Time based cooling below set point temperature

• US 4,850,198 A
• Filed: 01/17/1989
• Issued: 07/25/1989
• Est. Priority Date: 01/17/1989
• Status: Expired due to Term

• Current Assignee: Trane International Inc. (Trane Technologies plc)
• Original Assignee: American Standard Inc. (Trane Technologies plc)
• Inventors: Neal, John D., Helt, Robert W.
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US07/297,920
• Time in Patent Office: 189 Days
• Field of Search: 236/46 R, 62/157, 62/231, 62/173, 62/93, 165/12
• US Class Current: 62/93
• 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 11/64 using pre-stored data
• CPC Class Codes: F24F 11/86 by controlling compressors within refrigeration or heat pump circuits
• CPC Class Codes: F25B 2600/0251 with on-off operation
• CPC Class Codes: F25B 2600/0253 with variable speed
• CPC Class Codes: F25B 2700/2104 of an indoor room or compartment
• CPC Class Codes: F25B 49/022 Compressor control arrangements
• CPC Class Codes: G05D 23/1917 using digital means
• CPC Class Codes: G05D 23/20 with sensing elements having variation of electric or magnetic properties with change of temperature G05D23/13 takes precedence
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A method of controlling a refrigeration compressor involves momentarily energizing the compressor after extended off periods. When the temperature of a comfort zone remains below its set point temperature for an extended period, such as at night, periodically energizing the compressor for brief periods improves the confort level of the zone.

Claims

1. A method of controlling a cooling apparatus comprising the steps of:

sensing a zone temperature of a comfort zone;

energizing a refrigeration compressor to affect cooling of said zone when said zone temperature is generally above a set point temperature;

de-energizing said compressor when said zone temperature drops generally below a first predetermined temperature limit; and

relying on a timer in re-energizing said compressor to affect further cooling of said zone for a first predetermined on-period when said zone temperature remains below said set point temperature and above a second predetermined temperature limit for a first predetermined off-period.

2. The method as recited in claim 1, wherein said compressor is of variable speed and in the step of energizing, said compressor is driven at speeds that are most often higher than those when said compressor is driven during the step of re-energizing.

3. The method as recited in claim 1, further comprising the step of prohibiting the re-energizing to affect cooling of said zone when said zone temperature is below said second predetermined temperature limit.

4. The method as recited in claim 1, further comprising the step of relying on said timer for re-energizing said compressor to affect further cooling of said zone for a second predetermined on-period when said zone temperature remains below said second predetermined temperature limit and above a third predetermined temperature limit for a second predetermined off-period, with said second predetermined off-period being longer than said first predetermined off-period.

5. The method as recited in claim 4, further comprising the step of prohibiting the re-energizing to affect cooling of said zone when said zone temperature is below said third predetermined temperature limit.

6. A method of controlling a cooling apparatus comprising the steps of:

sensing a zone temperature of a comfort zone;

energizing a refrigeration compressor to affect cooling of said zone when said zone temperature is generally above a set point temperature;

de-energizing said compressor when said zone temperature drops below a first predetermined temperature limit;

storing a digital value representing said zone temperature that existed just as said compressor changed between an energized state and a de-energized state; and

re-energizing said compressor for a first predetermined on-period when,

i. said zone temperature remains below said digital value and above a second predetermined temperature limit for a first predetermined off-period, and

ii. a temperature difference between said zone temperature and said digital value remains within a predetermined number of degrees.

7. The method as recited in claim 6, wherein said digital value represents said zone temperature that existed just as said compressor was last de-energized due to said zone temperature dropping below said first predetermined temperature limit.

8. The method as recited in claim 6, wherein said digital value represents said zone temperature that existed just as said compressor was last energized due to said zone temperature rising above said set point temperature.

9. The method as recited in claim 6, wherein said compressor is of variable speed and in the step of energizing, said compressor is driven at speeds that are most often higher than those when said compressor is driven during the step of re-energizing.

10. The method as recited in claim 6, further comprising the step of prohibiting the re-energizing to affect cooling of said zone when said zone temperature is below said second predetermined temperature limit.

11. The method as recited in claim 6, further comprising the step of relying on said timer for re-energizing said compressor to affect further cooling of said zone for a second predetermined on-period when said zone temperature remains below said second predetermined temperature limit and above a third predetermined temperature limit for a second predetermined off-period, with said second predetermined off-period being longer than said first predetermined off-period.

12. The method as recited in claim 11, further comprising the step of prohibiting the re-energizing to affect cooling of said zone when said zone temperature is below said third predetermined temperature limit.

13. A method of controlling a cooling apparatus having a variable speed compressor and a supply air fan blowing across an evaporator, said method comprising the steps of:

sensing a zone temperature of a comfort zone;

energizing said refrigeration compressor and said supply air fan to affect cooling of said zone when said zone temperature is generally above a set point temperature;

de-energizing said compressor and said fan when said zone temperature drops generally below a first predetermined temperature limit;

relying on a timer in re-energizing said compressor and said fan to affect further cooling of said zone for a first predetermined on-period when said zone temperature remains generally below said set point temperature and above a second predetermined temperature limit for a first predetermined off-period;

relying on said timer for re-energizing said compressor and said fan to effect further cooling of said zone for a second predetermined on-period when said zone temperature remains below said second predetermined temperature limit and above a third predetermined temperature limit for a second predetermined off-period, with said second predetermined off-period being longer than said first predetermined off-period; and

prohibiting the re-.energizing of said compressor and said fan to affect cooling of said zone when said zone temperature is below said third predetermined temperature limit.

14. The method as recited in claim 13, wherein the step of energizing, said compressor is driven at speeds that are generally higher than those when said compressor is driven during the steps of re-energizing.