Abstract:
A continuous-flow water distiller includes a housing having a removable heating vessel which receives water to be distilled A heater is immersed within the water in the vessel for producing steam. The housing includes an openable lid which, when closed, seals the heating vessel so that steam can be directed through an outlet into a condenser located in the housing. Raw water is supplied to the heating vessel through a heat exchanger to preheat the raw water by effectively utilizing thermal energy recovery to initiate cooling of the steam, and distillate is supplied through the condenser to enhance heat exchange.

Description:
This application is a continuation-in-part of U.S. application Ser. No. 08/649,013, filed May 16, 1996, now U.S. Pat. No. 5,932,073, which issued on Aug. 3, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates, in general, to a distillation device for purification of water, and more particularly to a compact, continuous flow distiller for supplying pure drinking water. 
     The global need for safe drinking water is commonly recognized. Increasing awareness of health problems resulting from chemicals, bacteria and viruses in drinking water is well documented. Point of use water purification by distillation is the best and only solution that addresses all water contamination problems. 
     Many water distillers have been developed to provide pure drinking water, however certain problems still exist in the art. Examples of some of these problems are: (1) some distillers are not economical since they have unnecessary maintenance cost and a low energy efficiency; (2) some produce too much heat radiating into the air, particularly in small offices and enclosed work area; (3) most water distillers are noisy because they have electric cooling fans that run at inconvenient times; (4) some water distillers have attempted to overcome the noise problem by using water cooled condensers; however, in the prior art this has created wastewater and required additional plumbing; and (5) some water distillers are difficult to maintain in good operating condition because of the difficulties encountered in cleaning sediment and scale from the interior of the distiller. In fact most water distillers require a substantial amount of disassembly involving multiple parts in order to fully clean the boiler. In many cases, the user will not realize the difficulty of this job until the water distiller fails to produce water up to its rated capacity. 
     Numerous attempts have been made to facilitate the de-scaling and cleaning of distillers, but such attempts have not completely solved the problems in the prior art. In most cases, such attempts have resulted only in additional plumbing and additional components, requiring additional maintenance and increasing the cost of the unit. Thus, the cost and maintenance of these prior art devices is an acknowledged disadvantage. 
     To avoid the need to disassemble a distiller, many attempts have been made to address the cleaning problem by the use of after market chemicals for removing scale in the boiler. However, this has not eliminated the difficult periodic required manual cleaning for proper maintenance of distiller components. Further, the use of chemicals for this purpose is expensive, a waste of natural resources and ultimately adds to the already-serious pollution problems. 
     SUMMARY OF THE INVENTION 
     It is a primary object of the present invention to address environmental and public health concerns regarding the provision of safe drinking water in an effective manner. 
     It is a further object of the invention to provide a water distiller that is more economical and energy efficient; for example; by effectively utilizing thermal energy recovery to preheat water to be treated; by operating during lower electrical rate periods; and by eliminating wastewater. 
     It is another object of the invention to reduce heat radiation into the surrounding air space, particularly during normal office and working hours by operating primarily during off work hours and/or by evacuating heat to a remote location. 
     It is another object of the invention to provide a water distiller which is so constructed as to protect the condenser from being negatively affected by radiant heat from the boiler or from the boiler heat source by positioning the condenser below the boiler and heat source. 
     It is another object of the invention to provide a water distiller that reduces noise, particularly during normal office and working hours, by eliminating a condenser fan and/or by operating during off work hours. 
     Yet another object of the invention is to provide a water distiller that may use cooling water to enhance heat exchange without creating wastewater, without requiring plumbing and connections to a house or building drain system, and without fouling cooling water tubing by utilizing distilled water from the reservoir for this purpose. 
     A still further object of the invention is to eliminate the difficulties and the cost encountered in cleaning sediment and scale from the interior of a boiler in a distiller by providing a removable boiler [in a distiller], which is seated within the housing in such a way that it can be easily removed for cleaning or replacement. 
     Another object of the invention is to provide a water distiller with a protective control to prevent the boiler from running dry, thus preventing scale. 
     Briefly, the present invention is directed, in its preferred embodiments, to a water distillation system which effectively addresses known problems in the art. The embodiments are directed to a continuous-flow distiller for permanent placement as a freestanding unit in any desired location. Such a device provides a continuous supply of pure water and may, for example, serve as a drinking fountain. The distiller includes a removable heating vessel, or boiler, which receives water that is to be treated, and a heater. The water in the boiler is boiled by the heater and the resulting steam or vapor is directed into, and through, a condenser which provides heat exchange surfaces to allow the steam to give off its heat through the condenser walls, thereby causing the steam to return to its water form. The lowermost end of the condenser includes a drain opening which directs the distilled water into a reservoir, or storage container. The storage container may be a stationary container for use, for example, in a water fountain and a pump may be provided to deliver water from this container. 
     In a preferred embodiment, the components are located within a housing having a hinged access lid at the top. The boiler is supported in the housing, as by suitable angle brackets or other supports, and may be in the form of an insulated double wall pot of stainless steel. The boiler may have a recessed area in its bottom with a drain tube and a drain spigot connected to a drain hole therein, extending downwardly and outwardly through a side hole in the housing. The open top of this boiler is closed and sealed by the housing lid, with an outlet steam port in the lid being connected to the inlet of a condenser. Preferably, the steam port is connected by way of a suitable pipeline, which passes through a raw water pre-heating chamber on its way to the inlet of the condenser. The raw water pre-heating chamber has an inlet and an outlet. Water to be distilled is supplied by way of a raw water inlet pipe to the pre-heating chamber inlet and preheated raw water is supplied from the chamber outlet to the boiler by way of a supply pipe passing through the hinged lid. 
     The outlet steam port and pipeline leads steam from the boiler to the inlet of the condenser, which in accordance with the present invention is located below the boiler and below the boiler heat source. The condenser, in a preferred embodiment, is water and air-cooled and includes a downwardly coiled, double-wall tubing or a smaller tube within a larger tube. Cooling water flows through the inner tube, while steam enters the larger outer tube at a steam inlet and flows downwardly as it condenses. The resulting distillate flows downwardly by gravity to a distillate outlet drain. 
     An enclosed container or storage vessel is located below the condenser and receives water from the distillate drain for storage and subsequent distribution through a suitable outlet such as a distillate spigot which may be located at any desired position on the housing. If the spigot is located above the storage container, a pump may be provided to deliver water to it. 
     The smaller, cooling-water, inner tubing of the condenser extends downwardly, through the distillate drain at the lower end of the condenser, and is connected to an outlet of a cooling-water pump located, if so desired, at the bottom of the storage container. At the upper end of the condenser the cooling-water tubing exits the condenser through a hole in the outer steam tubing and extends downwardly through a hole in the top of the storage container and terminates at a cooling-water exit within the storage container. 
     The heating unit for the boiler preferably is a horizontal heating element connected to the lower end of a vertical heating unit stem, or support, that is connected to, and extends downwardly from, the lid. 
     A second embodiment of the invention is essentially the same as the first embodiment; however, in this case the condenser is of the heat exchange chamber or plate(s) type having cooling water circulated within and through the chamber or plate configuration, as is known in the industry. In any event, a cooling fan may be used, if desired, to enhance the flow of ambient air on the outside surfaces of the condenser. 
     A third embodiment is similar to the first and second embodiments, the difference being that the condenser is a typical coiled finned tubing type with a cooling fan and a shroud. Also the cooling-water pump and associated tubing have been eliminated. 
     A fourth embodiment is similar to the third embodiment, the difference being the addition of an exhaust pipe and hose to exhaust radiant heat from the condenser to a remote location such as outside a house or building. 
     Although four embodiments are illustrated, it will be understood that the specific shape and dimensions of the distiller can be varied to adapt it to a wide range of applications in various industries and at any desired location. It will become clear in the following description that the device provides a continuous flow water distiller with unique improvements and advantages over prior art including: (a) a significant increase in energy efficiency; (b) a significant reduction of heat in the surrounding air space; (c) significant reduction of noise; (d) the elimination of wastewater; and (e) the device is also unique in that it can be easily cleaned by simply lifting the lid of the housing and lifting the boiler out for cleaning purposes. This also facilitates replacement of the boiler if necessary, and provides ready access to the heater unit for adjustment or repair. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing, and additional objects, features and advantages of the present invention will be more fully understood by reference to the following detailed description of preferred embodiments thereof, taken in conjunction with the accompanying drawings, in which: 
     FIG. 1 is a cross sectional view of a preferred embodiment of the present invention, illustrating the components of a continuous mode distiller including a water and air-cooled, double tubing condenser; 
     FIG. 2 is a side elevation view of the distiller of FIG. 1 illustrating a plurality of air vents. 
     FIG. 3 is a cross sectional view of a second embodiment of the present invention, illustrating a continuous mode distiller including a water and air-cooled chamber or plate type condenser; 
     FIG. 4 is a partial cross sectional layout view of a third embodiment of the present invention, illustrating the continuous mode distiller including a typical coiled finned tubing (fins not shown) condenser and a cooling fan; and 
     FIG. 5 is a partial cross sectional layout view of a fourth embodiment of the present invention, illustrating the continuous mode distiller of FIG. 4 with the addition of a remote exhaust system. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Turning now to a more detailed consideration of the present invention, there is illustrated in FIG. 1 a continuous mode water distiller generally indicated at  10 . The distiller includes a housing  12  which may be generally cylindrical, if desired, and which is preferably constructed of metal or a durable plastic material. The housing  12  is supported by a stand  14  and is closed at its bottom by a bottom wall  16  and at its top by a hinged lid  18 . The lid  18  preferably is secured to the top edge of housing  12  by one or more hinges  20  and may be opened by pivoting it upwardly and to the left, as viewed in FIG. 1, to provide access to the interior components of the distiller  10 . 
     The distiller  10  incorporates a removable double-wall boiler pot or vessel  22  that is supported within the housing  12  by suitable brackets  24 , for example. These brackets  24  are secured to the interior of the housing  12  and provide a seat for receiving boiler  22  and holding it securely in place within the housing. The boiler  22  incorporates, for example, cylindrical, dual, spaced side walls  26  and flat, circular, dual, spaced bottom walls  28  providing a thermally insulative air space  30  between the dual walls and dual bottom. The boiler  22  is for receiving water  32  which is to be distilled. If desired, the boiler  22  may further incorporate a drain line  34  connected to a drain outlet  36  in a recessed area  38  in its bottom wall  28 . A drain spigot  40  at the end of the drain line  34  may protrude through a drain opening  42  in the housing  12  for draining the water  32  from the boiler  22 . The brackets  24  are so located as to position the boiler  22  with its open top edge engageable by a seal on the interior of lid  18  so that when the lid is closed, the boiler  22  is closed and sealed to prevent the escape of steam during the distillation process. 
     Raw water to be boiled is supplied to the boiler  22  by way of a feed line  44  which is connected to a pre-heating chamber  46  at a pre-heating inlet  48 . The raw water passes through a heat exchange passageway in the pre-heating chamber  46 , then through a connector line  50  connected to a pre-heating chamber outlet  52 . Connector line  50  extends through lid  18  and terminates above the interior of the boiler  22  at a nozzle  54 . Feed line  44  is connected by way of a quick connect junction  56  to a water supply line  58  with the water flow being regulated by a valve  60 . The level of water in boiler  22  is regulated by a controller  62  operated by a float  64 , the float serving to sense the water level, and the controller  62  serving to regulate the flow of water into the boiler  22  by way of a conventional valve at nozzle  54 . 
     A heat source  70  is disposed within the boiler  22  and is connected to the bottom of a support such as a vertical stem  72 , which in turn is mounted on and extends downwardly from the inside of the lid  18 . The stem  72  and the heater  70  move with the lid, and the heater is submerged in water  32  when the lid  18  is closed. The heater  70  is connected by way of an electrical cord  74  through control box  76  and cord  78  to a suitable source of power (not shown). The control box  76  may be connected to an on-off control switch  80 , and may include a thermostat, circuit breakers, and related controls for the heater. 
     Included in lid  18  is an outlet steam port  86  which has an inlet end  88  which is positioned above the boiler  22  when the lid  18  is closed for conveying steam from the boiler  22  through a steam tube  90  which passes through the pre-heating chamber  46  in route to the inlet end  92  of a condenser  94 . The heat from the steam in tube  90  preheats the raw water being supplied to the boiler from chamber  46  through connector line  50 . 
     The condenser  94 , in the illustrated preferred embodiment of FIG. 1, includes a downwardly coiled double tubing comprising an outer tube  96  to provide a passageway for steam to condense into distillate and an inner tube  98  to provide a passageway for cooling water to travel in the opposite direction of the steam. A distillate drain terminal  100  at the lower end of the outer tubing  96  directs distilled water into a storage container  102  supported within the housing  12 . The container  102  receives and stores distilled water  104  from condenser  94  and is supported within housing  12  by a suitable base  106  The water storage container  102  may be of a suitable plastic material and incorporates a level control float  108  connected to a heater control switch  110  for switching the heater  70  on and off in response to the water level in the container  102 . Switch  110  is connected in series in power line  74  for this purpose, and enables the heater  70  to automatically switch on when the water level in the storage container  102  falls below a set level. 
     The distillate drain terminal  100  is spaced slightly above an inlet  114  in the top wall  116  of storage container  102 , the spacing between drain  100  and inlet  114  serving as a gas vent  118  for the system to provide equalization of pressure in the condenser  94  and in the storage container  102 . If desired, an air filter  119  may be provided around the vent  118  to prevent entry of contaminates into the container  102 . 
     A cooling water pump  130  located, for example, in a suitable housing mounted on the bottom wall  132  of the storage container  102  is provided to deliver cooling water from the storage container upwardly through a cooling water delivery line  134 . The pump  130  supplies water to the lower end of the inner tubing  98  of the condenser  94  wherein it is conveyed through the condenser in the opposite direction of the flow of steam, thus providing excellent heat exchange within condenser  94 . A cooling water return line  136  connected to an inner tube exit port  138 , located near the inlet end  92  of the outer tubing  96 , extends downwardly through a return port  140  in the top wall  116  of container  102  to a cooling-water terminal  142  within container  102  to provide a return passageway for the cooling water. If desired, an external water source may be used for cooling, but the use of distilled water from container  102  is preferred, since this water is clean and will not foul the cooling tube. 
     A timer control  144  may, if desired, be in line with cord  74  to provide power to the heat source  70  (and cooling water pump  130  of FIGS. 1 &amp; 3) only during predetermined time periods; for example, between six PM and six AM, to provide a distiller that eliminates noise and radiant heat from the distiller in an office or work place during normal working hours. This also provides a distiller that operates in off peak power demand periods, thus taking advantage of cheaper electric rates and may negate a need for an upgrade in wiring or power source capacity. This also provides a distiller that assures substantial replacement of water in its storage container  102  thus preventing the stored water from becoming stale or stagnant. 
     If desired, a low water sensor  150  may be located, for example, on a side wall  152  of the storage container  102  to sense an extreme low water level in container  102 , and may be connected to the controller  76  to provide power to the heater  70  (and pump  130  of FIGS. 1 &amp; 3) to bypass the timer control  144  to provide distiller operation during times when extra production is required. 
     Water in the storage container  102  is delivered to a suitable outlet spigot  151  which may be connected by way of water line  153  to a pump  154  located, for example, in a suitable housing mounted on the side wall  152  of the container  102 . It will be understood that in the alternative, the pump  154  can be mounted on the top wall  116  of the container  102  or, if desired, the spigot  151  can be mounted directly into the side wall  152  of the container  102  near the bottom thereof In the event an air cooled condenser is used, as will be described with respect to FIGS. 4 and 5, pump  154  may, if desired, be mounted on the bottom wall  130  of container  102 . 
     In yet another alternative, the distiller  10  may provide water to a remote delivery system, indicated in phantom at  160  (FIG.  1 ), wherein pump  154  may be connected by suitable pipeline(s), indicated by dotted line(s)  162 , to one or more remote spigots  164 , which may be located at remote location(s) such as on counter top(s), in office(s), and/or in hallway(s). 
     If desired, a water cooling system  170  may be disposed within the base  106  below the storage container  102  for cooling the water  104  in the storage container  102 , in known manner. 
     Also, if desired, a filler  172  with a filler cap  174  may be located just below lid  18  between the boiler  22  and the housing  12 . The filler may be connected to a nipple  176 , which may be screwed through a hole in the top wall  116  of storage container  102 , by way of a filler line  178  to provide a passageway for initially introducing a small amount of distilled water into storage container  102  for providing start up water for the cooling water pump  130  (FIGS.  1  &amp;  3 ). 
     As best illustrated in FIG. 2, a number of air inlet and outlet vents  190  are provided in the housing  12  to permit a free flow of air through the water cooling system  170  and through the condenser  94 , with air entering the vents below the condenser  94  and passing upwardly through the condenser before exhausting through exit vents located above the condenser. 
     FIG. 3 illustrates the distiller  10  of FIG. 1 having a water and air-cooled chamber or plate(s) type condenser  200  instead of the double tubing condenser  94 . The primary difference is that the chamber or plate(s)  202  replaces the outer tubing  96  of FIG.  1 . 
     FIG. 4 illustrates the distiller  10  of FIG. 1 having a typical air-cooled, condenser  204  including coiled, finned tubing  206 , a fan  208  and a shroud  210  replacing the water and air-cooled condenser  94  and the cooling water pump  130  system of FIG.  1 . As seen in FIG. 4 the fan  208  may be mounted on the top wall  116  of the storage container  102  below the coiled finned tubing  206 . For clarity, the fins on the tubes are not shown. The shroud  210 , preferably comprising a suitable light weight plastic material, is connected to the interior of the housing  12  above the inlet air vents  190  (FIG. 2) and is open at its top to direct air flow through finned tubing  206 . 
     FIG. 5 illustrates the distiller  10  of FIG. 4 with the addition of a remote exhaust system  214  including an exhaust pipe  216 , which may comprise a light weight plastic pipe, connected to the open upper end of the shroud  210  and protruding through the side of the housing  12 . A vent hose  218 , which may comprise a light weight flexible hose similar to a dryer vent hose used for a typical clothes dryer, is connected to the protruding end of the exhaust pipe  216  and provides a passageway for conveying hot air from the fine tubing  206  to a remote location such as outside of a house or building. 
     In operation, the present invention is a fully automatic water distiller. The water distiller  10  illustrated in FIG. 1 is a simple device which is installed simply by connecting raw water feed line  58  to inlet line  44  of the device by means of quick connect fastener  56  and by opening valve  60  on the raw water line  58 . (For the water and air-cooled condenser  94  of FIG. 1, and the condenser  200  of FIG. 3, a small amount of distilled water is poured into the storage container  102  through filler  172  to provide start up water for the cooling water pump  130 ). The distiller  10  is then turned on to provide electric power from the circuit control box  76  to the heater  70  (and to the cooling water pump  130 , of FIGS. 1 &amp; 3) as raw water to be distilled flows into the boiler  22 . When the water  32  in boiler  22  reached a desired level, automatic controller  62  turns off the water supply. The heat source  70  then boils the water  32  in boiler  22  and the resulting steam is directed through exit port  88  and through the steam tube  90 , which passes through pre-heating chamber  46 , to condenser  94 , where the steam condenses into distilled water. This distilled water flows by gravity into storage container  102 . Raw water from inlet line  44  passes through the pre-heating chamber  46 , where it is pre-heated by steam tube  90  prior to entering the boiler  22  through connector line  50 . 
     When the distilled water reaches a predetermined level in storage container  102 , level control float  108  operates heater control switch  110  to break the circuit to the heater  70  (and cooling water pump  130  of FIGS.  1  &amp;  3 ). When the distilled water level in container  102  is reduced to a predetermined level, the float  108  signals the control switch  110  to close the circuit to the heater  70  (and pump  130  of FIGS. 1 &amp; 3) to thereby resume boiling water in boiler  22  to produce additional distilled water. This cycle is fully automatic, with the two float switches maintaining the desired water level in the boiler  22  and in the storage container  102 . The compressor  170  cools the distilled water in the storage container  102  to a desired temperature and pump  154  delivers water on demand from container  102  to spigot  151  and or to remote spigot(s)  164 . 
     The lid  18  on the boiler  22  is connected to the housing  12  by suitable hinge(s)  20 , so that the housing  12  can be opened for ready access to the boiler  22  and other interior components such as the heater  70 . The boiler  22  can be simply lifted out of the housing  12  to permit easy cleaning and maintenance. The simple and easy removal of the boiler  22  is possible because the boiler  22  is independently seated on support brackets  24  rather than being mounted to the side wall of the housing  12 . Thus the boiler  22  is a totally separate and independent part. The need for cleaning the boiler  22  is minimized because the level of the raw water  32  is automatically maintained, thereby eliminating the build up of baked-on scale and chemical deposits. The boiler  22  may also have a drain  34 , if desired, to periodically drain the water  32  from the boiler  22  to flush out the impurities left suspended in the water  32  during the operation of the distiller  10 . 
     The timer control  144  may provide power to the heater  70  (and cooling water pump  130  of FIGS. 1 &amp; 3) only during predetermined time periods; for example, between six PM and six AM, to limit the normal distillation operation to a time when an office or work place is not occupied, thus eliminating noise and radiant heat during normal working hours. This also substantially increases the energy efficiency of the distiller  10  because: (a) the heater  70  (and pump  130  of FIGS. 1 &amp; 3) are not continuously going on and off in response to the heater control switch  110 ; (b) the water  32  in the boiler  22  does not have to be continuously re-heated and the incoming raw water is always preheated in the preheating chamber  46  by steam tube  90 ; and (c) the heater  70  (and cooling water pump  130  of FIGS. 1 &amp; 3) only operate during off peak power demand periods, thus taking advantage of cheaper electric rates and may negate a need for an upgrade in wiring or power source. Also by allowing the level of the water  104  in storage container  102  to go down substantially during day time consumption and completely refilling it at night prevents the stored water in container  102  from becoming stale or stagnant. 
     The low water sensor  150  senses an extremely low water level in container  102 , and allows power to the heater  70  (and pump  130  of FIGS. 1 &amp; 3) to bypass the timer control  144 , thus providing operation during times when extra production of pure water is required. 
     The above describes the operation of the four illustrated embodiments of the invention except for their differences in condensing systems and condenser cooling systems. The following describes these differences. 
     As illustrated in FIG. 1, the distiller  10  includes a water and air-cooled, downwardly coiled, double tubing condenser generally indicated at  94  and the cooling water pump  130 . In operation, power is provided to pump  130  and to the heater  70  (and if desired, to a condenser cooling fan which is not shown in FIGS. 1 &amp; 3) at the same time. Steam from the boiler  22  enters the upper end of outer tubing  96  of condenser  94  at inlet  92  and travels downwardly therein toward distillate drain terminal  100  at the lower end of outer tubing  96 . At the same time, cooling water pump  130  in storage container  102  delivers cooling water upwardly through cooling water delivery line  134  to the lower end of the inner tubing  98  wherein it is conveyed in the opposite direction of the steam in the outer tubing  96  thus providing excellent heat exchange within condenser  94 . The cooling water exits the inner tubing  98  at exit port  138 , located near the inlet end  92  of the outer tubing  96 , and flows downwardly through return line  136  to cooling water terminal  142  within container  102 , providing a return passageway for the cooling water. During this condensing process the steam in outer tubing  96  gives off its heat to the ambient air and to the cooling water in inner tubing  98 . The resulting distilled water within the outer tubing  96  and outside of the inner tubing  98  flows by gravity into the storage container  102 . If desired, a fan may be used to enhance air movement (for example, as illustrated in FIGS.  4  &amp;  5 ). 
     The second embodiment (FIG. 3) of the invention operates in the same way as the first embodiment (FIG.  1 ), the difference being that the condenser  200  is of the chamber or plate(s) type instead of the outer and inner tubing type of the first embodiment (FIG.  1 ). 
     The third embodiment (FIG. 4) of the invention operates substantially the same as the first and second embodiments (FIGS.  1  &amp;  3 ), the difference being that the condenser  204  is only air-cooled. Steam from the boiler  22  is conveyed downwardly through the typical finned tubing  206 . Fan  208  forces cooling-air through shroud  210  to enhance heat exchange for the finned tubing  206  during the condensing process of the steam and the resulting distilled water flows by gravity into the storage container  102 . 
     The fourth embodiment (FIG. 5) of the invention is the same as the third embodiment (FIG.  4 ), with the addition of remote exhaust system  214 . The fan  208  forces cooling-air through shroud  210  to enhance heat exchange for the finned tubing  206 . During the heat exchange operation the cooling-air becomes warm. This warm air is conveyed through exhaust pipe  216  and vent hose  218  to a remote location such as outside of a house or building. 
     Thus, it will be seen that the water distiller of the present invention is unique and provides numerous improvements and advantages over the prior art. The distiller is well suited for use in a wide variety of locations, including dentist offices, hospitals, homes, schools, restaurants, cafeterias, business offices, and the like, as may be desired. 
     Although the invention has been described in terms of preferred embodiments, it will be understood that these are exemplary and that the scope of the invention is limited only by the following claims.