15619-3
GAS FIRED SEPARATED COMBUSTION AIR HANDLING UNITS
2.4 BLOWER
A. Supply Air: Belt drive motor and blower shall be assembled onto a minimum 14 gauge
galvanized steel platform and must have neoprene vibration isolation devices,
minimum of 1 - 1/8 inches thick.
B. Blower assemblies: Shall be statically and dynamically balanced and designed for
continuous operation at maximum rated fan speed and horsepower.
C. Centrifugal blower housing: Formed and reinforced steel panels to make curved scroll
housing with shaped cutoff.
D. Forward curved blower (fan) wheels: Galvanized or aluminum construction with inlet
flange and shallow blades curved forward in direction of airflow. Mechanically
attached to shaft with set screws.
E. Blower section motor source quality control: Blower performance shall be factory
tested for flow rate, pressure, power, air density, rotation speed and efficiency.
Ratings are to be established in accordance with AMCA 210, "Laboratory Methods
of Testing Fans for Rating".
2.5 MOTORS
A. General: Blower motors greater than .75 horsepower shall be "NEMA Premium"
unless otherwise indicated. Compliance with EPAct minimum energy-efficiency
standards for single speed ODP and TE enclosures is not acceptable. Motors shall be
heavy-duty, permanently lubricated type to match the fan load and furnished at the
specified voltage, phase and enclosure. Drives shall be sized for a minimum of 150%
of driven horsepower and pulleys shall be fully machined cast-type, keyed and fully
secured to the fan wheel and motor shafts. Electric motors of ten horsepower or less
shall be supplied with an adjustable drive pulley.
2.6 UNIT CONTROLS
A. The unit shall be constructed so that it can function as a stand-alone heating system
controlled by factory-supplied controllers, thermostats and sensors or it can be
operated as a heating system controlled by a Building Management System (BMS).
B. Sensors to be provided with the unit include:
1. Heating inlet air sensor
2. 120V/24V smoke detector
2.7 FILTERS
A. Unit shall have 2" thick permanent metal filters located in the outdoor air intake and
shall be accessible from the exterior of the unit.
PART 3 - EXECUTION
3.1 INSTALLATION
A. Install packaged unit in strict accordance with the manufacturer's instructions and
recommendations and as shown on the Drawings.
B. Install wind and seismic restraints according to manufacturer's written instructions
and in accordance with Division 15 Section "Vibration and Seismic Controls for
HVAC Piping and Equipment."
13089K
