DETECTING AND CORRECTING ENTHALPY WHEEL FAILURE MODES

• US 20130087302A1
• Filed: 10/06/2011
• Published: 04/11/2013
• Est. Priority Date: 10/06/2011
• Status: Active Grant

• Current Assignee: Lennox Industries Incorporated (Lennox International Incorporated)
• Original Assignee: Lennox Industries Incorporated (Lennox International Incorporated)
• Inventors: Perez, Eric, Schneider, Steve, Thomas, Greg, McKie, Justin
• Granted Patent: US 9,404,668 B2
• Time in Patent Office: Days
• US Class Current: 165/8
• 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 11/62 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 11/77 by controlling the speed of ventilators
• CPC Class Codes: F24F 11/81 by controlling the air supply to heat-exchangers or bypass channels
• CPC Class Codes: F24F 12/006 using an air-to-air heat exchanger F24F12/002 takes precedence
• CPC Class Codes: F24F 2110/40 Pressure, e.g. wind pressure
• CPC Class Codes: F24F 2140/00 Control inputs relating to system states
• CPC Class Codes: F24F 2203/10 Rotary wheel
• CPC Class Codes: F24F 2203/104 Heat exchanger wheel
• CPC Class Codes: F28D 19/041 with axial flow through the intermediate heat-transfer medium
• CPC Class Codes: F28F 27/006 specially adapted for regenerative heat-exchange apparatus
• CPC Class Codes: Y02B 30/56 Heat recovery units
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
• CPC Class Codes: Y10T 29/4935 Heat exchanger or boiler making

Abstract

A heating ventilation and cooling system includes an energy recovery ventilator (ERV). The ERV is configured to produce an inlet airstream and an exhaust airstream. An enthalpy wheel within the energy recovery ventilator is operable to transport heat between the inlet and exhaust airstreams. A pressure transducer is configured to determine a backpressure across the enthalpy wheel. A controller is configured to determine, in response to the backpressure, an operational characteristic of the enthalpy wheel.

Claims

1. A heating ventilation and cooling system, comprising:

an energy recovery ventilator configured to produce an inlet airstream and an exhaust airstream;

an enthalpy wheel within said energy recovery ventilator operable to transport heat between said inlet and exhaust airstreams;

a pressure transducer configured to determine a backpressure across said enthalpy wheel; and

a controller configured to determine, in response to said backpressure, an operational characteristic of said enthalpy wheel.

2. The system as recited in claim 1, wherein said operational characteristic is selected from the group consisting of:

a frosted condition;

a dirty condition; and

a disabled condition.

3. The system as recited in claim 1, wherein said controller is further configured to determine from said backpressure an airflow rate through said enthalpy wheel.

4. The system as recited in claim 1, wherein said enthalpy wheel is one of two enthalpy wheels within said energy recovery ventilator, and said controller is configured to determine that one of said enthalpy wheels is disabled.

5. The system as recited in claim 1, further comprising a conditioning unit coupled to said energy recovery ventilator, said unit configured to receive said inlet airstream from said energy recovery ventilator.

6. The system as recited in claim 4, wherein said controller is further configured to operate said system with reduced airflow in the event that one of said enthalpy wheels is inoperable.

7. The system as recited in claim 4, wherein said controller is further configured to communicate an alarm condition in the event that one of said enthalpy wheels is inoperable.

8. A method of controlling a heating, ventilating and air conditioning system, comprising:

measuring an air pressure within an energy recovery ventilator;

determining in response to said air pressure an operational characteristic of an enthalpy wheel located within said energy recovery ventilator.

9. The method as recited in claim 8, wherein said operational characteristic is selected from the group consisting of:

a frosted condition;

a dirty condition; and

a disabled condition.

10. The method as recited in claim 8, wherein said air pressure is measured between said enthalpy wheel and an economizer configured to receive an airstream from said energy recovery ventilator.

11. The method as recited in claim 9, further comprising controlling airflow within said energy recovery ventilator to correct said frosted condition or said dirty condition.

12. The method as recited in claim 9, further comprising continuing to operate said energy recovery ventilator with reduced airflow when said operational characteristic is a disabled state of said enthalpy wheel.

13. The method as recited in claim 8, wherein said enthalpy wheel is one of a plurality of enthalpy wheels within said energy recovery ventilator, and said method includes determining an operational characteristic of each of said enthalpy wheels.

14. A method of manufacturing a heating ventilation and cooling system, comprising:

configuring first and second blowers of an energy recovery ventilator to produce an inlet airstream and an exhaust airstream;

locating an enthalpy wheel within said energy recovery ventilator, said enthalpy wheel being operable to transport heat between said inlet and exhaust airstreams;

configuring a pressure transducer to determine a backpressure across said enthalpy wheel; and

configuring a controller to determine, in response to said backpressure, an operational characteristic of said enthalpy wheel.

15. The method as recited in claim 14, wherein said operational characteristic is selected from the group consisting of:

a frosted condition;

a dirty condition; and

a disabled condition.

16. The method as recited in claim 14, further comprising configuring said controller to determine from said backpressure an airflow rate through said enthalpy wheel.

17. The method as recited in claim 14, wherein said enthalpy wheel is one of two enthalpy wheels within said energy recovery ventilator, and further comprising configuring said controller to determine that one of said enthalpy wheels is disabled.

18. The method as recited in claim 14, further comprising coupling said energy recovery ventilator to a conditioning unit configured to receive said inlet airstream from said energy recovery ventilator.

19. The method as recited in claim 17, further comprising configuring said controller to operate said system with reduced airflow in the event that one of said enthalpy wheels is inoperable.

20. The method as recited in claim 17, further comprising configuring said controller to communicate an alarm condition in the event that one of said enthalpy wheels is inoperable.