Excess air control
US4703747A · kind A · utility
38Cited by
4References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 17, 1986 |
| Grant date | Nov 3, 1987 |
| Priority date | — |
| Expiry date | Sep 17, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23N2233/10
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Method and apparatus for maintaining excess air control in a gas furnace. A pressure switch is placed across a heat exchanger to indicate when, while accelerating the inducer motor speed during purging operation, the pressure drop reaches a predetermined level. When that occurs, the motor speed is sensed and recorded. When the furnace is subsequently fired, the desired inducer motor speed is obtained by modifying the recorded motor speed on a correction factor derived from empirical data obtained from a gas furnace operating under selective variable conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.