35Heatilator • NDI30, NDI30-SP, NDI35, NDI35-SP, NDI30-SPFK, NDI35-SPFK • 2226-900 Rev. G • 4/11
I. Air Shutter Setting
Air shutter settings should be adjusted by a qualifi ed ser-
vice technician at the time of installation. The air shutter is
set at the factory for minimum vertical vent run. Adjust air
shutter for longer vertical runs. See Figure 12.4.
NOTICE: If sooting occurs, provide more air by opening
the air shutter.
Figure 12.4 Air Shutter
Figure 12.3 Fixed Glass Assembly
H. Fixed Glass Assembly

Removing Fixed Glass Assembly

WARNING! Risk of Asphyxiation! Handle fi xed glass
assembly with care. Inspect the gasket to ensure it is
undamaged and inspect the glass for cracks, chips or
scratches.
•DO NOT strike, slam or scratch glass.
•DO NOToperate fi replace with glass removed, cracked,
broken or scratched.
•Replace as a complete assembly.

Removing Fixed Glass Assembly

•The glass assembly fastens to the fi replace in four
places. Four of the fastening mechanisms are spring-
loaded glass latches. An example of the glass latch
is shown in Figure 12.3.
• To release glass assembly, pull the two bottom
spring-loaded latches forward and allow them to re-
tract away from the glass assembly. Slide the glass
assembly outward and downward until the top latches
disengage.

Replacing Fixed Glass Assembly

•Tilt glass assembly toward fi replace and slide glass
assembly upward to engage top latches. Verify top
latches are fully engaged and then fasten the two
bottom latches.
Air Shutter Settings
NG LP
NDI30 3/8 in. 3/8 in.
NDI35 3/16 in. 1/2 in.