally located electrical control panel. 
         [0107]    In use, a water supply shut-off valve (not shown) for potable water heat exchanger  15  is closed, so that water can no longer enter the system from the external supply or well. Pump  530  is connected to the fitting  19  through connector  522 , if the pump is not permanently coupled thereto, so that air or gas can be pumped into potable water heat exchanger  15 . The valve in fitting  19  prevents the air, gas, or residual water from escaping back through connector  522  when the pump  530  is deactivated. 
         [0108]    On activation of the pump  530 , a volume of pressurized fluid such as air or gas pulses through the water in the potable water heat exchanger  15 . The sudden pulsing of the air or gas which has been pumped into the potable water heat exchanger  15  causes any water which is located inside the potable water heat exchanger  15  to surge through the potable water heat exchanger  15 . Some of the water will exit from the open faucet/tap  16  or other fitting. This turbulent flow effect of water and gas around and through the components of the potable water heat exchanger  15  dislodges any discrepancies which have deposited on the potable water heat exchanger  15  and these are flushed out of the system through the natural course of events. 
         [0109]    In the embodiment of the present invention shown in  FIG. 5 , the fitting  19  comprises a threaded portion for directly engaging with a threaded fitting of connector  522 . The threaded portion of the plumbing may provide an inverse fit for a female plumbing fitting having a diameter equal to one of: ½ inch, ¾ inch, 1 inch or any fitting up to 12 inches and beyond. Nonetheless, the present invention is not limited to any specific adapter and may include variants to connect the apparatus  500  to a wide range of plumbing fittings. 
         [0110]    Thus, the present invention as described herein provides a compact and possibly integrated apparatus capable of removing contaminants from potable water heat exchangers  15 . 
         [0111]    In relation to the detailed description of the different embodiments of the invention, it will be understood that one or more technical features of one embodiment can be used in combination with one or more technical features of any other embodiment where the transferred use of the one or more technical features would be immediately apparent to a person of ordinary skill in the art to carry out a similar function in a similar way on the other embodiment. 
         [0112]    In the preceding discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of the said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value. 
         [0113]    The features disclosed in the foregoing description or the following drawings, expressed in their specific forms or in terms of a means for performing a disclosed function, or a method or a process of attaining the disclosed result, as appropriate, may separately, or in any combination of such features be utilised for realising the invention in diverse forms thereof as defined in the appended claims.