VENT RESTRICTOR
OPENING
Figure 42: Vent restrictor.
The vent restrictor is located on the underside of the firebox top. The unit leaves the factory with the vent
restrictor wide open. The restrictor is built into the appliance for secondary air flow adjustment. Adjustment
enables tuning the airflow for optimum flame appearance and performance for a wide variety of vent
configurations.
Setting:
• Determine the vent height.
• Determine the vent horizontal length.
• From the chart determine the restrictor position.
Refer to the chart in Figure 43 for the correct position of restrictor for the vent configuration of y our
installation. Restrictor positions are based upon lab tests. The ideal position may vary slightly with installation.
Restrictor position is too closed if the flame has the following characteristics:
• Flame is excessively tall and lifting.
• Flame lacks movement.
• Flame soots.
Restrictor position is too open if the flame has the following
characteristics:
• Flame height is low.
• Flame has excessive movement.
To adjust the restrictor:
• Loosen the screw holding the restrictor.
• Move the restrictor to its intended opening.
• Re-tighten the screw.
12'
10'
30'
40'
48'
6'
4'
2'
0'
8'
30'
18"
4'
20'
22'
18'
20'
FULLY OPEN
3" OPEN
2" OPEN
3/4" OPEN LP
10'
0'
1" OPEN NG
6'
8'
10'
12'
14'
16'
18'
20'
Wall and roof
termination restrictor
position
Figure 43: Restrictor position.
28
TC36.CODE_271119-40
100003879
Vent Restrictor Adjustment
