Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4267884 | Heat recovery device for use in return air duct of forced air furnace for recovering heat from the flue of such furnace | — | 1981-05-19 |
| 4232654 | Heat recovery device for use in return air duct of forced air furnace for recovering heat from the flue of such furnace | — | 1980-11-11 |