Patent · US Expired

Apparatus and method for furnace combustion control

US5666889A · kind A · utility

19Cited by
2References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 27, 1995
Grant dateSep 16, 1997
Priority date
Expiry dateMar 27, 2015

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF23N2237/10
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

Furnace combustion in a multi-stage or variable input furnace is controlled by operating the furnace in a high fire mode at furnace start-up until the temperature of the products of combustion, or a temperature corresponding to the products of combustion, equals or exceeds a selected temperature. A temperature sensor, preferably a thermostat, is located downstream of the furnace zone of combustion (e.g., in a flue collector box at an outlet from the heat exchanger). The thermostat provides an indication of the products of combustion temperature and has a set point corresponding to the selected temperature. When the products of combustion temperature is less than the selected temperature, the thermostat contacts remain closed. The furnace is operated in the high fire mode while the thermostat contacts remain closed in response to a demand for heating, irrespective of whether the demand is for first stage or second stage heating. When the selected temperature is reached, the thermostat contacts open, thereby allowing the furnace to be operated in either the high fire or in a low fire mode, depending on the level of demand for heating, as indicated by an external room thermostat. By o…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.