Robertshaw Controls Company

Ronald E Holkeboer

Anthony C Cairo

Frederick T Bauer

Gary E Tyler

An electrical primary control system for furnaces and method of making the same, the system comprising burner control means, an isolated low voltage control circuit and means for interfacing between the isolated low voltage control circuit and the burner control means; the interfacing means including a pair of resilient, magnetic reeds disposed within a hermetically sealed envelope, and a pair of electrically insulated independently wound coils having a differential in ampere turns and encompassing the envelope, the magnetic flux generated by such coils being additive whereby energization of both of the coils is required to close the contacts but energization of one of the coils is sufficient to maintain the contacts closed, at least one of the coils having a resistance wire of predetermined calibrated resistance electrically connected in parallel circuit therewith.

Primary control system for furnaces and method of making the same

A solid state stack switch control system for furnaces and the like including burner control means, means including solid state means effective to control said burner control means in response to thermally actuated, magnetically operated heat detection means, line voltage safety switch means, and means for interfacing between an isolated low voltage control circuit and said burner control means.

Growing community of inventors

Holland, MI, United States of America

Ronald E Holkeboer