BACKUP CONTROL FOR HVAC SYSTEM

• US 20100006660A1
• Filed: 07/10/2008
• Published: 01/14/2010
• Est. Priority Date: 07/10/2008
• Status: Active Grant

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Grenkoski, James, Leen, Cary, Frint, Jiri, Bergman, Gabriel A.
• Granted Patent: US 7,992,794 B2
• Time in Patent Office: Days
• US Class Current: 236/51
• 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 11/32 Responding to malfunctions or emergencies
• CPC Class Codes: F24F 11/38 Failure diagnosis
• CPC Class Codes: F24F 11/56 Remote control
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 11/77 by controlling the speed of ventilators
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: G05D 23/1931 to control the temperature of one space

Abstract

An equipment interface module that can operate one or more pieces of HVAC equipment in accordance with instructions received from a properly operating thermostat, yet can also operate the HVAC equipment when communications between the thermostat and the HVAC controller are lost due to, for example, low battery power at the thermostat, malfunctioning thermostat sensor(s), malfunctioning communication and/or thermostat circuitry, electrical interference, and the like. In some instances, the equipment interface module may regulate the HVAC equipment in accordance with a signal from a remote sensor when communication with the thermostat is lost.

Claims

1. An HVAC system comprising:

an HVAC component having an HVAC controller;

a remotely located wireless thermostat; and

an equipment interface module in communication with the wireless thermostat, the equipment interface module configured to provide instructions to the HVAC controller in response to signals received from the wireless thermostat;

wherein the equipment interface module is also configured to provide instructions to the HVAC controller without input from the thermostat if/when the equipment interface module loses communication with the wireless thermostat.

2. The HVAC system of claim 1, further comprising a remote sensor that is in communication with the equipment interface module, the remote sensor providing the equipment interface module with a control signal related to an environmental parameter within a building.

3. The HVAC system of claim 2, wherein the HVAC component comprises a forced air HVAC unit having a circulating blower, and the equipment interface module is configured to activate the circulating blower in order to move air past the remote sensor when the equipment interface module loses communication with the wireless thermostat.

4. The HVAC system of claim 3, wherein the equipment interface module operates the circulating blower continuously until communication is restored between the equipment interface module and the wireless thermostat.

5. The HVAC system of claim 1, wherein the equipment interface module operates the HVAC component in accordance with a predetermined temperature setpoint when communication is lost between the equipment interface module and the wireless thermostat.

6. The HVAC system of claim 1, wherein the wireless thermostat comprises a battery, and communication between the equipment interface module and the wireless thermostat is lost as a result of the battery having insufficient energy to operate the wireless thermostat.

7. The HVAC system of claim 1, wherein the wireless thermostat comprises an RF transmitter and the equipment interface module comprises an RF receiver.

8. The HVAC system of claim 1, wherein the forced air HVAC unit comprises a furnace.

9. The HVAC system of claim 1, wherein the forced air HVAC unit comprises an air conditioner.

10. The HVAC system of claim 2, wherein the remote sensor comprises a return air temperature sensor.

11. The HVAC system of claim 2, wherein the remote sensor comprises a temperature sensor disposed within a thermostat remote control.

12. The HVAC system of claim 2, wherein the remote sensor comprises an outdoor air sensor.

13. The HVAC system of claim 2, wherein the remote sensor comprises a humidity sensor and the equipment interface module is configured to operate the HVAC component to limit a humidity level when communication is lost between the equipment interface module and the wireless thermostat.

14. The HVAC system of claim 1, wherein the equipment interface module is configured to remember equipment configuration information previously provided by the wireless thermostat.

15. The HVAC system of claim 14, wherein the equipment interface module is configured to provide instructions to the HVAC controller, in the absence of communication with the wireless thermostat, in accordance with the remembered equipment configuration.

16. A method of operating an HVAC system comprising an HVAC component and an HVAC controller, a wireless thermostat, a equipment interface module exterior to the HVAC component and a remote sensor, the method comprising the steps of:

operating the HVAC component in accordance with instructions received from the wireless thermostat;

detecting if communication between the wireless thermostat and the equipment interface module fails; and

controlling the HVAC component via the equipment interface module and the remote sensor until communication between the wireless thermostat and the equipment interface module is reestablished.

17. The method of claim 16, wherein controlling the HVAC component via the equipment interface module and the remote sensor comprises detecting an environmental parameter using the remote sensor, and controlling the HVAC component in accordance with a predetermined value of the environmental parameter.

18. The method of claim 17, wherein the HVAC component comprises a forced air HVAC unit having a blower and the environmental parameter comprises a return air temperature, and controlling the HVAC component via the equipment interface module and the remote sensor comprises:

operating the blower continuously;

monitoring the return air temperature; and

controlling the HVAC component to achieve a desired return air temperature.

19. An equipment interface module configured to communicate with a wireless thermostat and a remote sensor, the equipment interface module configured to provide instructions to an HVAC component including a circulating blower, the equipment interface module comprising:

an RF receiver; and

a controller that is configured to

recognize if/when communication between the wireless thermostat and the equipment module is lost;

start the circulating blower when communication is lost; and

operate the HVAC component in accordance with a signal from the remote sensor until communication between the wireless thermostat and the equipment module is restored.

20. The equipment interface module of claim 19, wherein the remote sensor comprises a return air temperature, the controller configured to:

operate the blower continuously;

monitor the return air temperature; and

control the HVAC component to achieve a desired return air temperature.