Eclipse Combustion RAH Series Manual page 5

NOTE: The blower and the adjoining duct (shown in the darker
shaded areas) are not part of the burner assembly; they
must be purchased and installed separately.
Maximum
Upstream
Temp.
750°F
(400°C)
Min./Max. Velocity: 500 to 6000 fpm
Optimum Velocity:
3.0 Duct Design and Burner Mounting
Duct Design
Support
Air Manifold
Valve Train Support
Gas Piping
Check Valve Piping
Gas Piping Standards
Wiring Standards
Figure 5–Mounting & Duct Lengths
Maximum
Downstream
Temp.
1500°F
(815°C)
2.54 to 30.48 m/s
1000 to 4000 fpm
5.08 to 20.32 m/s
Duct Lengths
Minimum Distance Before Transition
Rectangular Ducts: One Height or Width, Whichever is Greater
Round Ducts: One Diameter
Air Flow
RAH
Burner
See Figure 5 for typical mounting arrangements and duct designs.
The mounting brackets supplied with the burner are capable of supporting the weight
of the burner. Support the blower and air manifold independently of the burner.
The air manifold must be large enough to supply the required combustion air flow with
minimum pressure drop. Do not use more than one 90° bend between the blower and
the burner air inlet.
Support valve trains independently of the burner.
Use flexible nipples to allow for thermal expansion of the burner.
Gas flow through the check valve must be horizontal. See Figure 3.
Gas piping must comply with American National Standard entitled "National Fuel Gas
Code"* (NFPA No. 54 or ANSI Z223.1), or must be acceptable to the authority having
jurisdiction.
Electrical wiring must comply with the National Electric Code*, (NFPA Std. 70 or ANSI-
CI 1981), or must be acceptable to the authority having jurisdiction.
*Available from:
National Fire Protection Association
Batterymarch Park
Quincy, MA 02269
• Provide at least 3" (76 mm) clearance between burner
and top, bottom and sides of the duct.
• Profile plates are not required for good burner opera-
tion, but uniform velocity must be maintained for full
length of burner. If velocity is not uniform, use profile
plates to correct it.
• Center the burner in the duct.
• Allow a minimum of 46" (1168 mm) from burner to
nearest point of possible flame impingement at an
input of 1,000,000 Btu/hr. (962 kW/m).
• Support the blower and motor independently of the
burner.
Maximum
Minimum Distance Before
Possible Flame Impingement = 46"
American National Standard Institute
1430 Broadway
New York, New York 10018
5
7.5°