The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 25, 1997
Filed:
Sep. 12, 1996
Vijay Bahel, Sidney, OH (US);
Hank Millet, Piqua, OH (US);
Mickey Hickey, Sidney, OH (US);
Hung Pham, Dayton, OH (US);
Gregory P Herroon, Piqua, OH (US);
Gerald L Greschl, Dayton, OH (US);
Copeland Corporation, Sidney, OH (US);
Abstract
Compressor discharge temperature, ambient outdoor air temperature and thermal load are used as control parameters for controlling the expansion valve setting and indoor fan speed. Diagnostics monitor a feedback signal from the fan motor to detect fan over-speed and increased speed due to decreased air flow caused by a dirty indoor air filter. Discharge pressure of the compressor is monitored to detect a blocked outdoor fan. The difference between actual and optimum compressor discharge temperatures and suction pressure of the compressor are monitored to detect a stuck-closed expansion valve or low refrigerant charge. Compressor 'short-cycling' is limited to prevent reduced reliability of the compressor. The difference between compressor discharge temperature and outdoor coil temperature is measured before and after startup to detect compressor failure.