US6679072B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diagnostic system and method for a cooling system
Assignee: Copeland LP
•
Filing: 2002-11-27
•
Granted: 2004-01-20
•
Expires: 2022-11-27
Abstract
Abstract A diagnostic system and method for a cooling system includes producing a control signal for adjusting a valve position of a regulator valve as a demand for cooling, as well as providing an ambient temperature measurement, coil inlet temperature measurement, and coil exit temperature measurement. The valve position and at least one of the ambient temperature measurement, coil inlet temperature measurement, and coil exit temperature measurement are monitored and compared with at least one predetermined fault value indicative of a fault condition to diagnose the system. An alert module responsive to the diagnostic module issues an alert signal when at least one of the ambient temperature measurement, coil inlet temperature measurement, and coil exit temperature measurement bears a predetermined relationship to the fault value. When monitoring and comparing, an error value percentage indicative of a percentage of sampled error within an accepted offset range for a defined period of time is determined.
Inventors
- 👤 Hung M. Pham
- 👤 Abtar Singh
- 👤 Jean-Luc M. Caillat
- 👤 Mark Bass
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:28
CPC Classifications
F; F25; F25B; F25B49/00; F25B49/02; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/1909; A; A47; A47F; A47F3/00; A47F3/04; F04; F04C; F04C18/00; F04C18/02; F04C18/0207; F04C18/0215; F04C27/00; F04C27/005; F04C28/00; F04C28/02; F04C28/06; F04C28/08; F04C28/18; F04C28/22; F04C28/24; F04C28/26; F04C28/265; F04C28/28; F25B1/00; F25B1/04; F25B41/00; F25B41/20; F25B41/22; F25B49/005; F25B49/022; F25B5/00; F25B5/02; F04C2270/00; F04C2270/01; F04C2270/015; F04C2270/86; F04C23/00; F04C23/008; F25B2400/00; F25B2400/22; F25B2600/00; F25B2600/02; F25B2600/026; F25B2600/0261; F25B2700/00; F25B2700/19; F25B2700/193; F25B2700/1933; F25B2700/21; F25B2700/2106; F25B2700/2117; F25B2700/21174; F25B2700/21175; F25B41/30; F25B41/31; F25B41/34; F25B41/35; Y; Y02; Y02B; Y02B30/00; Y02B30/70
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
157 words
A diagnostic system for a cooling system including a compressor, evaporator and condenser in fluid communication, the diagnostic system comprising: a controller associated with a regulator valve and producing a control signal for adjusting a valve position of said regulator valve as a function of demand for cooling; an ambient temperature sensor associated with the cooling system and operable to provide an ambient temperature measurement to said controller; an evaporator coil inlet temperature sensor associated with the cooling system and operable to provide coil inlet temperature measurement to said controller; an evaporator coil exit temperature sensor associated with the cooling system and operable to provide a coil exit temperature measurement to said controller; a diagnostic module coupled to said controller for monitoring and comparing a valve position and at least one of said ambient temperature measurement, coil inlet temperature measurement and coil exit temperature measurement with at least one predetermined fault value indicative of a fault condition.
Claim 2
Dependent Claim
157 words
A diagnostic system for a cooling system including a compressor, evaporator and condenser in fluid communication, the diagnostic system comprising: a controller associated with a regulator valve and producing a control signal for adjusting a valve position of said regulator valve as a function of demand for cooling; an ambient temperature sensor associated with the cooling system and operable to provide an ambient temperature measurement to said controller; an evaporator coil inlet temperature sensor associated with the cooling system and operable to provide coil inlet temperature measurement to said controller; an evaporator coil exit temperature sensor associated with the cooling system and operable to provide a coil exit temperature measurement to said controller; a diagnostic module coupled to said controller for monitoring and comparing a valve position and at least one of said ambient temperature measurement, coil inlet temperature measurement and coil exit temperature measurement with at least one predetermined fault value indicative of a fault condition.
Claim 3
Dependent Claim
49 words
The diagnostic system of claim 1 , further comprising an alert module responsive to said diagnostic module for issuing an alert signal when said at least one of said ambient temperature measurement, coil inlet temperature measurement and coil exit temperature measurement bears a predetermined relationship to said fault value.
Claim 4
Dependent Claim
23 words
The diagnostic system of claim 1 , wherein said diagnostic module monitors a percentage of sampled error over a defined period of time.
Claim 5
Dependent Claim
17 words
The diagnostic system of claim 3 , wherein said predetermined fault value is an accepted offset range.
Claim 6
Dependent Claim
34 words
The diagnostic system of claim 4 , wherein said diagnostic module determines an error value percentage indicative of said percentage of sampled error within said accepted offset range for said defined period of time.
Claim 7
Dependent Claim
72 words
The diagnostic system of claim 5 , wherein said diagnostic module indicates said electronic stepper regulator valve is stuck open when said error value percentage is approximately zero percent, said valve position of said regulator valve is approximately zero percent for approximately one hundred percent of said defined period of time, said evaporator coil inlet temperature is less than approximately 32° F., and a superheat value is approximately greater than 5° F.
Claim 8
Dependent Claim
35 words
The diagnostic system of claim 6 , wherein said superheat value is a moving average of a difference between said evaporator coil exit temperature and said evaporator coil inlet temperature to approximate said superheat value.
Claim 9
Dependent Claim
71 words
The diagnostic system of claim 5 , wherein said diagnostic module indicates said regulator valve is stuck closed when said error value percentage is approximately zero percent, said valve position of said regulator valve is approximately one hundred percent for approximately one hundred percent of said defined period of time, said evaporator coil inlet temperature is approximately greater than 32° F., and a superheat value is approximately greater than 5° F.
Claim 10
Dependent Claim
35 words
The diagnostic system of claim 8 , wherein said superheat value is a moving average of a difference between said evaporator coil exit temperature and said evaporator coil inlet temperature to approximate said superheat value.
Claim 11
Dependent Claim
104 words
The diagnostic system of claim 5 , wherein said diagnostic system indicates that air flow to the evaporator is blocked or evaporator fans are not operating properly when said valve position of said regulator valve is approximately one hundred percent for approximately one hundred percent of said defined period of time, said error value percentage is approximately zero, a superheat value is approximately less than 5° F., said evaporator coil inlet temperature is approximately less than 25° F., and said evaporator coil exit temperature value is less than said evaporator coil inlet temperature for greater than fifty percent of said defined period of time.
Claim 12
Dependent Claim
35 words
The diagnostic system of claim 10 , wherein said superheat value is a moving average of a difference between said evaporator coil exit temperature and said evaporator coil inlet temperature to approximate said superheat value.
Claim 13
Dependent Claim
51 words
The diagnostic system of claim 1 , wherein said regulator valve is an electronic stepper regulator valve and said control signal for adjusting a valve position of said electronic stepper regulator valve is a variable duty cycle control signal in which said duty cycle is a function of demand for cooling.
Claim 14
Dependent Claim
174 words
The diagnostic system of claim 1 , wherein said diagnostic module monitors and compares at least one of the following conditions: said valve position of said regulator valve; an error value percentage indicative of the percentage of sampled error within an accepted offset range for a defined period of time; a moving average of said valve position for a defined period of time; a steady state loading percentage set equal to said moving average of said valve position for a defined period of time when said error value percentage is less than fifty percent; a discharge cooling fluid temperature; said evaporator coil inlet temperature; said evaporator coil exit temperature; a moving average of a difference between said discharge cooling fluid temperature and said evaporator coil inlet temperature; a moving average of a difference between said evaporator coil exit temperature and said evaporator coil inlet temperature to approximate a superheat value; and a length of time said evaporator coil exit temperature is less than said evaporator coil inlet temperature during a predefined period of time.
Claim 15
Independent Claim
81 words
A method for diagnosing a cooling system, said steps comprising: producing a control signal for adjusting a valve position of a regulator valve as a function of demand for cooling; detecting an ambient temperature measurement, a coil inlet temperature measurement, and a coil exit temperature measurement; and comparing said valve position and at least one of said ambient temperature measurement, coil inlet temperature measurement, and coil exit temperature measurement with at least one predetermined fault value indicative of a fault condition.
Claim 16
Independent Claim
81 words
A method for diagnosing a cooling system, said steps comprising: producing a control signal for adjusting a valve position of a regulator valve as a function of demand for cooling; detecting an ambient temperature measurement, a coil inlet temperature measurement, and a coil exit temperature measurement; and comparing said valve position and at least one of said ambient temperature measurement, coil inlet temperature measurement, and coil exit temperature measurement with at least one predetermined fault value indicative of a fault condition.
Claim 17
Dependent Claim
41 words
The method of claim 14 further comprising the step of issuing an alert signal when said at least one of said ambient temperature measurement, coil inlet temperature measurement, and coil exit temperature measurement bears a predetermined relationship to said fault value.
Claim 18
Dependent Claim
26 words
The method of claim 14 wherein said step of comparing said valve position includes monitoring a percentage of sampled air over a defined period of time.
Claim 19
Dependent Claim
35 words
The method of claim 16 further comprising the step of approximating a superheat value as a moving average of a difference between said evaporator coil exit temperature measurement and said evaporator coil inlet temperature measurement.
Claim 20
Dependent Claim
69 words
The method of claim 17 further comprising the step of indicating said regulator valve is stuck open when said error value percentage is approximately zero percent, said valve position of said regulator valve is approximately zero percent for approximately one hundred percent of said defined period of time, said evaporator coil inlet temperature is less than approximately 32° F., and said superheat value is approximately greater than 5° F.
Claim 21
Dependent Claim
70 words
The method of claim 16 further comprising the step of indicating said regulator valve is stuck open when said error value percentage is approximately zero percent, said valve position of said regulator valve is approximately one hundred percent for approximately one hundred percent of said defined period of time, said evaporator coil inlet temperature is approximately greater than 32° F., and said superheat value is approximately greater than 5° F.
Claim 22
Dependent Claim
103 words
The method of claim 16 further comprising the step of indicating that air flow to the evaporator is blocked or evaporator fans are not operating properly when said valve position of said regulator valve is approximately one hundred percent for approximately one hundred percent of said defined period of time, said error value percentage is approximately zero, said superheat value is approximately less than 5° F., said evaporator coil inlet temperature is approximately less than 25° F., and said evaporator coil exit temperature value is less than said evaporator coil inlet temperature for greater than fifty percent of said defined period of time.
Claim 23
Dependent Claim
28 words
The method of claim 14 wherein said step of adjusting a valve position includes providing a variable duty cycle control signal as a function of demand for cooling.
Claim 24
Dependent Claim
179 words
The method of claim 14 wherein said step of monitoring and comparing a valve position includes monitoring and comparing at least one of the following conditions: said valve position of said regulator valve; an error value percentage indicative of the percentage of sampled error within an accepted offset range for a defined period of time; a moving average of said valve position for a defined period of time; a steady state loading percentage set equal to said moving average of said valve position for a defined period of time when said error value percentage is less than fifty percent; a discharge cooling fluid temperature; said evaporator coil inlet temperature; said evaporator coil exit temperature; a moving average of a difference between said discharge cooling fluid temperature and said evaporator coil inlet temperature; a moving average of a difference between said evaporator coil exit temperature and said evaporator coil inlet temperature to approximate a superheat value; and a length of time said evaporator coil exit temperature is less than said evaporator coil inlet temperature during a predefined period of time.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-01-19 | 2007-07-21 | 2008-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-01-19 | 2011-07-21 | 2012-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-01-19 | 2015-07-21 | 2016-01-20 | $7700.00 | Window Closed / Lapsed |