Method of determining indoor or outdoor temperature limits

• US 7,024,283 B2
• Filed: 10/28/2002
• Issued: 04/04/2006
• Est. Priority Date: 10/28/2002
• Status: Active Grant

• Current Assignee: Trane International Inc. (Trane Technologies plc)
• Original Assignee: American Standard International Inc (Trane Technologies plc)
• Inventors: Bicknell, Kirby N.
• Primary Examiner(s): Gandhi, Jayprakash N.
• Application Number:
  US10/283,398
• Publication Number:
  US 20040083029A1
• Time in Patent Office: 1,254 Days
• Field of Search: 700/90, 700/275, 700/276, 165/200, 702/99, 236/10, 621/32
• US Class Current: 700/276
• CPC Class Codes: G05D 23/1931 to control the temperature of one space

Abstract

A method identifies at what outdoor temperature a heating or cooling system will need to operate at full capacity (e.g., 100% duty cycle) to maintain a desired indoor temperature. The tolerable outdoor temperature limit is identified by extrapolating data collected upon sampling the system'"'"'s performance (e.g., duty cycle) at various loads (e.g., difference between outdoor temperature and the indoor temperature). In a similar manner, the method can also predict a best achievable indoor temperature for a given outdoor temperature. The tolerable outdoor temperature limit and best achievable indoor temperature can be displayed to indicate whether the system needs servicing.

Claims

1. A method of determining a tolerable outdoor temperature limit for a temperature conditioning apparatus having a capacity that varies up to a maximum capacity, comprising:

determining a target indoor temperature;

sensing an outdoor temperature;

sensing an actual indoor temperature;

repeatedly comparing the outdoor temperature to at least one of the actual indoor temperature and the target indoor temperature to determine a plurality of load values;

varying the capacity of the temperature conditioning apparatus to help maintain the actual indoor temperature within a predetermined range of the target indoor temperature;

creating performance data by comparing the capacity to the plurality of load values; and

extrapolating the performance data to the maximum capacity to predict the tolerable outdoor temperature limit at which the temperature conditioning apparatus is expected to be able to maintain the actual indoor temperature within the predetermined range of the target indoor temperature.

2. The method of claim 1, wherein the step of varying the capacity is performed by cycling the temperature conditioning apparatus on and off to create a plurality of on-times and plurality of off-times.

3. The method of claim 2, further comprising determining a plurality of duty cycles of the temperature conditioning apparatus by comparing the plurality of on-times to the plurality of off-times.

4. The method of claim 3, wherein the step of creating performance data is performed by comparing the plurality of duty cycles to the plurality of load values.

5. The method of claim 1, wherein the temperature conditioning apparatus is a cooling apparatus.

6. The method of claim 1, wherein the temperature conditioning apparatus is a heating apparatus.

7. The method of claim 1, further comprising fitting a straight line through the performance data.

8. The method of claim 1, further comprising fitting a curved line through the performance data.

9. The method of claim 1, further comprising:

establishing a specified temperature limit; and

comparing the tolerable outdoor temperature limit to the specified temperature limit, thereby creating a comparison.

10. The method of claim 6, displaying a signal that reflects the comparison.

11. The method of claim 10, wherein the signal indicates that the temperature conditioning apparatus may need servicing.

12. The method of claim 1, further comprising displaying the tolerable outdoor temperature limit.

13. The method of claim 1, further comprising predicting a best achievable indoor temperature based on the performance data and the outdoor temperature.

14. The method of claim 13, further comprising displaying the best achievable indoor temperature.

15. A method of determining a tolerable outdoor temperature limit for a temperature conditioning apparatus, comprising:

determining a target indoor temperature;

sensing an outdoor temperature;

sensing an actual indoor temperature;

repeatedly comparing the outdoor temperature to at least one of the actual indoor temperature and the target indoor temperature to determine a plurality of load values;

cycling the temperature conditioning apparatus on and off to create a plurality of on-times and plurality of off-times, whereby cycling the temperature conditioning apparatus helps maintain the actual indoor temperature within a predetermined range of the target indoor temperature;

determining a plurality of duty cycles of the temperature conditioning apparatus by comparing the plurality of on-times to the plurality of off-times;

creating performance data by comparing the plurality of duty cycles to the plurality of load values; and

extrapolating the performance data to predict the tolerable outdoor temperature limit at which the temperature conditioning apparatus is expected to be able to maintain the actual indoor temperature within the predetermined range of the target indoor temperature.

16. The method of claim 15, wherein the temperature conditioning apparatus is a cooling apparatus.

17. The method of claim 15, wherein the temperature conditioning apparatus is a heating apparatus.

18. The method of claim 15, further comprising fitting a straight line through the performance data.

19. The method of claim 15, further comprising fitting a curved line through the performance data.

20. The method of claim 15, further comprising:

establishing a specified temperature limit; and

comparing the tolerable outdoor temperature limit to the specified temperature limit, thereby creating a comparison.

21. The method of claim 20, displaying a signal that reflects the comparison.

22. The method of claim 21, wherein the signal indicates that the temperature conditioning apparatus may need servicing.

23. The method of claim 15, further comprising displaying the tolerable outdoor temperature limit.

24. The method of claim 15, further comprising predicting a best achievable indoor temperature based on the performance data and the outdoor temperature.

25. The method of claim 24, further comprising displaying the best achievable indoor temperature.

26. A method of determining a tolerable outdoor temperature limit for a temperature conditioning apparatus, comprising:

determining a target indoor temperature;

sensing an outdoor temperature;

sensing an actual indoor temperature;

repeatedly comparing the outdoor temperature to at least one of the actual indoor temperature and the target indoor temperature to determine a plurality of load values;

cycling the temperature conditioning apparatus on and off to create a plurality of on-times and plurality of off-times, whereby cycling the temperature conditioning apparatus helps maintain the actual indoor temperature within a predetermined range of the target indoor temperature;

determining a plurality of duty cycles of the temperature conditioning apparatus by comparing the plurality of on-times to the plurality of off-times;

creating performance data by comparing the plurality of duty cycles to the plurality of load values;

based on the performance data, predicting the tolerable outdoor temperature limit at which the temperature conditioning apparatus is expected to be able to maintain the indoor temperature within the predetermined range of the target indoor temperature;

establishing a specified temperature limit;

comparing the tolerable outdoor temperature limit to the specified temperature limit, thereby creating a comparison; and

displaying a signal that reflects the comparison.

27. The method of claim 26, wherein the temperature conditioning apparatus is a cooling apparatus.

28. The method of claim 26, wherein the temperature conditioning apparatus is a heating apparatus.

29. The method of claim 26, further comprising fitting a straight line through the performance data.

30. The method of claim 26, further comprising fitting a curved line through the performance data.

31. The method of claim 26, wherein the signal indicates that the temperature conditioning apparatus may need servicing.

32. The method of claim 26, further comprising displaying the tolerable outdoor temperature limit.

33. The method of claim 26, further comprising predicting a best achievable indoor temperature based on the performance data and the outdoor temperature.

34. The method of claim 33, further comprising displaying the best achievable indoor temperature.

35. A method of determining a tolerable outdoor temperature limit for a temperature conditioning apparatus, comprising:

determining a target indoor temperature;

sensing an outdoor temperature;

sensing an actual indoor temperature;

repeatedly comparing the outdoor temperature to at least one of the actual indoor temperature and the target indoor temperature to determine a plurality of load values;

cycling the temperature conditioning apparatus on and off to create a plurality of on-times and plurality of off-times, whereby cycling the temperature conditioning apparatus helps maintain the actual indoor temperature within a predetermined range of the target indoor temperature;

determining a plurality of duty cycles of the temperature conditioning apparatus by comparing the plurality of on-times to the plurality of off-times;

creating performance data by comparing the plurality of duty cycles to the plurality of load values;

fitting a line through the performance data;

extrapolating the performance data via the line to predict the tolerable outdoor temperature limit at which the temperature conditioning apparatus is expected to be able to maintain the actual indoor temperature within the predetermined range of the target indoor temperature;

establishing a specified temperature limit;

comparing the tolerable outdoor temperature limit to the specified temperature limit, thereby creating a comparison; and

displaying a signal that reflects the comparison, wherein the signal indicates that the temperature conditioning apparatus may need servicing.

36. The method of claim 35, wherein the temperature conditioning apparatus is a cooling apparatus.

37. The method of claim 35, wherein the temperature conditioning apparatus is a heating apparatus.

38. The method of claim 35, wherein the line is a straight line.

39. The method of claim 35, wherein the line is a curved line.

40. The method of claim 35, further comprising displaying the tolerable outdoor temperature limit.

41. The method of claim 35, further comprising predicting a best achievable indoor temperature based on the performance data and the outdoor temperature.

42. The method of claim 41, further comprising displaying the best achievable indoor temperature.

43. A method of determining a tolerable outdoor limit for a conditioning apparatus having a capacity that varies up to a maximum capacity, comprising:

determining a target indoor condition;

sensing an outdoor condition;

sensing an actual indoor condition;

repeatedly comparing the outdoor condition to at least one of the actual indoor condition and the target indoor condition to determine a plurality of load values;

varying the capacity of the conditioning apparatus to help maintain the actual indoor condition within a predetermined range of the target indoor condition;

creating performance data by comparing the capacity to the plurality of load values; and

extrapolating the performance data to the maximum capacity to predict the tolerable outdoor condition limit at which the conditioning apparatus is expected to be able to maintain the actual indoor condition within the predetermined range of the target indoor condition.

44. The method of claim 43, wherein the step of varying the capacity is performed by cycling the conditioning apparatus on and off to create a plurality of on-times and plurality of off-times.

45. The method of claim 44, further comprising determining a plurality of duty cycles of the conditioning apparatus by comparing the plurality of on-times to the plurality of off-times.

46. The method of claim 45, wherein the step of creating performance data is performed by comparing the plurality of duty cycles to the plurality of load values.

47. The method of claim 43, wherein the conditioning apparatus is a temperature cooling apparatus.

48. The method of claim 43, wherein the conditioning apparatus is a temperature heating apparatus.

49. A temperature conditioning apparatus having a capacity that varies up to a maximum capacity, comprising:

means for determining a target indoor temperature;

means for sensing an outdoor temperature;

means for sensing an actual indoor temperature;

means for repeatedly comparing the outdoor temperature to at least one of the actual indoor temperature and the target indoor temperature to determine a plurality of load values;

means for varying the capacity of the temperature conditioning apparatus to help maintain the actual indoor temperature within a predetermined range of the target indoor temperature;

means for creating performance data by comparing the capacity to the plurality of load values; and

means for extrapolating the performance data to the maximum capacity to predict the tolerable outdoor temperature limit at which the temperature conditioning apparatus is expected to be able to maintain the actual indoor temperature within the predetermined range of the target indoor temperature.

50. The apparatus of claim 49, wherein the step of varying the capacity further includes means for cycling the temperature conditioning apparatus on and off to create a plurality of on-times and plurality of off-times.

51. The apparatus of claim 50, further comprising means for determining a plurality of duty cycles of the temperature conditioning apparatus by comparing the plurality of on-times to the plurality of off-times.

52. The apparatus of claim 51, wherein the step of creating performance data includes means for comparing the plurality of duty cycles to the plurality of load values.

53. The apparatus of claim 49, further comprising:

means for establishing a specified temperature limit; and

means for comparing the tolerable outdoor temperature limit to the specified temperature limit, thereby creating a comparison.

54. A temperature conditioning apparatus, comprising:

means for determining a target indoor temperature;

means for sensing an outdoor temperature;

means for sensing an actual indoor temperature;

means for repeatedly comparing the outdoor temperature to at least one of the actual indoor temperature and the target indoor temperature to determine a plurality of load values;

means for cycling the temperature conditioning apparatus on and off to create a plurality of on-times and plurality of off-times, whereby cycling the temperature conditioning apparatus helps maintain the actual indoor temperature within a predetermined range of the target indoor temperature;

means for determining a plurality of duty cycles of the temperature conditioning apparatus by comparing the plurality of on-times to the plurality of off-times;

means for creating performance data by comparing the plurality of duty cycles to the plurality of load values; and

means for extrapolating the performance data to predict the tolerable outdoor temperature limit at which the temperature conditioning apparatus is expected to be able to maintain the actual indoor temperature within the predetermined range of the target indoor temperature.

55. The apparatus of claim 54, further comprising:

means for establishing a specified temperature limit; and

means for comparing the tolerable outdoor temperature limit to the specified temperature limit, thereby creating a comparison.

56. The apparatus of claim 55 further including means for, displaying a signal that reflects the comparison.

57. The apparatus of claim 56, wherein the signal indicates that the temperature conditioning apparatus may need servicing.

58. The apparatus of claim 54, further comprising means for displaying the tolerable outdoor temperature limit.

59. The apparatus of claim 54, further comprising means for predicting a best achievable indoor temperature based on the performance data and the outdoor temperature.