Roberts Gorden Vacuum Assisted Linear - Manual (Page 15)

SECTION 3: C LEARANCES TO C OMBUSTIBLES
9 of 75
NOTE: 1. All dimensions are from the surfaces of all tubes, couplings, tees, elbows and crosses.
2. Clearances B, C and D can be reduced by 50% after 7500 mm of tubing downstream
from the burner.
3. All measurements are in millimeters.
4. Add 60 mm clearance to uncovered U-tube.
FIGURE 15: U-TUBE, OPPOSITE 45° TILT
Mo
de
l
BH15UT BH20UT BH25UT/EF BH30UT/EF BH35UT/EF BH40UT/EF BH45UT/EF BH50UT/EF
A 200 200 200 250 250 275 300 300
B 1370 1530 1530 1630 1780 1830 1880 1930
C 1500 1650 1650 1860 1960 2040 2110 2160
D 560 560 560 560 560 560 560 560
A
C
D B
FIGURE 16: U-TUBE, PROTECTIVE GRILLE
Model BH
1
5
U
T
BH
2
0
U
T
BH
2
5
U
T
/EF
BH
3
0
U
T
/EF
BH
3
5
U
T
/EF
BH
4
0
U
T
/EF
BH
4
5
U
T
/EF
BH
5
0
U
T
/EF
A 150 150 150 150 150 150 200 200
B 890 970 970 1020 1170 1220 1270 1380
C 1580 1730 1730 1910 1980 2050 2110 2210
D 760 940 940 1000 1090 1150 1200 1300
A
C
D B
FIGURE 17: U-TUBE, VENTING
Model BH
1
5
U
T
BH
2
0
U
T
BH
2
5
U
T
/EF
BH
3
0
U
T
/EF
BH
3
5
U
T
/EF
BH
4
0
U
T
/EF
BH
4
5
U
T
/EF
BH
5
0
U
T
/EF
E 1000 1000 1000 1000 1000 1000 1000 1000
F 500 500 500 500 500 500 500 500
Radiant tubes Fan
Unvented
Vented
E
F