High efficiency modulating gas furnace
US10648664B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 2017 |
| Grant date | May 12, 2020 |
| Priority date | — |
| Expiry date | Mar 25, 2038 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24H15/414
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A high-efficiency modulating gas furnace (herein ‘gas furnace’) includes a furnace controller. The gas furnace further includes a gas valve and at least one pressure switch that is coupled to the furnace controller. The electrical contacts of the at least one pressure switch are removed from a series electrical circuit with the gas valve such that the gas furnace operates without de-energizing the gas valve as soon as the electrical contacts of the at least one pressure switch are opened. Further, the furnace controller operates the induced draft blower at or close to a lowest RPM at which the electrical contacts of the at least one pressure switch can be kept closed, which is between a make point RPM at which the electrical contacts of the at least one pressure switch close and a break point RPM at which the electrical contacts of the at least one pressure switch open.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.