Diagnostic system

1. A compressor comprising a shell, a compression mechanism, a motor, and a diagnostic system for determining non-severe fault conditions where continued operation of the compressor is permitted by said diagnostic system and severe fault conditions where operation of the compressor is stopped by said diagnostic system, said diagnostic system including a processor and a memory and operable to predict said severe fault conditions before occurrence of said severe fault conditions based on an order of a sequence of historical fault events and a combination of the types of said historical fault events, said historical fault events being determined based on compressor run time and at least one of a state of a motor protector, a low-pressure cutout switch, and a high-pressure cutout switch.

2. The compressor of claim 1 , further comprising a current sensor in communication with said processor.

3. The compressor of claim 2 , wherein said processor determines a state of at least one of said low-pressure cutout switch, said high-pressure cutout switch, and said motor protector based on information received from said current sensor and compressor ON times and OFF times.

4. The compressor of claim 1 , further comprising at least one of an ambient-temperature sensor, a discharge-temperature switch, and a pressure-relief valve.

5. The compressor of claim 1 , further comprising a discharge-temperature switch, wherein said processor determines severity of a low-side system condition based on at least one of an order sequence and a combination of: compressor run time, opening of said low-pressure cutout switch, motor-protector trips, and trips of said discharge-temperature-switch.

6. The compressor of claim 5 , wherein said discharge-temperature-switch trips are detected based on a predetermined decrease of compressor current.

7. The compressor of claim 6 , wherein said predetermined decrease is approximately twenty percent (20%) to thirty percent (30%) within a period of approximately two (2) to five (5) seconds.

8. The compressor of claim 1 , further comprising a pressure-relief valve, wherein said processor determines severity of a high-side system condition based on at least one of a sequence or combination of: opening of said high-pressure cutout switch, motor-protector trips, and trips of said pressure-relief-valve.

9. The compressor of claim 8 , wherein said pressure-relief-valve trips are detected based on a predetermined decrease of compressor current.

10. The compressor of claim 9 , wherein said predetermined decrease is approximately twenty percent (20%) to thirty percent (30%) within a period of approximately two (2) to five (5) seconds.

11. The compressor of claim 1 , wherein said processor determines the rate of progression over time of said types of historical fault events within said order sequence or combination.

12. The compressor of claim 1 , wherein said diagnostic system differentiates between said non-severe fault conditions and said severe fault conditions based on said sequence or combination of historical fault events all recurring within a predetermined time period.

13. The compressor of claim 12 , wherein said predetermined time period is one of a week, a month, a summer season, or a winter season.

14. The compressor of claim 8 , wherein said motor-protector trips are detected after opening of the pressure relief valve for a period of time.

15. The compressor of claim 14 , wherein said period of time is approximately fifteen (15) minutes.

16. A compressor comprising a shell, a compression mechanism, a motor, and a diagnostic system for determining a system condition, said diagnostic system including a processor and a memory and operable to determine non-severe fault conditions where continued operation of the compressor is permitted by said diagnostic system and severe fault conditions where operation of the compressor is stopped by said diagnostic system, said diagnostic system operable to predict said severe fault conditions before occurrence of said severe fault conditions based on an order of a sequence of historical fault events that are determined based on compressor run time and at least one of a state of a motor protector, a low-pressure cutout switch, and a high-pressure cutout switch and the rate of progression over time of said historical fault events within an order sequence of said historical fault events.

17. The compressor of claim 16 , further comprising a current sensor in communication with said processor.

18. The compressor of claim 16 , wherein said processor determines a state of at least one of said low-pressure cutout switch, said high-pressure cutout switch, and said motor protector based on information received from said current sensor and compressor ON times and OFF times.

19. The compressor of claim 16 , further comprising at least one of an ambient-temperature sensor, a discharge-temperature switch, and a pressure-relief valve.

20. The compressor of claim 16 , further comprising a discharge-temperature switch, wherein said processor determines severity of a low-side system condition based on at least one of an order sequence and a combination of: compressor run time, opening of said low-pressure cutout switch, motor-protector trips, and trips of said discharge-temperature-switch.

21. The compressor of claim 20 , wherein said discharge-temperature-switch trips are detected based on a predetermined decrease of compressor current.

22. The compressor of claim 21 , wherein said predetermined decrease is approximately twenty percent (20%) to thirty percent (30%) within a period of approximately two (2) to five (5) seconds.

23. The compressor of claim 16 , further comprising a pressure-relief valve, wherein said processor determines severity of a high-side system condition based on at least one of a sequence or combination of: opening of said high-pressure cutout switch, motor-protector trips, and trips of said pressure-relief-valve.

24. The compressor of claim 23 , wherein said pressure-relief-valve trips are detected based on a predetermined decrease of compressor current.

25. The compressor of claim 24 , wherein said predetermined decrease is approximately twenty percent (20%) to thirty percent (30%) within a period of approximately two (2) to five (5) seconds.

26. The compressor of claim 16 , wherein said diagnostic system differentiates between said non-severe fault conditions and said severe fault conditions based on a sequence of historical fault events all recurring within a predetermined time period.

27. The compressor of claim 26 , wherein said predetermined time period is one of a week, a month, a summer season, or a winter season.

28. The compressor of claim 25 , wherein said motor-protector trips are detected after opening of the high-pressure relief valve for a period of time.

29. The compressor of claim 28 , wherein said period of time is approximately fifteen (15) minutes.