Single zone HVAC controlled for operation in multiple zone arrangement

• US 4,530,395 A
• Filed: 12/29/1982
• Issued: 07/23/1985
• Est. Priority Date: 10/14/1982
• Status: Expired due to Term

• Current Assignee: Carrier Corporation (Carrier Global Corporation)
• Original Assignee: Parker Electronics Inc. (Carrier Global Corporation)
• Inventors: Parker, Jeffrey L., Parker, Edward
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US06/454,483
• Time in Patent Office: 937 Days
• Field of Search: 236/49, 236/1 B, 236/1 C, 236/151, 165/16, 165/22, 165/26, 364/557, 364/505
• US Class Current: 165/208
• 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 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/523 for displaying temperature data
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/67 Switching between heating and cooling modes
• CPC Class Codes: F24F 11/72 for controlling the supply of treated air, e.g. its pressure
• CPC Class Codes: F24F 11/74 for controlling air flow rate or air velocity
• CPC Class Codes: F24F 11/88 Electrical aspects, e.g. circuits
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2140/00 Control inputs relating to system states

Abstract

A monitoring and control system for a heating, ventilating and air conditioning (HVAC) unit which provides zone control in plural zones in which each zone includes a control thermostat that is interfaced with the monitoring system so that each zone thermostat controls the HVAC unit as well as a damper unit for that particular zone thereby enabling independent zonal control in a multiple zone system which uses a single zone HVAC unit. The monitor considers individual zone needs, damper positions, amount of demand in the zone, mode of the zone damper and other factors which affect the comfort of zone occupants and, in response to signals from the thermostats, decides how and when to control the HVAC unit so that, in effect, a single zone HVAC unit becomes a multiple zone system. The system is comprised of two or more computerized thermostats which control both the HVAC unit through the monitoring control and the air distribution system of each zone through the damper for each zone, creating a heating, cooling, variable air volume and variable temperature control system. The thermostats also operate under control of signals received from the monitor.

Claims

1. In a control system for monitoring and controlling the condition of air in each of a plurality of zones when using a single zone HVAC unit having a single supply air duct through which cool air or heated air is delivered into each zone, a thermostat means in each zone interfaced with and controlling a damper means in a duct supplying conditioned air to its respective zone and providing information to a control means, said control means including a monitor having a plurality of selectable control switches, said monitor being interfaced with the HVAC unit, each said thermostat means determining the condition of the air in its associated zone, said monitor activating the HVAC unit in accordance with the selected switches and the information provided from said zone theremostats to control the HVAC unit in the heating mode or cooling mode or ventilating mode.

2. In the system as defined in claim 1 wherein said monitor includes indicating means indicative of the status and requirements of each zone as provided by the information from said thermostat means therein.

3. In the system as defined in claim 1 wherein said monitor includes indicating means indicative of the status of the operating conditions of the HVAC unit.

4. In the system as defined in claim 1 wherein said monitor includes a sensor for sensing the temperature of the heating and/or cooling circuits of the HVAC unit and having an indicating means indicative of the status of the operating conditions of the HVAC unit, said sensor providing information to said monitor for controlling the high and low temperture limits for the HVAC unit.

5. In the system of claim 4 wherein said monitor includes status indicating means for each said thermostat means and said HVAC unit and said sensor probe.

6. In the system as defined in claim 1, wherein said monitor provides information to each said thermostat means as to the heating mode or cooling mode or ventilating mode which in turn controls the positioning of respective said damper means in the selected mode before operation of the HVAC unit in the selected mode.

7. In a control system for a single zone HVAC unit having a single supply air duct through which cool air or heated air is delivered to maintain desired temperature conditions in a plurality of zones in which each zone includes a thermostat and a damper assembly to control the conditioned air to respective said zones, said system comprising a monitor interfaced with the HVAC unit and each said thermostat and damper assembly, said monitor including a plurality of selectable switches for controlling the operation and performance characteristics of the HVAC unit in accord with the switches selected, said monitor receiving information from each thermostat and analyzing such information in accord with the switches selected before operating the HVAC unit in the heating, cooling or venitlating mode.

8. In the system of claim 7 wherein said monitor provides information to each said thermostats as to the selected mode which in turn position said dampers in the selected mode before operating the HVAC unit.

9. In the system as defined in claim 7 wherein said monitor includes a sensor for sensing the temperature of the heating and/or cooling circuits of the HVAC unit and having an indicating means indicative of the status of the operating conditions of the HVAC unit, said sensor providing information to said monitor for controlling the high and low temperature limits of the HVAC unit.

10. In the system of claim 9 wherein said monitor includes status indicating means for each said thermostat and the HVAC unit and said sensor probe.

11. A control system for monitoring and controlling the condition of air within each of a plurality of zones when using a single zone HVAC unit comprising:

(a) a governor thermostat associated with each of said zones,

(b) means associated with each zone controlled by the governor thermostat for controlling the flow of air into its respective zone,

(c) monitor means responsive to signals indicative of the condition of the air in each of said zones controlling the state of said HVAC unit, said monitor means including

(d) means responsive to the mode of said HVAC unit and said signals indicative of the condition of the air in each of said zones to control each said governor thermostat.

12. A control system as set forth in claim 11 wherein said monitor means is responsive to signals received from each said governor thermostat.

13. A control system as set forth in claim 12 wherein said monitor means includes a data base and said means responsive is further responsive to said data base.

14. A control system as set forth in claim 13 wherein each said governor thermostat includes a microprocessor, means in said governor thermostat for providing data to said microprocessor and means responsive to signals received from said monitor means to control said microprocessor.

15. A control system as set forth in claim 12 wherein each said governor thermostat includes a microprocessor, means in said governor thermostat for providing data to said microprocessor and means responsive to signals received from said monitor means to control said microprocessor.

16. A control system as set forth in claim 11 wherein said monitor means includes a data base and said means responsive is further responsive to said data base.

17. A control system as set forth in claim 11 wherein each said governor thermostat includes a microprocessor, means in said governor thermostat for providing data to said microprocessor and means responsive to signals received from said monitor means to control said microprocessor.

18. A control system as set forth in claim 16 wherein each said governor thermostat includes a microprocessor, means in said governor thermostat for providing data to said microprocessor and means responsive to signals received from said monitor means to control said microprocessor.

19. A method for controlling the positioning of a plurality of dampers of zone duct damper means prior to activating a single zone HVAC unit that supplies heated or cooled conditioned air through a single duct system having duct damper means and ducts to a plurality of zones and zone thermostats associated with respective dampers comprising the steps of:

A. determining the demand for heating or cooling from all zone thermostats;

B. selecting the heating or the cooling mode depending on such demand and setting all zone thermostats in the selected mode;

C. closing appropriate dampers if the zone thermostats controlling such appropriate dampers have no demand or demand a mode different than the mode selected to step B, and positioning open the other dampers;

D. activating the HVAC unit in the selected mode until all zone thermostats demanding the selected mode have been satisfied;

E. deactivating the HVAC unit; and

F. repeating steps A-E for the other mode when demand for the other mode has been selected in accord with steps A and B.

20. The method of claim 19 wherein step C includes the step of partially opening some of the other dampers depending upon the amount of demand by their respective thermostats and modulating such dampers between open and closed until the demand is satisfied.

21. The method of claim 20 further comprising the step of

G. comparing such demand from step A with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for heat or cooling prior to step B, and if the demands for heating and cooling are equal, the HVAC unit will be activated in step D in the mode setting of the monitor means.

22. The method of claim 19 further comprising the step of

G. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats from step A.

23. The method of claim 22 wherein the respective control of the zone thermostats in step G includes the steps of:

a. determining the zone temperature,

b. determining the duct temperature of the air in the supply duct, and

c. comparing the zone temperature to the duct temperature and

(1) when the duct temperature is warmer than the zone temperature, the thermostat operates the zone duct damper in the heating mode and substantially opens the zone duct damper upon the thermostat sending a zone demand for heat when the zone temperature is a predetermined amount below set point and substantially closes the zone duct damper upon the thermostat sensing no zone demand or a zone demand for cooling, and

(2) when the duct temperature is cooler than the zone temperature, the thermostat operates the zone duct damper in the cooling mode and substantially opens the zone duct damper upon the thermostat sensing a zone demand for cooling when the zone temperature is a predetermined amount above set point and substantially closes the zone duct damper upon the thermostat sensing no zone demand or zone demand for heat.

24. A method of monitoring and controlling the condition of air within each of a plurality of zones being supplied with heated or cooled conditioned air from a single zone HVAC unit via a single duct system having zone ducts and zone duct damper means therein controlled by zone thermostats and a monitor means monitoring and controlling all zone duct thermostats and the HVAC unit comprising the steps of:

A. setting the set point of each of the zone thermostats to the comfort level of the respective zone occupants;

B. monitoring the demand for heating or cooling from all zone thermostats by the monitor means which selects either of the heating or cooling mode of the HVAC unit;

C. positioning the zone duct damper means open if the zone thermostats are demanding the selected mode and closed for the other damper means;

D. activating the HVAC unit by the monitor means in the selected mode until all zone thermostats demanding the selected mode have been satisfied; and

E. deactivating the HVAC unit.

25. The method of claim 24 further comprising the steps of

F. selecting the mode for operation of the HVAC unit in step B in accord with the greater number of zone thermostats demanding cooling or heating;

G. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats from step A.

26. The method of claim 24 further comprising the step of

F. repeating steps B-E for the other mode when demand for the other mode has been selected in accord with step B.

27. The method of claim 24 wherein step C includes the step of

F. partially opening some of the damper means depending upon the amount of demand for the selected mode by their respective thermostats and modulating such damper means between open and closed until the demand is satisfied.

28. The method of claim 24 further comprising the step of

F. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit in step D in the mode setting of the monitor means.

29. The method of claim 24 further comprising the step of

F. modulating between open and closed positions the zone damper according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats.

30. The method of claim 29 wherein the respective control of the zone thermostats in step F includes the steps of:

a. determining the zone temperature,

b. determining the duct temperature of the air in the supply duct, and

c. comparing the zone temperature to the duct temperature and

(1) when the duct temperature is warmer than the zone temperature, the thermostat operates the zone duct damper in the heating mode and substantially opens the zone duct damper upon the thermostat sending a zone demand for heat when the zone temperature is a predetermined amount below set point and substantially closes the zone duct damper upon the thermostat sensing no zone demand or a zone demand for cooling, and

(2) when the duct temperature is cooler than the zone temperature, the thermostat operates the zone duct damper in the cooling mode and substantially opens the zone duct damper upon the thermostat sensing a zone demand for cooling when the zone temperature is a predetermined amount above set point and substantially closes the zone duct damper upon the thermostat sensing no zone demand or zone demand for heat.

31. The method of claim 24 wherein step C includes the step of

F. partially opening some of the damper means depending upon the amount of demand for the selected mode by their respective thermostats and modulating such damper means between open and closed until the demand is satisfied;

and further comprising;

G. repeating steps B-E for the other mode when demand for the other mode has been selected in accord with step B.

32. The method of claim 24 wherein step C includes the step of

F. partially opening some of the damper means depending upon the amount of demand for the selected mode by their respective thermostats and modulating such damper means between open and closed until the demand is satisfied;

and further comprising

G. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit in step B in the mode setting of the monitor means.

33. The method of claim 24 wherein step C includes the step of

F. partially opening some of the damper means depending upon the amount of demand for the selected mode by their respective thermostats and modulating such damper means between open and closed until the demand is satisfied;

and further comprising

G. modulating between open and closed positions the zone dampers according to the respective control of the zome thermostats when there is no insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats.

34. The method of claim 24 further comprising the step of

F. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit in step D in the mode setting of the monitor means;

and

G. repeating the steps B-E for the other mode when demand for the other mode has been selected in accord with step B.

35. The method of claim 24 further comprising the step of

F. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit in step D in the mode setting of the monitor means;

and

G. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats.

36. The method of claim 24 further comprising the step of

F. repeating steps B-E for the other mode when demand for the other mode has been selected in accord with step B

G. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats.

37. The method of claim 24 wherein step C includes the step of

F. partially opening some of the damper means depending upon the amount of demand for the selected mode by their respective thermostats and modulating such damper means between open and closed until the demand is satisfied;

further comprising

G. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit step D in the mode setting of the monitor means; and

H. repeating steps B-E for the other mode when demand for the other mode has been selected in accord with step B.

38. The method of claim 24 wherein step C includes the step of

F. partially opening some of the damper means depending upon the amount of demand for the selected mode by their respective thermostats and modulating such damper means between open and closed until the demand is satisfied;

further comprising

G. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit in step D in the mode setting of the monitor means; and

H. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats.

39. The method of claim 24 further comprising the step of

F. comparing such demand from step B prior to selecting the mode with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for either heat or cooling, and if the demands for heating and cooling are equal, the monitor means will activate the HVAC unit in step D in the mode setting of the monitor means;

G. repeating the steps B-E for the other mode when demand for the other mode has been selected in accord with step B; and

H. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats.

40. A method for controlling a single zone HVAC unit and a single duct system including a plurality of zone ducts having a respective zone duct damper means therein regulated by zone thermostats in respective zones and the zone thermostats controlling the HVAC unit via a monitor means, comprising the steps of

A. determing zone demands from a plurality of said zones by the thermostats and producing zone demand signals indicative of the demand for heating or cooling or no demand;

B. receiving zone demand signals in a monitor means;

C. comparing the number of signals demanding heating with signals demanding cooling;

D. selecting the heating or cooling mode;

E. opening said damper means of zones demanding the selected mode and closing said damper means of zones demanding the unselected mode and zones having no demand;

F. activating by said monitor means the HVAC unit in the selected mode until all zone thermostats demanding the selected mode have been satisfied; and

G. deactivating the HVAC unit.

41. The method of claim 40 further comprising the step of

H. repeating steps A-G for the other mode when demand for the other mode has been determined, received, compared and selected in accord with steps A-D.

42. The method of claim 40 further comprising the step of

H. comparing such demand from step A with the selectable mode setting of a monitor means controlling all of the zone thermostats and the HVAC unit and selected for heat or cooling prior to step B, and if the demands for heating and cooling are equal, the HVAC unit will be activated in step D in the mode setting of the monitor means.

43. The method of claim 40 wherein step E includes the step of partially opening some of the other dampers depending upon the amount of demand by their respective thermostats and modulating such dampers between open and closed until the demand is satisfied.

44. The method of claim 40 further comprising the steps of

H. modulating between open and closed positions the zone dampers according to the respective control of the zone thermostats when there is insufficient demand to require activation of the HVAC heating or cooling circuits by the zone thermostats from step A.

45. The method of claim 40 wherein the respective control of the zone thermostats in step H includes the steps of:

a. determining the zone temperature,

b. determining the duct temperature of the air in the supply duct, and

c. comparing the zone temperature to the duct temperature and

(1) when the duct temperature is warmer than the zone temperature, the thermostat operates the zone duct damper in the heating mode and substantially opens the zone duct damper upon the thermostat sending a zone demand for heat when the zone temperature is a predetermined amount below set point and substantially closes the zone duct damper upon the thermostat sensing no zone demand or a zone demand for cooling, and

(2) when the duct temperature is cooler than the zone temperature, the thermostat operates the zone duct damper in the cooling mode and substantially opens the zone duct damper upon the thermostat sensing a zone demand for cooling when the zone temperature is a predetermined amount above set point and substantially closes the zone duct damper upon the thermostat sensing no zone demand or zone demand for heat.