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Heatilator • NNXT33-IFT, NNXT33L-IFT, NNXT36-IFT, NNXT36L-IFT Installation Manual • 2628-980 Rev. C • 8/20
24
Lift top refractory
and hold in place
Pull side refractory
forward & out
Figure 4.18 Remove Side Refractory
• Remove the side refractory:
- Gently raise the front of the top refractory.
- Lift the side piece up slightly and then out.
• Remove top refractory:
- Lower towards side removed in previous step.
- Gently twist out.
Lower & twist; pull out
Figure 4.19 Remove Top Refractory
• Remove two screws from firebox top.
• Using these screws and the same holes, install the top
vent flue baffle.
- The flue baffle will be turned to install below the level
of the firebox top for 12-30 ft. vertical runs of vent.
See Figure
4.20
.
- The flue baffle will be turned to install inside the flue
for vertical vent runs of 31-60 ft. See Figure 4.21.
Figure 4.20 12-30 Foot Vertical Run
Figure 4.21 31-60 Foot Vertical Run
Place flue baffle,
reinsert screws
Place flue baffle,
reinsert screws
• Reinstall Refractory:
- Replace top refractory.
- Lift top refractory and slide side refractory back into
position.
- Replace bottom retainer.