Roberts Gorden NDUSTRIA NHE Series Installation, Operation & Service Manual page 11

NOTE: 1. All dimensions are from the surfaces of all tubes, couplings and elbows.
2. Clearances B, C and D can be reduced by 50% after 25' (7.5 m) of tubing downstream
from where the burner and burner tube connect.
FIGURE 9: 2-FOOT DECO GRILLE AND PROTECTIVE GRILLE
A
C
B
D
FIGURE 10: LOWER CLEARANCE SHIELD*
A
B
D
C
*When installed in the first 10' (3 m).
FIGURE 11: VENTING
A
E
Unvented
Radiant Tubes
Vented
Model
NHE-40
NHE-60
NHE-80
NHE-100
NHE-125
NHE-150
NHE-175
Model
NHE-40
NHE-60
NHE-80
NHE-100
NHE-125
NHE-150
NHE-175
Model
NHE-40
Vent NHE-60
Pipes
NHE-80
NHE-100
NHE-125
F
NHE-150
NHE-175
(inches)
A B C
6 27 53
6 35 63
6 38 66
6 40 71
6 46 77
6 50 80
8 52 82
(inches)
A B C
6 34 27
6 39 33
6 40 38
6 50 44
6 54 48
6 55 50
- UNAPPROVED -
(inches)
A E F
14 18 18
14 18 18
20 24 18
20 24 18
20 24 18
20 30 18
20 30 18
SECTION 3: C
LEARANCES TO
(centimeters)
D A B
27 16 69
35 16 89
38 16 97
40 16 102
46 16 117
50 16 127
52 21 133
(centimeters)
D A B
34 16 87
39 16 100
40 16 102
50 16 127
54 16 138
55 16 140
- UNAPPROVED -
(centimeters)
A E
36 46
36 46
51 61
51 61
51 61
51 77
51 77
C
OMBUSTIBLES
C D
135 69
161 89
168 97
181 102
196 117
204 127
209 133
C D
69 87
84 100
97 102
112 127
122 138
127 140
F
46
46
46
46
46
46
46
7