HVAC control with comfort/economy management

• US 8,560,127 B2
• Filed: 01/13/2011
• Issued: 10/15/2013
• Est. Priority Date: 01/13/2011
• Status: Active Grant

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Leen, Cary, Zywicki, Stan, Schnell, Robert J.
• Primary Examiner(s): Ali, Mohammad
• Assistant Examiner(s): Booker, Kelvin
• Application Number:
  US13/006,402
• Publication Number:
  US 20120185101A1
• Time in Patent Office: 1,006 Days
• Field of Search: 700/76, 700/278, 165/239, 165/240, 165/265, 236/46.R
• US Class Current: 700/278
• 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 11/62 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 11/65 for selecting an operating mode
• CPC Class Codes: F25B 29/00 Combined heating and refrigeration systems, e.g. operating alternately or simultaneously
• CPC Class Codes: G05D 19/02 characterised by the use of electric means
• CPC Class Codes: G05D 23/1904 variable in time
• CPC Class Codes: G05D 23/1917 using digital means

Abstract

A programmable thermostat may be configured to control one or more pieces of HVAC equipment in accordance with a programmable schedule. The HVAC equipment may be capable of modifying a temperature of an inside space with at least a primary stage and an auxiliary stage. The programmable thermostat may include a memory for storing operating parameters of the programmable thermostat, a user interface configured to accept modification of operating parameters, including one or more droop values, and a controller coupled to the memory and the user interface. The controller attempts to control the temperature of the inside space with the primary stage of the HVAC equipment, but if the temperature of the inside space deviates from a desired setpoint temperature value by more than or equal to a programmed droop value, the controller may activate the auxiliary stage. In some instances, the user interface of the programmable thermostat may be configured to allow a user to selectively override one or more of the applicable droop values. In some instances, the droop value that is used may depend on the current operation condition of the controller.

Claims

1. A programmable thermostat configured to control one or more pieces of HVAC equipment in accordance with a programmable schedule, the HVAC equipment capable of modifying a temperature of an inside space with at least a primary stage and an auxiliary stage, the programmable thermostat comprising:

a memory for storing operating parameters of the programmable thermostat, including one or more droop values;

a user interface configured to accept modification of one or more operating parameters; and

a controller coupled to the memory and the user interface, the controller programmed to activate the HVAC equipment to attempt to control the temperature of the inside space under one or more of at least three conditions, including a steady state condition, a programmed recovery condition, and a manual setpoint change condition;

wherein;

the controller is programmed to attempt to control the temperature of the inside space with the primary stage of the HVAC equipment; and

for one or more of the programmed recovery condition and the manual setpoint change condition, the controller is programmed to;

determine a temperature ramp based, at least in part, on one or more of the droop values stored in the memory; and

activate the auxiliary stage if the temperature of the inside space drops below the temperature ramp.

2. The thermostat of claim 1, wherein the one or more droop values include a steady state droop value, a programmed recovery droop value, and a manual setpoint change droop value;

and

wherein the controller uses the corresponding droop value in each of the programmed recovery condition and the manual setpoint change condition to determine the temperature ramp, unless the corresponding droop value is overridden by a user.

3. The thermostat of claim 1, wherein the one or more droop values includes a single installer droop value;

and

wherein the droop value in any of the steady state condition, the programmed recovery condition, and the manual setpoint change condition is the single installer droop value, unless overridden by a user selection.

4. The thermostat of claim 1, wherein the programmable thermostat is configured to allow a user to selectively override one or more of the one or more droop values.

5. The thermostat of claim 4, wherein the programmable thermostat is configured to allow an installer to selectively prevent a user from selectively overriding one or more of the one or more droop values.

6. The thermostat of claim 4, wherein the programmable thermostat is configured to allow a user to select a standard control option for at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition, wherein when the standard control option is selected, the controller is programmed not to override at least one of the one or more droop values.

7. The thermostat of claim 4, wherein the programmable thermostat is configured to allow a user to select a comfort control option for at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition, wherein when the comfort control option is selected, the controller is programmed to override at least one of the one or more droop values with a smaller value.

8. The thermostat of claim 4, wherein the programmable thermostat is configured to allow a user to select an economy control option for at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition, wherein when the economy control option is selected, the controller is programmed to override at least one of the one or more droop values with a larger value.

9. The thermostat of claim 4, wherein the programmable thermostat is configured to allow a user to select an override droop parameter for at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition, wherein when a corresponding override control option is selected, the controller is programmed to override at least one of the one or more droop values with a value that is dependent upon the selected override droop parameter.

10. A method for operating an HVAC system, the HVAC system having one or more HVAC units with at least a primary stage and an auxiliary stage for modifying a temperature of an inside space, the HVAC system having an HVAC controller for controlling the one or more HVAC units in accordance with a programmable schedule under at least three conditions including a steady state condition, a programmed recovery condition, and a manual setpoint change condition, the method comprising:

maintaining in a memory of the HVAC controller one or more installer droop values;

the controller attempting to control the temperature of the inside space with the primary stage; and

for one or more of the programmed recovery condition and the manual setpoint change condition, the controller;

determining a temperature ramp;

assessing whether adequate progress is being made toward a target temperature at a target time based at least in part on the temperature ramp; and

activating the auxiliary stage if adequate progress is not being made.

11. The method of claim 10, wherein the one or more installer droop values include separately definable installer droop values for the steady state condition, the programmed recovery condition, and the manual setpoint change condition.

12. The method of claim 10, wherein the one or more installer droop values include a single installer droop value that is used for the steady state condition, the programmed recovery condition, and the manual setpoint change condition.

13. The method of claim 10, wherein the user interface of the HVAC controller is configured to allow a user to override one or more of the one or more installer droop values.

14. The method of claim 13, further including the step of disabling the HVAC controller from allowing the user to override one or more of the one or more installer droop values.

15. The method of claim 10, further including the steps of:

receiving manual input via the user interface of a comfort control setting for at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition; and

overriding one or more of the installer droop values with a reduced droop value for using during at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition.

16. The method of claim 10, further including the steps of:

receiving manual input via the user interface of an economy control setting in at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition; and

overriding one or more of the installer droop values with an increased droop value for using during at least one of the steady state condition, the programmed recovery condition, and the manual setpoint change condition.

17. The method of claim 10, wherein the temperature ramp is based at least in part on one of the one or more installer droop values or an override droop value.

18. The method of claim 10, wherein assessing whether adequate progress is being made toward the target temperature at the target time includes comparing an instantaneous temperature of the inside space with a temperature offset from the temperature ramp by an amount related to one of the one or more installer droop values or an override droop value.

19. A method for controlling an HVAC system having a heat pump and an auxiliary heater configured to modify a temperature of an inside space, the HVAC system including a thermostat with an installer setup mode, a user mode., and a user interface, the thermostat configured to control the HVAC system in one or more of a steady-state condition, a programmed recovery condition, and a manual setpoint change condition, the method comprising:

maintaining in a memory of the thermostat at least one nominal droop value;

allowing modification of the at least one nominal droop value in the installer setup mode;

allowing a user to optionally invoking at least one override droop value to override the at least one nominal droop value via the user interface in the user mode;

the thermostat attempting to control the temperature of the inside space with the heat pump; and

in at least one of the programmed recovery condition and the manual setpoint change condition, the thermostat assessing whether adequate progress is being made toward a target temperature at a target time based at least in part on an appropriate one of the at least one nominal droop value and the at least one override droop value, and if adequate progress is not being made, activating the auxiliary heater.

20. The method of claim 19, wherein the at least one override droop value is selected via a qualitative scale.