The present disclosure pertains generally to thermostats and more particularly to thermostats adapted for use with fan coils.
A variety of buildings such as hotels, apartment buildings and the like are heated and cooled using fan coil systems. In a fan coil system, a heat transfer fluid such as water is pumped or otherwise forced through a fan coil. A fan is used to blow air across the fan coil. If the heat transfer fluid was heated, heated air will blow out of the fan coil system. Conversely, if the heat transfer fluid was cooled, cool air will blow out of the fan coil system.
Like other HVAC systems, fan coil systems often consume significant amounts of energy. For many buildings, such as hotels and other structures, a number of rooms may, at any given time, be unoccupied. A significant amount of energy may be saved by not running a fan at a higher than necessary speed, particularly when a room or other space is not occupied.
The present disclosure pertains to fan coil thermostats that can provide energy savings by, for example, not unnecessarily running a fan longer than necessary and/or at a higher speed than necessary, particularly when a room or other space is not occupied. Fan coil systems employing such a fan coil thermostat may be more energy efficient.
In an illustrative but non-limiting example of the present disclosure, a fan coil thermostat is configured for use with a fan coil system. In some cases, a fan coil system may include a fan coil that is configured for fluid communication with a source of heated fluid and/or a source of cooled fluid, a valve that controls fluid flow through the fan coil and a fan that blows air across the fan coil.
The fan coil thermostat may include a controller that implements a control algorithm that is adapted to at least partially control one or more components of the fan coil system and that may include an Auto fan speed mode. The fan coil thermostat may include a user interface as well as a timer that is controlled by the controller. The controller may be programmed to permit a user to manually select a fan speed setting using the user interface. In response, the controller may initiate the timer, and may return to the Auto fan speed mode once the timer has expired.
The above summary is not intended to describe each disclosed embodiment or every implementation of the present invention. The Figures and Detailed Description that follow more particularly exemplify these embodiments.
The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular illustrative embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
The following description should be read with reference to the drawings, in which like elements in different drawings are numbered in like fashion. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Although examples of construction, dimensions, and materials may be illustrated for the various elements, those skilled in the art will recognize that many of the examples provided have suitable alternatives that may be utilized.
The illustrative fan coil system 10 includes a fan coil 12. Fan coil 12 is a heat exchanger through which heated or cooled fluid flows. A fan 14 blows air across fan coil 12 as schematically shown by arrows 16. In some cases, fan 14 pulls ambient air from within the space and/or from outside the building. The ambient air is then heated or cooled by the fan coil 12 and provided into the space. In some cases, fan coil system 10 may be disposed within a housing (not shown) having a first vent or opening upstream of fan 14 and a second vent or opening downstream of fan coil 12. Fan 14 may pull air through the first vent or opening and then exhaust the heated or cooled air through the second vent or opening and into the space. The components may be arranged either horizontally or vertically within such a housing, as desired or perhaps as dictated by space considerations.
In order to accommodate fluid flow through fan coil 12, fan coil system 10 includes a supply line 18 and a return line 20. During the heating season, supply line 18 provides a source of heated fluid (such as water) from a suitable source such as a boiler or water heater, geothermal and/or the like. During the cooling season, supply line 18 provides a source of cooled fluid (such as water) from a suitable source such as an evaporative cooling tower or the like.
A valve 22 is disposed within supply line 18, upstream of fan coil 12, in order to control fluid flow through fan coil 12. In some cases, valve 22 may provide binary, i.e., on/off control while in other cases it is contemplated that valve 22 may be configured to provide a plurality of flow rates into fan coil 12.
Fan coil system 10 may include a fan coil thermostat 24 that controls operation of valve 22 and/or operation of fan 14 in order to achieve a desired temperature level within a space that is conditioned by fan coil system 10. Fan coil thermostat 24 is better described with respect to
The illustrative fan coil thermostat 24 may include a controller 32. In some cases, controller 32 may implement a control algorithm that is adapted to at least partially control one or more components of fan coil system 10 and that may include an Auto fan speed mode setting. In some cases, the Auto fan speed mode may include an algorithm that determines fan speed based at least in part on if valve 22 (
Controller 32 may be adapted to provide information to and/or receive information from user interface 26. Controller 32 may, for example, display a current temperature and/or a current temperature set point on display 28. Other examples of information that may be provided by controller 32 include a current fan speed, current fan mode, equipment status (on/off), current time, and the like. Examples of information that may be received from keypad 30 may include changes in a temperature set point, changes in fan speed and the like.
In some cases, the illustrative fan coil thermostat 24 may include a memory block 34. Memory block 34 may be used, for example, to store one or more unoccupied temperature set points, a current temperature set point, and/or programming that instructs controller 32 how to regulate valve 22 (
In some instances, fan coil thermostat 24 may include a sensor 36 that provides controller 32 with information pertaining to current conditions within a space conditioned by fan coil system 10 (
Fan coil thermostat 24 may include a timer 38. In some cases, timer 38 may be an electromechanical timer while in other instances timer 38 may be an electronic timer or may even be manifested in programming run by controller 32. In some instances, if a user operates one or more buttons of keypad 30, such as changing a temperature set point or perhaps changing the speed of fan 14 (
When the user first changes the fan speed setting, the controller 32 may temporarily change the fan speed from that specified by the default Auto fan speed mode to the manually-selected fan speed. In some cases, the manually-selected fan speed may be selected irrespective of a difference, if any, between an ambient temperature and a current temperature set point. For example, an individual may decide to set the fan speed to high even if the ambient temperature is equal or nearly equal to the current temperature set point. In some cases, the manually-selected fan speed may specify a fan speed that is higher and/or lower than what would otherwise be specified by the Auto fan speed mode. In some instances, the manually selected fan speed setting specifies a non-zero fan speed under conditions in which the Auto fan speed mode would specify a zero fan speed.
In addition to changing the fan speed in response to the signal from keypad 30 (
The illustrative fan coil thermostat 40 also includes several buttons that may be considered as examples of keypad 30 (
As illustrated, fan coil thermostat 40 includes a temperature up button 50 and a temperature down button 52. A user may select and/or alter a temperature setting by pressing temperature up button 50 and/or temperature down button 52, as appropriate. A power button 54 may also be provided. It is contemplated that fan coil thermostat 40 may instead have a touch screen LCD that provides the functionality of display 44 as well as fan speed up button 46, fan speed down button 48, temperature up button 50, temperature down button 52, and power button 54. In some cases, the various buttons may be provided as touch regions on the touch screen display.
Control passes to block 62, where controller 32 (
Control passes to block 62, where controller 32 (
While the present disclosure has been described with respect to illustrative fan coil systems that include one or more pipes carrying heated water for heating and/or cooled water for cooling, it should be noted that the inventive concepts described herein are not limited to such systems. Some systems may be hybrid-type systems, with an A/C compressor for cooling and heated water for heating. Some systems may be through-the-wall systems, having one or more of a compressor for air conditioning, an electric or gas heating element for heating, and a heat pump. Fan coil thermostat 40 may, for example, be used with these systems as well as the systems described herein.
The present disclosure should not be considered limited to the particular examples described above, but rather should be understood to cover all aspects of the invention as fairly set out in the attached claims. Various modifications, equivalent processes, as well as numerous structures to which the present invention can be applicable will be readily apparent to those of skill in the art to which the present invention is directed upon review of the instant specification.
This is a continuation application of co-pending U.S. patent application Ser. No. 11/833,685, filed Aug. 3, 2007, and entitled “FAN COIL THERMOSTAT WITH AUTOMATIC FAN RESET”, which is incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
Parent | 11833685 | Aug 2007 | US |
Child | 15368472 | US |