SECTION 3: C
RITICAL
C
ONSIDERATIONS
7 of 91
NOTE:
1. All dimensions are from the s
u
rfaces of all t
u
bes, co
u
plings and elbo
w
s.
2. Clearances B, C and D can be red
u
ced by 50% after 25' (7.5 m) of t
u
bing do
w
nstream from
w
here the b
u
rner and b
u
rner t
u
be connect.
FIGURE 7: U-TUBE, STANDARD REFLECTOR
(inches)
(centimeters)
Model
A
B
C
D
A
B
C
D
CTHN-40
- UNAPPROVED -
- UNAPPROVED -
CTHN-60
5
27
56
19
13
69
142
48
CTHN-80
5
30
61
20
13
76
155
51
CTHN-100
5
32
63
20
13
81
160
51
CTHN-125
5
35
66
20
13
89
168
51
CTHN-150
5
39
73
21
13
99
185
53
CTHN-175
8
44
75
26
20
112
191
66
CTHN-200
8
47
76
30
20
119
193
76
FIGURE 8: U-TUBE, 45
°
(inches)
(centimeters)
Model
A
B
C
D
A
B
C
D
CTHN-40
- UNAPPROVED -
- UNAPPROVED -
CTHN-60
8
4
47
40
20
10
119
102
CTHN-80
8
4
54
46
20
10
137
117
CTHN-100
8
4
57
48
20
10
145
122
CTHN-125
8
4
63
53
20
10
160
135
CTHN-150
8
4
66
56
20
10
168
142
CTHN-175
8
4
69
59
20
10
175
150
CTHN-200
8
4
73
63
20
10
185
160
B
C
D
A
FIGURE 9: U-TUBE, OPPOSITE 45
°
REFLECTOR
(inches)
(centimeters)
Model
A
B
C
D
A
B
C
D
CTHN-40
- UNAPPROVED -
- UNAPPROVED -
CTHN-60
8
45
45
10
20
114
114
25
CTHN-80
9
55
54
10
23
140
137
25
CTHN-100
10
56
57
10
25
142
145
25
CTHN-125
10
58
63
10
25
147
160
25
CTHN-150
10
61
66
20
25
155
168
51
CTHN-175
10
68
69
20
25
173
175
51
CTHN-200
10
71
73
20
25
180
185
51
A
C
D
B
