FAN COIL THERMOSTAT WITH ACTIVITY SENSING

• US 20090032605A1
• Filed: 08/03/2007
• Published: 02/05/2009
• Est. Priority Date: 08/03/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Sullivan, Daniel J., Geadelmann, Levi H.
• Granted Patent: US 9,182,141 B2
• Time in Patent Office: Days
• US Class Current: 236/46.R
• CPC Class Codes: F24F 1/0007 Indoor units, e.g. fan coil units self-contained units F24F1/02
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/39 Monitoring filter performance
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/62 characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
• CPC Class Codes: F24F 11/64 using pre-stored data
• CPC Class Codes: F24F 11/65 for selecting an operating mode
• CPC Class Codes: F24F 11/77 by controlling the speed of ventilators
• CPC Class Codes: F24F 11/83 by controlling the supply of heat-exchange fluids to heat-exchangers
• CPC Class Codes: F24F 11/84 using valves
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2120/00 Control inputs relating to users or occupants
• CPC Class Codes: F24F 2120/10 Occupancy
• CPC Class Codes: F24F 2120/12 Position of occupants
• CPC Class Codes: F24F 2120/20 Feedback from users
• CPC Class Codes: F24H 15/265 Occupancy
• CPC Class Codes: G05B 19/048 Monitoring; Safety
• CPC Class Codes: G05B 2219/2614 HVAC, heating, ventillation, climate control
• CPC Class Codes: G05D 23/1904 : variable in time
• CPC Class Codes: Y02B 30/70 : Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

Fan coil thermostats can provide energy savings by, for example, not unnecessarily heating and/or cooling an unoccupied room or other space. Fan coil systems employing such a fan coil thermostat may be more energy efficient. 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, a fan that blows air across the fan coil and a fan coil thermostat. The fan coil thermostat may include a controller that implements a control algorithm that may include an unoccupied temperature setting. The controller may be programmed to permit a user to enter a user-chosen temperature setting. In response, the controller may initiate a timer, and may automatically return to the unoccupied temperature setting once the timer has expired.

Claims

1. A fan coil thermostat for use with a fan coil system, the fan coil thermostat comprising:

a controller implementing a control algorithm that is adapted to at least partially control one or more components of the fan coil system, the control algorithm including an unoccupied temperature setting;

a timer controlled by the controller; and

a user interface comprising one or more buttons, the user interface adapted to provide a signal to the controller when one or more of the buttons are operated, the signal providing the controller with a user-chosen temperature setting and also providing the controller with an indication of occupancy;

wherein the controller temporarily changes the temperature setpoint from the unoccupied temperature setting to the user-chosen temperature setting, and, in response to the indication of occupancy, initiates the timer, the controller returning the temperature setpoint to the unoccupied temperature setting once the timer expires.

2. The fan coil thermostat of claim 1, wherein the timer expires after about 12 hours.

3. The fan coil thermostat of claim 1, wherein the timer expires after about 24 hours.

4. The fan coil thermostat of claim 1, wherein the timer is adapted to expire at a predetermined time of day.

5. The fan coil thermostat of claim 4, wherein the predetermined time of day corresponds to a checkout time.

6. The fan coil thermostat of claim 1, wherein the controller instructs the timer to restart if a subsequent indication of occupancy is received before the timer expires.

7. The fan coil thermostat of claim 1, wherein the one or more buttons comprise one or more of a temperature up button, a temperature down button and a fan speed button.

8. The fan coil thermostat of claim 1, wherein the controller is adapted to store the unoccupied temperature setting and to permit temporarily changing to a user-chosen temperature setting, but does not accommodate any other programmed temperature setback information.

9. The fan coil thermostat of claim 8, wherein the controller is not configured to accommodate programmed temperature setback information pertaining to differing temperature set points corresponding to particular periods of time of a day.

10. The fan coil thermostat of claim 8, wherein the controller is adapted to operate only at the unoccupied temperature setting or temporarily at the user-chosen temperature setting.

11. The fan coil thermostat of claim 1, wherein the unoccupied temperature setting comprises a temperature set point chosen to conserve energy, the unoccupied temperature set point determined and set by a contractor or other maintenance personnel.

12. The fan coil thermostat of claim 11, wherein the temperature set point comprises a heating temperature set point and a cooling temperature set point.

13. A fan coil system, comprising:

a fan coil 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;

a fan that blows air across the fan coil; and

a fan coil thermostat, the fan coil thermostat including a user interface and a controller that is adapted to maintain a temperature set point by controlling the valve and/or the fan;

wherein the controller is programmed to accept a user-chosen temperature setting via the user interface, the controller temporarily changing the temperature set point from an unoccupied temperature setting to the user-chosen temperature setting, the controller maintaining the user-chosen temperature setting for a predetermined length of time before automatically returning to the unoccupied temperature setting.

14. The fan coil system of claim 13, wherein the fan coil thermostat further comprises a timer controlled by the controller.

15. The fan coil system of claim 14, wherein the controller, in response to receiving the user-chosen temperature setting from the user interface, initiates the timer.

16. The fan coil system of claim 15, wherein the controller changes the temperature set point back to the unoccupied temperature setting once the timer has expired.

17. The fan coil system of claim 13, wherein the timer is adapted to expire after a period of time of between about 12 hours and about 24 hours.

18. The fan coil system of claim 13, wherein the controller is adapted to maintain the temperature set point only at the unoccupied temperature setting or at the user-chosen temperature setting.

19. A method of operating a fan coil system comprising a fan coil accommodating fluid flow therethrough and a fan adapted to blow air across the fan coil, the method comprising the steps of:

controlling fluid flow through the fan coil and/or regulating the fan speed in accordance with an unoccupied temperature setting;

accepting a temporary temperature set point;

initiating a timer in response to accepting the temporary temperature set point;

controlling fluid flow through the fan coil and/or regulating the fan speed in accordance with the temporary set point; and

automatically reverting to the unoccupied temperature setting point once the timer expires.

20. The method of claim 19, wherein initiating a timer step comprises initiating a timer that expires after a time period of about 12 hours.

21. The method of claim 19, wherein initiating a timer step comprises initiating a timer that expires after a time period of about 24 hours.

22. The method of claim 19, further comprising restarting the timer if another temporary temperature set point is accepted before the timer expires.