Patent · US Expired

Thermal energy storage to increase furnace efficiency

US4250866A · kind A · utility

20Cited by
9References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 10, 1979
Grant dateFeb 17, 1981
Priority date
Expiry dateSep 10, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/14
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

A forced air furnace includes a conventional fuel fired, primary heat exchanger and a secondary heat exchanger associated with the stack. The secondary exchanger includes a phase change material having a transition temperature within the range of the stack temperature, and which is disposed in heat exchange relation with the flue gases flowing through the stack. The secondary exchanger also includes duct means for conveying the circulated air in heat exchange relation with the phase change material; and the flow path through the secondary exchanger is an alternative path controlled by a damper. When the primary exchanger is turned on, the phase change material in the secondary exchanger is charged from the flue gases of the primary exchanger. When the phase change material is in condition to release stored heat, a temperature responsive control shuts off the primary exchanger and diverts the circulated air through the secondary exchanger.

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