Granted Patent
Utility
US 4,403,572 · App. 06/150,289
Combustion product condensing water heater
Inventors:
Joseph Gerstmann, Andrew D. Vasilakis
Patented Case
View Patent ↗
Granted: Sep 13, 1983
Filed: May 16, 1980
Inventors
Joseph Gerstmann
Andrew D. Vasilakis
Assignee (at issue)
Advanced Mechanical Technology, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.