21
DX3
Series
Optional Elbow or U-Bend Accessory Configuration
A 90 degree elbow or 180 degree U-bend accessory fitting may be installed in the radiant tube heating
system. Refer to Chart 3.3 on page 22 for minimum distance requirements from the burner control box.
When installing an Elbow or U-Bend Accessory Fitting:
• The top clearance of an uncovered (no reflector) elbow or U-bend accessory fitting to
combustibles is 18 in.
• If operating the heater unvented, separate the intake air to the heater from its exhaust products a
minimum of 4 ft., further separation may be necessary. Combustion air may also be supplied.
• A maximum of two 90° elbows or one 180° U-bend can be installed on a heater.
• Remove one 36 in. section of baffle.
Refer to baffle assembly section on page 26.
3
Slip-fit the radiant tube sections together until tightly connected (install the swaged end of each tube
towards exhaust end).
NOTE:
If it is difficult to mate the tubes, they may be installed incorrectly.
4
Center tube clamps over the seam where two radiant tube sections connect. If necessary, rotate tube
clamps so they will not interfere with the reflector end caps during expansion and contraction of
the heater.
5
Tighten tube clamp bolts to secure. When proper compression is obtained (40-60 ft-lbs. torque) the
tube seam will create a visible mark on the tube clamp.
NOTE:
Excessive torque may damage the
tube clamp.
6
Determine the location of the burner control box and note the placement of the mounting chains.
Figure 3.10
•
Tube Connections
Tubes fit snuggly together and the
tube clamp is centered over the seam.
Tubes are not fit snuggly
together and the tube clamp is
not centered over the seam.
The tube clamp is tight when the
torque is achieved (normally
when seam becomes visible).
Correct Tube Connection
Incorrect Tube Connection
90 Degree Elbow Bend
180 Degree
U-Bend
(P/N: TF1B)
(P/N: E6)
3.0
Installation
•
Optional Elbow or U-Bend Accessory Configuration
Figure 3.11
•
Optional Tube Connections
