IP Library › Granted Patent US 4,540,874
Granted Patent Utility
US 4,540,874 · App. 06/570,338

Control system for electric water heater with heat pump external heat source

Inventors: Jacob E. Shaffer, Jr., Joseph F. Picarello
Patented Case View Patent ↗
Granted: Sep 10, 1985 Filed: Jan 13, 1984
Inventors
Jacob E. Shaffer, Jr.
Joseph F. Picarello
Assignee (at issue)
BorgWarner Inc.

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Quick Facts
Patent No.
US 4,540,874
App. No.
06/570,338
Filed
1984-01-13
Granted
1985-09-10
Kind
A