#ABY R.2 October 2020
Hussong Mfg. Co., Inc. • Kozy Heat Fireplaces
INSTALLATION PLANNING
19
3.10.1 Combustion Air Intake - Air Trap
•
An optional air trap can be used in venting configurations 1
through 3 in Figure 3.7 below.
•
An air trap is REQUIRED on venting configuration 4 when the
combustion air intake is above the air intake collar on the
fireplace.
3.10.2 Combustion Air Duct Installation
IMPORTANT: Maximum air duct vent pipe length is 25’ (7.6m).
1. Connect a 4” (102mm) galvanized or heavier pipe to the air
intake collar, and run to the nearest outside wall. Secure with
screws. See venting configurations
below.
2. Aluminum flex duct pipe is approved for outside combustion air,
and may also be used. Do not crush or tear aluminum flex duct
pipe. Do not use plastic pipe.
3. Use 4” flexible duct pipe for vent runs under 10’ (3m). For vent
runs longer than 10’ (3m), use 5” aluminum flex duct pipe. Place
the 4” to 5” adapter as close to the fireplace as possible.
4. If ducting beside the chimney chase, terminate intake air at least
3’ (914mm) below the termination level of chimney. The air pipe
may also be ducted below floor level of the fireplace, providing it
is ducted to the outside.
5. Mount a standard metal vent cover designed for a 4” (102mm)
pipe on outside exterior wall, with the louvers pointing
downward. Use a 5” metal vent cover if you increased the air duct
vent size in Step 4.
Figure 3.10, Combustion Air Duct Venting Configurations
8”
12”
Hearth extension
Metal sealing strip centered under
fireplace and hearth extension for
the full width of the fireplace
Termination
above air
intake collar
Air trap
VENTING CONFIGURATIONS
1
2
3
4
Nominal 2“ x 4” framing used
