US PATENT SUBCLASS 237 / 54
.~ Upper-room drum

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


237 /   HD   HEATING SYSTEMS

50  DF  AIR {4}
54.~ Upper-room drum

DEFINITION

Classification: 237/54

(under subclass 50) Air heating-systems having a drum in an upper room of the building, through which products of combustion pass.