substitution request - Alliance Construction Solutions

2.03 CENTRIFUGAL FANS:
A. General Description: Belt-driven centrifugal fans consisting of housing, wheel, fan shaft,
bearings, motor and disconnect switch, drive assembly, and support structure.
B. Housings: Fabricated from formed and reinforced galvanized steel panels to form curved
scroll housings with continuously welded or deep-locked seams and access doors or panels to
allow access to internal parts and components.
1. Inlet Cones: Spun metal.
2. Duct Connections: Flanged.
3. Panel Bracing: Steel angle- or channel-iron member supports for mounting and
supporting fan scroll, wheel, motor, and accessories.
C. Fan Wheels: Single-width, single-inlet, welded to cast-iron or cast-steel hub and spun steel
inlet cone, with hub keyed to the shaft.
D. Fan Wheels: Double-width, double-inlet, welded to cast-iron or cast-steel hub and spun steel
inlet cone, with hub keyed to the shaft.
1. Blade Materials: Steel.
2. Blade Type: Backward-curved, flat-plate type.
3. Blade Type: Backward-curved, airfoil type.
4. Blade Type: Forward-curved, airfoil type.
E. Shaft Bearings: Prelubricated and sealed, self-aligning, pillow- block type ball bearings.
F. Accessories: The following accessories are required.
2.04 UTILITY SET FANS:
1. Scroll Bypass Dampers: Aluminum, opposed, airfoil blades with extruded vinyl seals
on blades, low-friction bearings, and positive control linkage for manual or automatic
operation.
2. Scroll Housing Access Doors: Latch-type handles; flush-mounted for uninsulated
housings and raised-mounted for insulated housings.
3. Inlet Vanes: Radial vanes with linkage for manual or automatic operation.
a. Double-Width Fans Inlet Vanes: Connected for single operator.
4. Inlet Screens- Heavy wire mesh screens, mounted inside of shaft bearings.
5. Discharge Dampers: Heavy-gauge steel, opposed blade design, with linkage for
manual or automatic operation.
6. Drain Connections: Threaded, 3/4-inch NPS, capped nipple installed at lowest point
of housing.
7. Shaft Cooler: Metal disc between bearings and fan wheel, designed to dissipate heat
from shaft.
8. Spark-Resistant Construction: AMCA construction option A, B, or C as indicated.
9. Shaft Seals: Air-tight seals installed around shaft on drive side of single-width fans.
10. Special Coatings: Provide protective coatings on fans as indicated.
11. Extended Grease Lines: Extend grease lines from bearings to a convenient, visible
location and terminate with grease fitting.
A. General Description: Belt-driven, centrifugal fans consisting of housing, wheel, fan shaft,
bearings, motor and disconnect switch, drive assembly, and accessories.
Project No.: 10145
550 15 th Street Dual Brand Hotel
03/16/2012
23 3413 - 5 HVAC FANS