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Heatilator • NNXT33-IFT, NNXT33L-IFT, NNXT36-IFT, NNXT36L-IFT Installation Manual • 2628-980 Rev. C • 8/20
22
H
1
V
1
H
2
H
3
Installed
Horizontally
Installed
Vertically
H
2
Figure 4.14
Two or Three Elbows Installed Horizontally
Top Vent - Horizontal Termination
- (continued)
V
1
Minimum
H
1
+ H
2
Maximum
H
1
+ H
2
+
H
3
Maximum
6 in.
152 mm
6 ft.
1.83 m
-
-
12 in.
305 mm
11 ft.
3.4 m
8 ft.
2.4 m
18 in.
457 mm
17 ft.
5.2 m
14 ft.
4.3 m
24 in.
610 mm
17 ft.
5.2 m
14 ft.
4.3 m
V
1
+ H
1
+ H
2
= 50 ft. (15.24 m) Maximum
V
1
+ H
1
+ H
2
+ H
3
= 47 ft. (14.33 m) Maximum