OUTSIDE COMBUSTION AIR PRECAUTIONS & RECOMMENDATIONS
NOTE: The use of outside air for combustion is optional unless required by building codes. It is only necessary to supply outside combustion air to one side of the fireplace. Use the model AK4 combustion air kit.
FIGURE 23
INSULATION RING
INSERT SHORTEST SIDE
OF THE TUBE THROUGH
THE FIREPLACE OUTER
WRAP TO PROPERLY
SEAL AGAINST FIREBOX
WALL AND GASKET.
SECURING OUTSIDE AIR STARTING COLLAR TO FIREPLACE
LONGER LENGTH OF THE TUBE
TO OUTSIDE.
STEP 1: SECURE OUTSIDE AIR STARTING
COLLAR TO LEFT SIDE OF FIREPLACE WITH
FOUR SHEET METAL SCREWS PROVIDED.
NOTE: THE STARTING COLLAR EXTENDS
THROUGH THE OUTER FIREPLACE JACKET
AND WILL SEAL AGAINST THE FIREBOX
WALL WHEN SECURED AS INDICATED.
SECOND FLOOR
FIRESTOP SPACER
TERMINATION CAP
DUCT EXTENDED
TO MISS JOIST
STEP 2: SECURE OUTSIDE DUCT TO STARTING COLLAR WITH DUCT CLAMP OR SCREWS.
FIREPLACE OUTER WRAP
AK4 COMBUSTION
AIR KIT (SHORTEST
TOWARD FIREBOX)
AK4 MOUNTING PLATE
FIREBOX INSULATION SEAL
FIRESTOP SPACER
TO OUTSIDE WALL 
INSTALLATION ABOVE BASEMENT
OR CRAWL SPACE
CAUTION: DO NOT TAKE
COMBUSTION AIR FROM
ATTIC SPACE OR GARAGE.
INLET GRILLE
8' MAX. IN SOFFIT (OVERHANG)
CONCRETE SLAB INSTALLATION (OPTIONAL OUTSIDE AIR RUNS)
21
53D9028. Rev 1 03/03