HVAC remote monitoring system

• US 6,385,510 B1
• Filed: 12/02/1998
• Issued: 05/07/2002
• Est. Priority Date: 12/03/1997
• Status: Expired due to Fees

• Current Assignee: Klaus D. Hoog, Nims P. Knobloch Jr
• Original Assignee: Klaus D. Hoog, Nims P. Knobloch Jr
• Inventors: Knobloch, Nims P. Jr., Hoog, Klaus D.
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): Hartman, Jr., Ronald D
• Application Number:
  US09/203,728
• Time in Patent Office: 1,252 Days
• Field of Search: 700/276, 700/278, 700/108, 379/102.05
• US Class Current: 700/276
• 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 11/38 Failure diagnosis
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/57 using telephone networks
• CPC Class Codes: F24F 11/58 using Internet communication

Abstract

An electronic HVAC monitoring computer continuously monitors the general condition and efficiency of an HVAC system and notifies a central station computer via modem link or other signal transmission means, when the general condition or efficiency of the HVAC system falls below certain industry standard values by a pre-set amount.

Claims

1. An apparatus for monitoring the performance of an HVAC unit having a heating mode and a cooling mode operation, said apparatus comprising:

means for continuously monitoring air temperature and air humidity, the means for monitoring positioned to sense a real-time value for a supply air temperature, a return air temperature and a return air relative humidity for the HVAC unit, and responsively generating data outputs for said supply air temperature, said return air temperature and said return air relative humidity;

a monitor processing unit constructed and arranged to receive said data outputs for the real-time values for both return air temperature and return air relative humidity in addition to supply air temperature during a selected one of the heating mode and cooling mode operations and responsively establishing a corresponding correction factor, said correction factor representing a difference between a theoretical ideal performance operation of said HVAC unit and a best actual performance operation of said HVAC unit, and responsively establishing an adjustable operating range based on said correction factor; and

means for inputting data defining a selected operating range for the HVAC unit encompassing the adjustable operating range;

said monitor processing unit being constructed and arranged to output a performance result of said HVAC unit when said HVAC unit operates outside the selected operating range.

2. The apparatus according to claim 1, wherein said means for inputting data comprises an input device connected to the monitor processing unit for entering input data, the input data comprising said supply air temperature, return air temperature and return air humidity of the HVAC unit under the theoretical ideal performance operation.

3. The apparatus according to claim 1, further comprising a means for transmitting said performance result to a remote location.

4. The apparatus according to claim 2, wherein said monitor processing unit responsively establishes said best actual performance operation of the HVAC unit from the data outputs of said supply air temperature, return air temperature and return air relative humidity when the HVAC unit is operating under best practicable conditions.

5. The apparatus according to claim 1, wherein the heating mode correction factor is a temperature value equal to the difference between a theoretical ideal temperature differential and a best actual temperature differential for a given return air temperature reading measured, respectively, by the supply air temperature and the return air temperature during the theoretical ideal performance operation of the HVAC unit and the best actual performance operation of the HVAC unit.

9. The apparatus according to claim 1, wherein the cooling mode correction factor is a temperature value equal to the difference between a theoretical ideal temperature differential and a best actual temperature differential for a given return air temperature and relative humidity reading measured, respectively, by the supply air temperature and the return air temperature during the theoretical ideal performance operation of the HVAC unit and the best actual performance operation of the HVAC unit.

12. The apparatus according to claim 1, wherein the means for determining when the HVAC unit operates outside the selected operating range comprises a controller device which signals the monitor processing unit when said HVAC unit operates outside said selected operating range corresponding to the heating mode operation for a given return air temperature reading and corresponding to the cooling mode operation for a given return air temperature and relative humidity reading.

13. The apparatus according to claim 1, wherein the means for monitoring the supply air temperature comprises a supply air temperature probe proximate a supply air duct of said HVAC unit and the means for monitoring the return air temperature and return air relative humidity comprise, respectively, a return air temperature probe and a relative humidity probe proximate a return air duct of said HVAC unit, wherein said data outputs of said probes represent real-time analog readings of the air temperatures and relative humidity and said data outputs are converted from analog to digital form by an analog to digital converter.

14. The apparatus according to claim 3 wherein said means for transmitting a performance result of said HVAC unit comprises:

an alarm triggered by the monitor processing unit when the HVAC unit operates outside the selected operating mode established for the corresponding heating and cooling mode operations;

an HVAC telemeter connected to said alarm, telemetering the performance results, including identification and specification information for the HVAC unit; and

a remote central station computer for receiving the performance results and identification and specification information wherein a repair and maintenance recommendation is prepared.

15. The apparatus according to claim 14 wherein said remote central station computer further comprises:

a database of repair and maintenance information for a multiplicity of HVAC units; and

,

a remote station telemeter for transferring the performance results, identification and specification information, and said repair and maintenance recommendation to a HVAC contractor located near the HVAC unit.

16. The apparatus according to claim 14 wherein said HVAC telemeter comprises a computer modem connection between the monitor processing unit and the central station computer.

17. The apparatus according to claim 15 wherein said remote station telemeter comprises a facsimile connection between the central station computer and the HVAC contractor.

6. An apparatus for monitoring the performance of an HVAC unit having a heating mode and a cooling mode operation, said apparatus comprising:

means for monitoring air temperature and air humidity, the means for monitoring positioned to sense a value for a supply air temperature, a return air temperature and a return air relative humidity for the HVAC unit, and responsively generating data outputs for said supply air temperature, said return air temperature and said return air relative humidity;

a monitor processing unit constructed and arranged to receive said data outputs for the real-time values for both return air temperature and return air relative humidity in addition to supply air temperature during a selected one of the heating mode and cooling mode operations and responsively establishing a corresponding correction factor, said correction factor representing a difference between a theoretical ideal performance operation of said HVAC unit and a best actual performance operation of said HVAC unit, and responsively establishing an adjustable operating range based on said correction factor, wherein the heating mode correction factor is a temperature value equal to the difference between a theoretical ideal temperature differential and a best actual temperature differential for a given return air temperature reading measured, respectively, by the supply air temperature and the return air temperature during the theoretical ideal performance operation of the HVAC unit and the best actual performance operation of the HVAC unit; and

means for inputting data defining a selected operating range for the HVAC unit encompassing the adjustable operating range, wherein the adjustable operating range is a temperature differential greater than the theoretical ideal temperature differential minus the correction factor for said given return air temperature reading;

said monitor processing unit being constructed and arranged to output a performance result of said HVAC unit when said HVAC unit operates outside the selected operating range.

7. The apparatus according to claim 6, wherein the selected operating range is a temperature differential equal to or greater than said operating range.

8. An apparatus for monitoring the performance of an HVAC unit having a heating mode operation, said apparatus comprising:

means for continuously monitoring air temperature and air humidity, the means for monitoring positioned to sense a real-time value for a supply air temperature, a return air temperature and a return air relative humidity for the HVAC unit, and responsively generating data outputs for said supply air temperature, said return air temperature and said return air relative humidity;

a monitor processing unit constructed and arranged to receive said data outputs for the real-time values for both return air temperature and return air relative humidity in addition to supply air temperature during a selected one of the heating mode and cooling mode operations and responsively establishing a corresponding correction factor, said correction factor representing a difference between a theoretical ideal performance operation of said HVAC unit and a best actual performance operation of said HVAC unit, and responsively establishing an adjustable operating range based on said correction factor, wherein the heating mode correction factor is a temperature value equal to the difference between a theoretical ideal temperature differential and a best actual temperature differential for a given return air temperature reading measured, respectively, by the supply air temperature and the return air temperature during the theoretical ideal performance operation of the HVAC unit and the best actual performance operation of the HVAC unit, wherein the ideal temperature differential is calculated according to an equation selected from the group consisting of;

for heat generated by electric;

10. An apparatus for monitoring the performance of an HVAC unit having a cooling mode operation, said apparatus comprising:

means for monitoring air temperature and air humidity, the means for monitoring positioned to sense a value for a supply air temperature, a return air temperature and a return air relative humidity for the HVAC unit, and responsively generating data outputs for said supply air temperature, said return air temperature and said return air relative humidity;

a monitor processing unit constructed and arranged to receive said data outputs for the real-time values for both return air temperature and return air relative humidity in addition to supply air temperature during a selected one of the heating mode and cooling mode operations and responsively establishing a corresponding correction factor, said correction factor representing a difference between a theoretical ideal performance operation of said HVAC unit and a best actual performance operation of said HVAC unit, and responsively establishing an adjustable operating range based on said correction factor, wherein the cooling mode correction factor is a temperature value equal to the difference between a theoretical ideal temperature differential and a best actual temperature differential for a given return air temperature and relative humidity reading measured, respectively, by the supply air temperature and the return air temperature during the theoretical ideal performance operation of the HVAC unit and the best actual performance operation of the HVAC unit; and

means for inputting data defining a selected operating range for the HVAC unit encompassing the adjustable operating range, wherein the adjustable operating range is a temperature differential greater than the theoretical ideal temperature differential plus the correction factor for said given return air temperature and relative humidity; and

said monitor processing unit being constructed and arranged to output a performance result of said HVAC unit when said HVAC unit operates outside the selected operating range.

11. The apparatus according to claim 10, wherein the selected operating range is a temperature differential equal to or greater than said operating range.

18. An apparatus for monitoring the performance of an HVAC unit, comprising:

means for continuously monitoring a supply air temperature, a return air temperature and a return air relative humidity of the HVAC unit, said means for monitoring generating data outputs for said supply air temperature, said return air temperature and said return air relative humidity;

monitor processing unit having a microprocessor and a memory storage, said monitor processing unit linked to said means for monitoring to record and analyze said data outputs;

means for calibrating said monitor processing unit establishing an operating correction factor for said HVAC unit, said correction factor representing a difference between an ideal performance operation of said HVAC unit and an actual performance operation of said HVAC unit;

means for determining when said HVAC unit operates outside a desirable operating range;

a telemeter device for transmitting a performance result of said HVAC unit when it operates outside the selected operating range, said performance results comprising a periodic sampling of the supply air temperature, return air temperature and the return air relative humidity of the HVAC unit over a determined time period and an HVAC unit identification, specification and correction factor information for the HVAC unit; and

a remote central station computer for diagnosing the performance result of the HVAC unit when the HVAC unit operates outside the selected operating range.

19. The apparatus according to claim 18, wherein the monitor processing unit comprises a microprocessor having memory storage.

20. The apparatus according to claim 18, wherein the input device comprises a keyboard for entering said input data into the monitor processing unit.

21. A method for monitoring the performance of an HVAC unit, comprising the steps of:

monitoring continuously a supply air temperature, a return air temperature and a return air relative humidity of the HVAC unit;

transmitting a plurality of output readings generated from the monitoring of temperatures and relative humidity of the HVAC unit;

calibrating a monitor processing unit that receives the output readings from the monitoring of temperatures and relative humidity, wherein a comparison is made between an actual operating range and an pre-selected operating range of the HVAC unit during a heating and cooling mode operation;

triggering an alarm when the HVAC unit is operating outside said pre-selected operating range;

telemetering the output readings and HVAC unit specifications to a remote central computer; and

evaluating the output readings for determining recommended repairs and maintenance of the HVAC unit.

22. The method according to claim 21 wherein calibrating the monitor processing unit comprises the steps of:

inputting data comprising ideal input readings and best actual input readings of supply air temperature, return air temperature and relative humidity readings for the HVAC unit;

calculating a correction factor temperature differential under a heating mode operation and a cooling mode operation; and

setting a heating mode tolerance point temperature differential and a cooling mode tolerance point temperature differential based on a desired tolerance from the corresponding heating or cooling mode correction factor temperature differential.