United States Stove Company 6300C - Manual (Page 11)

USSC 11
Installation
PRIMARY FURNACE
SECONDARY (ADD-ON) FURNACE
When installed as a seondary furnace, a Duct Damper must be installed between the air discharge of the 6300 furnace
and the primary (Gas, Electric, etc.). This duct damper prevents the air from the primary furnace from back flowing to the
secondary furnace. Damper must be a mechanical (spring return) style with a simple closure switch to determine if the
damper is opened or closed. The damper will connect to the multi-fuel furnace’s printed circuit board (PCB). See wiring
diagram in this manual.