Abstract:
Air temperature is adjusted by employing a tangential fan having a vertically-oriented axis to direct air over a coil assembly, directing a fluid through the coil assembly, and adjusting the temperature of the fluid to cool or heat the air, wherein the coil assembly provides thermal communication between the air and the fluid.

Description:
This application is a divisional application of and claims the priority of U.S. patent application Ser. No. 09/488,282, filed Jan. 20, 2000, the entire contents of which are incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a modular climate control unit, specifically to a unit exhibiting improved efficiency and a small footprint. 
     BACKGROUND OF THE INVENTION 
     A variety of climate control systems are used for heating and cooling in taller buildings, in which circulating water is used as a heat exchange medium for both heating and cooling. The water is heated or cooled at a central apparatus, and a pump is used to circulate the water through a closed circuit connected to heat exchangers in each room and back to the apparatus for reheating or recooling. It is desirable that the climate control unit in each room occupy as little working or living space as possible. Naturally, it is also desirable that the unit be quiet, so as not to distract the occupant. Furthermore, because of the large number of rooms in a given building, it is desirable to have a climate control unit which can be installed easily and quickly, minimizing installation time during construction, yet allowing for easy maintenance throughout the life of the building. To reduce construction costs and simplify plumbing, it is also desirable to have a climate control unit which can be used for both heating and cooling. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention is an apparatus for climate control. The apparatus includes an air inlet, a tangential fan, a fan coil assembly, a barrier to prevent recirculation of air within the apparatus after it passes through the fan coil assembly, a joint to provide fluidic communication with a source of recirculating fluid, and an air outlet. The coil assembly connected in series to the circuit through which the recirculating fluid circulates and provides thermal communication between fluid flowing from and to the source of recirculating fluid and the circulating air. Air is circulated from the inlet through the coil assembly to the outlet by the fan. The apparatus may also include a plurality of fans, and these fans may be oriented vertically and disposed one over the other. For example, the apparatus may comprise two, three, or four fans. The fan coil assembly may provide thermal communication between fluid returning to the source of recirculating fluid and the circulating air. The assembly may include a plurality of pipes which are connected to first and second manifolds located at each end of the fan coil assembly. For example, the coil assembly may comprise six pipes or two sets of six pipes. In the latter case, the first set of pipes is connected to a set of manifolds at each end of the fan coil assembly, and the second set of pipes is connected to separate manifolds which are also disposed at each end of the fan coil assembly. The joint may comprise a pipe connector, and the fan coil assembly may include a plurality of pipes in fluidic communication with the source of re-circulating fluid and a plurality of fins in thermal communication with the plurality of pipes. The fins may be arranged parallel to each other with a density of about 12 fins/inch. The fins may comprise condensate drip lips. The air inlet may have a smaller surface area than the air outlet, and the apparatus may include a baffle disposed along an airflow path between the fan coil assembly and the outlet. The apparatus may be configured to fit between two adjacent studs within a wall of a room. This may include configuring the apparatus to be at most 9.2 cm deep and 35 cm wide. The apparatus may be about 86.4, 130, or 173 cm tall and include two, three, or four fans, respectively. The apparatus may also comprise of an adjustable thermal static control or an adjustable speed control, enabling the fan to be operated at a variety of speeds. The source of recirculating water may include a heat exchanger. 
     In another aspect, the invention is a method for adjusting air temperature, including employing a tangential fan to direct air over a fan coil, directing fluid through the fan coil, and adjusting the temperature of the fluid to cool or heat the air. The fan coil provided thermal communication between the air and the fluid. The method may further include recirculating the fluid or orienting the fan vertically. Recirculated fluid may be passed through a heat exchanger. The method may also include the employment of a plurality of fans. The method may also include drying the air from a first generally enclosed space and directing the air into either the first or a second generally enclosed space. The method may also include adjusting the speed of the fan or controlling the air temperature of the generally enclosed space thermostatically. This step of controlling may include causing the fan to go on and off in response to a preset change in air temperature. The method may further include disposing the fan and the fan coil within a space defined by two adjacent studs in a wall. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The invention is described with reference to the several figures of the drawing, in which, 
     FIG. 1 a  is a schematic diagram of the air path in an exemplary climate control unit according to the invention; 
     FIG. 1 b  is a diagram of the interior of the exemplary climate control unit, showing its relationship to an exterior cover of the unit; 
     FIG. 2 is a diagram of the water flow path in a climate control unit which has been integrated into a central heating and cooling system; 
     FIG. 3 is a blow-up view of the exemplary climate control unit; 
     FIG. 4 depicts a configuration of the unit for reverse air flow operation; 
     FIG. 5 is a diagram of the space required for installation of a climate control unit according to the invention; and 
     FIG. 6 is a schematic diagram of an embodiment of the climate control unit of the invention in which the unit directs air into two rooms; the louvers have been omitted for clarity. 
    
    
     DETAILED DESCRIPTION 
     The invention is a vertical, wall recessed climate control unit  5  connected to a water circulation system. Several units, located on several floors of a building, define a water circulation circuit connected to a water heating or cooling system  7  in the building; heat exchange is performed by an aluminum fin/copper tube water coil assembly and vertically oriented tangential fans which circulate air from the room through the coil. Each unit can be controlled to maintain a specific room at a given temperature. FIG. 1 a  shows a diagram of the air path in a climate control unit  5  according to the invention. The air is drawn into the unit  5  through an input louver  10  by a vertical fan  12 , which circulates the air through a coil assembly  14 . FIG. 1 b  shows a diagram of the climate control unit  5 , from which a grill  16  has been removed to ease viewing. Control panel  22  is actually mounted to the “internal” portion of the climate control unit  5 . The unit includes vertical fans  12  and  24 . Fans  12  and  24  are tangential fans, which reduce the noise generated by the unit  5 . The unit may include additional fans to increase throughput. Fluid is provided to coil assembly  14  through pipe assembly  26 . Pipe assembly  26  includes upper manifolds  28  and  30  and corresponding lower manifolds  29  and  31  (FIG.  3 ). The manifolds  28 - 31  are connected to the water circulation circuit by connecting pipes  32 ,  34 ,  36 , and  38 . In addition, upper manifolds  28  and  30  are connected to their respective lower manifolds  29  and  31  by a set of six copper tubes  33   a-f  and  35   a-f  which extend through the coil assembly  14  and are in thermal communication with fins  40 . The twelve copper tubes  33  and  35  distribute the heat exchange capacity of the water circulating through the building across the surface of fins  40 , providing a more regular heat distribution than would be provided by fewer (e.g., 2) tubes. The combination of the manifolds  28 ,  29 ,  30 , and  31 , upper and lower pipe connectors  32 ,  34 ,  36 , and  38 , and the twelve copper tubes  33  and  35   a-f  carry water from and to the building&#39;s water heating or cooling system  7 . For example, water may come from the system  7  via any intervening units through pipe connector  32  and manifold  28  (FIG.  2 ). One skilled in the art will understand that system  7  may include one or more of a compressor, boiler, heat exchanger, and other elements necessary to reheat or recool water returning from climate control units. The water is distributed from the manifold  28  into copper tubes  33   a-f  which reunite at the bottom of the coil assembly  14  in lower manifold  29 . Water is then conducted to a lower, adjacent unit through pipe connector  36 . Water returning to the system  7  enters the unit  5  through pipe connector  38  and is distributed to copper tubes  35   a-f  by lower manifold  31 . The water flows upward through the coil assembly  14  into upper manifold  30 , from which it is conducted to adjacent, higher units through pipe connector  34 . Alternatively, either pipe connectors  36  and  38  or pipe connectors  32  and  34  may be connected to each other to prevent circulation of water to adjacent units or to recirculate the water if there is no adjacent unit. Of course, the central water heating or cooling system  7  may be located beneath the building, reversing the flow direction described above. 
     FIG. 3 shows the individual components of the climate control unit  5 . The unit  5  is assembled within a one-piece chassis  42  which can be inserted into a wall cavity during installation. The chassis  42  is preferably fabricated from zinc coated sheet metal. Vertical tangential fans  12  and  24  are fixed to the chassis  42  via screw joints. Coil cover support brackets  44  and  45  are also preferably fabricated from zinc coated mild sheet steel and are formed with flanges to secure them and a coil cover  46  to the chassis. As noted above, air enters the unit  5  through input louver  10  in grill  16 . The air is drawn into fans  12  and  24  and directed by them through coil assembly  14 . Coil cover  46  prevents the escape of air from the unit  5  as it leaves the fans  12  and  24  and directs air flow from the fans  12  and  24  through coil assembly  14 . It is preferably manufactured from zinc coated mild sheet steel (“galvanized steel”) and secured with screw joints to coil cover support brackets  44  and  45 . An internal barrier  48  prevents recirculation of air from coil assembly  14  through the tangential fans  12  and  24 . Control panel bracket  50  helps secure control panel  52 , which is mounted onto chassis  42 . It also serves as a second internal barrier, helping to prevent recirculation of air from the coil assembly through the tangential fans. In the two-fan embodiment shown in the figures, control panel bracket fits between tangential fans  12  and  24 . In a unit with more fans, the bracket  50  (and control panel  22 ) may be situated between any two fans. Control panel bracket  50  is preferably manufactured from zinc coated mild sheet steel and secured with screw joints to the chassis  42 . Lower outlet internal barrier  54  is secured to the chassis with screw joints on its formed flanges and is preferably manufactured from zinc coated mild sheet steel. The lower internal barrier  54  prevents air from escaping through the bottom of the unit  5  after it has passed through the coil assembly  14 . Upper outlet internal barrier  56  is similarly fabricated and mounted and prevents the escape of air through the top of the unit  5 . Grill  16  covers the complete internal mechanism of the unit  5  and is screwed to the chassis  42 . It includes inlet louver  10  and outlet louvers  18  and  20  to provide air circulation into and out of the unit  5  and an opening for access to control panel  22 . The grill  16  is preferably paint finished and manufactured from zinc coated mild sheet steel; the edges are folded over for both safety and airtightness. 
     The unit can be used for heating, cooling, or dual climate control. For units incorporating a cooling function, lower outlet internal barrier  54  will preferably include a waterproofing coating. In addition, fins  40  will preferably incorporate condensate drip lips. 
     The output louvers  18  and  20  are designed to allow air to circulate from and to the same room. However, it is not necessary to pass cooled or heated air back into the room from which it came. The unit  5  can discharge a portion of the heated or cooled air received through input louver  10  into an adjacent room using a smaller grill and bracket assembly  16  which is secured to the rear of chassis  42  over an opening  62  (FIG.  4 ). To use the reverse air flow mode, a panel  61  is disposed over a portion of output louvers  18  and  20 , preventing full air escape therethrough. Then, the unit  5  will direct heated or cooled air from a first room  64  rearwards through rear grill bracket assembly  60  into a second room  66  (FIG.  6 ). 
     While the temperature of the flowing water determines whether the unit functions as a heater or air conditioner, more precise control of room temperature is available via the control panel  52 . A thermostat is available to increase the precision of temperature control. A separate switch on panel  52  allows the room&#39;s occupant to adjust the air flow generated by the fans  12  and  24 . In a preferred embodiment, the fans run at two speeds. However, one skilled in the art will easily observe that the fans can be designed to run at a variety of speeds. 
     The climate control unit has several advantages over prior art units. Use of vertically oriented tangential fans reduces the width of the unit, enabling it to fit between two studs in a wall without having to project into the room and reducing the footprint of the unit  5  while increasing air flow efficiency. Fans can be added to the unit without increasing its width. The copper tubes  33   a-f  and  35   a-f  all contribute to heat exchange. Both the water traveling from system entering the unit  5  at pipe connector  36  and leaving it at  32  and the returning water flowing via pipe connectors  34  and  38  contribute to heat exchange. The twelve tubes  33   a-f  and  35   a-f  are evenly distributed over each individual fin  40 , minimizing thermal diffusion lengths from any point on fin  40  to a tube. In comparison, conventional units frequently require that either the coolant supply or return system be external to the coil assembly, where it cannot contribute to heat exchange. 
     In addition, only four connections are required to integrate the unit  5  into a complete heating and cooling system for a building. An adjacent unit on an upper floor is connected through its own pipe connections to pipe connectors  32  and  34 , and an adjacent unit on a lower floor is attached through joints to connectors  36  and  38 . In addition to the increased density of the copper pipes, an increased density of fins  40  contributes towards improved thermal conduction. 
     Prior art climate control units have approximately four to six aluminum fins per inch of tubing. In addition, prior art climate control units utilize a lower front grill intake and an upper front grill outlet. That is, the input and output louvers are not side by side; the output louvers are disposed above the input louvers. In a preferred embodiment, the unit of the invention has about 12 fins per inch, increasing heat exchange with a given volume of air, and exploits the full vertical length of grill  16  by using one half for the inlet and the other half for the outlet. These two innovations increase the efficiency of heat exchange for both air cooling and heating. The double size outlet, in comparison to the inlet, further enhances air flow and fan performance. 
     As noted above, unit  5  can fit between two studs (FIG. 5, x=14 in. [35 cm]) within a wall (y=3⅝ in. [9.2 cm]) and only requires a single cover, grill  16 . The unit  5  itself can be produced in a variety of heights h (e.g., 34 in. [86.4 cm], 51{fraction (3/16)} in. [130 cm], 68⅛ in. [173 cm]). Taller units can incorporate additional fans. For example, the 130 cm fan may comprise three fans, and the 173 cm fan may include four. The added fans increase the air flow capacity of the unit. For example, if a two fan unit can generate airflows of 1084 and 1578 l/min at its minimum and maximum speed settings, a three fan unit with the same type of fans will generate airflows of 1626 and 2367 l/min. Likewise, a four fan unit will generate airflows of 2168 and 3156 l/min at its minimum and maximum settings, respectively. The compact, self-contained design of the unit of the invention eases both installation and maintenance. To access any of the components for repair or replacement, it is only necessary to unscrew and remove grill  16 . 
     In addition, it is not necessary that the unit be vertically oriented. If the fans are oriented horizontally, then the unit can be configured to extend across part of the width of a wall in a room. Of course, in this case, the unit will not fit between normal wall studs. The horizontal unit is preferably incorporated into the original design of the building and installed as part of the original construction. Furthermore, connecting pipes  32 ,  34 ,  36 , and  38  should be fitted with elbows to facilitate connection to the building&#39;s water circulation system. 
     Other embodiments of the invention will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.