Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4498220 | Method for pre-expanding heat exchanger tube | Donald S. Fiegen | 1985-02-12 |
| 4359086 | Heat exchange surface with porous coating and subsurface cavities | Duane F. Sanborn, John L. M. Holman | 1982-11-16 |
| 4232533 | Multi-stage economizer | James T. Lundblad | 1980-11-11 |
| 4223537 | Air cooled centrifugal water chiller with refrigerant storage means | Duane F. Sanborn | 1980-09-23 |
| 4220011 | Air cooled centrifugal refrigeration system with water heat recovery | Mark O. Bergman, John W. Leary, Duane F. Sanborn | 1980-09-02 |