Data processing: measuring – calibrating – or testing – Measurement system – Performance or efficiency evaluation
Reexamination Certificate
2001-08-24
2003-12-02
Hoff, Marc S. (Department: 2857)
Data processing: measuring, calibrating, or testing
Measurement system
Performance or efficiency evaluation
C702S183000, C062S125000
Reexamination Certificate
active
06658373
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to heating/ventilation/air conditioning/refrigeration (HVACR) systems and, more specifically, to detecting faults in a system utilizing a vapor compression cycle under actual operating conditions and providing diagnostics for fixing the detected faults.
BACKGROUND OF THE INVENTION
Air conditioners, refrigerators and heat pumps are all classified as HVACR systems. The most common technology used in all these systems is the vapor compression cycle (often referred to as the refrigeration cycle), which consists of four major components (compressor, expansion device, evaporator, and condenser) connected together via a conduit (preferably copper tubing) to form a closed loop system. The term refrigeration cycle used in this document refers to the vapor compression used in all HVACR systems, not just refrigeration applications.
Light commercial buildings (e.g. strip malls) typically have numerous refrigeration systems located on their rooftops. Since servicing refrigeration systems requires highly skilled technician to maintain their operation, and there are few tools available to quantify performance and provide feedback, many of refrigeration cycles are poorly maintained. Two common degradation problems found in such commercial systems are fouling of the evaporator and/or condenser by dirt and dust, and improper refrigerant charge.
In general, maintenance, diagnosis and repair of refrigeration systems are manual operations. The quality of the service depends almost exclusively upon the skill, motivation and experience of a technician trained in HVACR. Under the best circumstances, such service is time-consuming and hit-or-miss opportunities to repair the under-performing refrigeration system. Accordingly, sometimes professional refrigeration technicians are only called upon after a major failure of the refrigeration system occurs, and not to perform routine maintenance on such systems.
Attempts to automate the diagnostic process of HVACR systems have been made. However, because of the complexity of the HVACR equipment, high equipment cost, or the inability of the refrigeration technician to comprehend and/or properly handle the equipment, such diagnostic systems have not gained wide use.
SUMMARY OF THE INVENTION
The present invention includes an apparatus and a method for fault detection and diagnostics of a refrigeration, air conditioning or heat pump system operating under field conditions. It does so by measuring, for each vapor compression cycle, at least five—and up to nine—system parameters and calculating system performance variables based on the previously measured parameters. Once the performance variables of the system are determined, the present invention provides fault detection to assist a service technician in locating specific problems. It also provides verification of the effectiveness of any procedures performed by the service technician, which ultimately will lead to a prompt repair and may increase the efficiency of the refrigeration cycle.
The present invention is intended to be used with any manufacturer's HVACR equipment, is relatively inexpensive to implement in hardware, and provides both highly accurate fault detection and dependable diagnostic solutions which does not depend on the skill or abilities of a particular service technician.
REFERENCES:
patent: 4325223 (1982-04-01), Cantley
patent: 4381549 (1983-04-01), Stamp, Jr. et al.
patent: 4510576 (1985-04-01), MacArthur et al.
patent: 4755957 (1988-07-01), White et al.
patent: 4798055 (1989-01-01), Murray et al.
patent: 4928278 (1990-05-01), Otsuji et al.
patent: 4967567 (1990-11-01), Proctor et al.
patent: 5003256 (1991-03-01), Merrill
patent: 5010743 (1991-04-01), Hale
patent: 5115643 (1992-05-01), Hayata et al.
patent: 5209076 (1993-05-01), Kauffman et al.
patent: 5231598 (1993-07-01), Vlahos
patent: 5239865 (1993-08-01), Salzer et al.
patent: 5595507 (1997-01-01), Braun et al.
patent: 5596507 (1997-01-01), Jones et al.
patent: 5623834 (1997-04-01), Bahel et al.
patent: 5666815 (1997-09-01), Aloise
patent: 5760478 (1998-06-01), Bozso et al.
patent: 5934088 (1999-08-01), Takeda
patent: 5991890 (1999-11-01), Brown et al.
patent: 6128910 (2000-10-01), Faircloth
patent: 6223544 (2001-05-01), Seem
patent: 6272868 (2001-08-01), Grabon et al.
patent: 6324854 (2001-12-01), Jayanth
patent: 6360551 (2002-03-01), Renders
Douglas Jonathan D.
Rossi Dale
Rossi Todd M.
Stockman Timothy P.
Barbee Manuel L.
Field Diagnostic Services, Inc.
Garzia Mark A.
Hoff Marc S.
Mark A. Garzia, P.C.
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