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3. Shall consist of factory--installed, low velocity, throw--away 2--in. thick fiberglass filters.
4. Filters shall be standard, commercially available sizes.
5. Only one size filter per unit is allowed.
23 81 19.13.M. Evaporator Fan and Motor
1. Evaporator fan motor:
a. Shall have permanently lubricated bearings.
b. Shall have inherent automatic--reset thermal overload protection or circuit breaker.
c. Shall have a maximum continuous bhp rating for continuous duty operation; no safety factors above that rating
shall be required.
2.ElectricDrive(DirectDrive)X13–5Speed/TorqueEvaporatorFan:
a. Multi speed motor with easy quick adjustment settings.
b. Blower fa n shall be double--inlet type with forward--curve d blades.
c. Shall be constructed from steel with a corrosion resistant finish and dynamically balanced.
d. Standard on all 04--06 models with 208/230/1/60 operation
e. Standard on all 04--06 3--phase models, with optional belt drive.
3. Belt--driven E vaporator Fan:
a. Belt drive shall include an adjustable --pitch motor pulley.
b. Shall use sealed, permanently lubricated ball--bearing type.
c. Blower fan shall be double--i nlet type with forward--c urved blades.
d. Shall be constructed from steel with a corrosion resistant finish and dynamically balanced.
e. Standard on all 07 size models. Optional on all 04--06 3--phase models.
23 81 19.13.N. Condenser Fans and Motors
1. Condenser fa n motors:
a. Shall be a totally enclosed motor.
b. Shall use permanently lubricated bearings.
c. Shall have inherent thermal overload protection with an automatic reset feature.
d.Shalluseashaft--downdesignon04to09models.
2. Condenser Fans:
a. Shall be a direct--driven propeller type fan.
b. Shall have alumi num blades riveted to corrosion--resista nt steel spiders and shall be dynamically balanced.
23 81 19.13.O. Special Features, Options and Accessories
1. Integrated Economizers:
a. Integrated, gear--driven parallel modulating blade design type capable of simultaneous economizer and com-
pressor operation.
b. Independent modules for vertical or horizontal return configurations shall be available. Vertical return modules
shall be available as a factory installed option.
c. Damper blades shall be galvanized steel with composite gears. Plastic or composite blades on intake or return
shall not be acceptable.
d. Shall include al l hardware and controls to provide free cooling with outdoor air when temperature and/or hu-
midity are below setpoints.
e. Shall be equipped with gear driven dampers for both the outdoor ventilation air and the return air for positive
air stream control.
f. Shall be equipped with low--leakage dampers, not to exceed 2% leakage at 1 in. wg pressure differential.
g. Shall be capable of introducing up to 100% outdoor air.
h. Shall be equipped with a ba rometric relief damper capable of re lieving up to 100% return air.
i. Shall be designed to close damper(s) during loss-- of --power situations with spring return built into motor.
j. Dry bulb outdoor--air temperature sensor shall be provided as standard. Outdoor air sensor setpoint shall be
adjustable and shall range from 40 to 100_F/4to38_C. Additional sensor options shall be available as ac-
cessories.
k. The economizer controller shall also provide control of an accessory power exhaust unit function. Factory set
at 100%, with a range of 0% to 100%.
l. The economizer shall maintain minimum airflow into the building during occupied period and provide design
ventilation rate for full occupancy. A remote potentiometer may be used to override the damper setpoint.
m. Dampers shall be completely closed when the unit is in the unoccupied mode.
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