Roberts Gorden BH15ST BH20ST Furnace User Manual


 
SECTION 3: CLEARANCES TO COMBUSTIBLES
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
Model
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
BH15UT
BH20UT
BH25UT/EF
BH30UT/EF
BH35UT/EF
BH40UT/EF
BH45UT/EF
BH50UT/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
BH15UT
BH20UT
BH25UT/EF
BH30UT/EF
BH35UT/EF
BH40UT/EF
BH45UT/EF
BH50UT/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