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t. Actuator shall be direct coupled to economizer gear. No linkage arms or c ontrol rods shall be acceptable.
u. Economizer controll er shall provide indications when in free cool ing mode, in the DCV mode, or the ex-
haust fan contact is closed.
4. Integrated EconoMi$er2, and EconoMi$er X Ultra Low Leak rate models.(Fact ory installed on 3 phase model s
only. Field installed on all 3 and 1 phase models)
a. Integrated, gear driven opposing modulating blade design type capable of simultaneous e conomiz er and
compressor opera tion.
b. Independent modules for vertical or horizontal re turn configura tion shall be avai lable . Vertical return mod-
ules shall be available as a fact ory installed option.
c. Damper blades shall be galvanized steel with composite gears. Plastic or composite blades on intake or re-
turn shall not be acceptable.
d. Shall include all hardware and cont rols to provide free cooling with outdoor air whe n tempe rature and/or
humidity are below setpoints.
e. Shall be equipped with gear driven dampers for both the outdoor ventilation a ir and the return air for posi-
tive air stream control
f. Ultra Low Leak design meets California Title 24 section 140.4 and ASHRAE90.1 requirements for 4 cfm
per sq.ft. on the outside air da mpers and 10 cfm per sq. ft. on the return dampers.
g. Economizer controll er on EconoMi$er X m odels shall be the Honeywell W7220 that provides:
(1.) 2 --line L CD interfac e screen for setup, configuration and troubleshooting
(2.) On--boa rd Fault Dete ction and Diagnostics (FDD) that senses and alerts when the economiz er is not
operating properly, per California Title 24.
(3.) Sensor failure loss of communication identification
(4.) Automatic sensor detection
(5.) Capabilities for use with multiple --speed indoor fan systems
(6.) Utilize digital sensors: Dry bulb and Enthalpy
h. Economizer controll er on EconoMi$er 2 models with RTU Open models shall be a 4--20mA design con-
trolled directly by the RTU Open controller. RTU Open meets California Title 24 Fault Detection & Diag-
nostic (FDD) requirements.
i. Shall be capable of i ntroducing up to 100% outdoor air.
j. Shall be equipped with a barometric relief damper capable of reli eving up to 100% return air and contain
seals that meet ASHRAE 90.1 requirements.
k. Shall be designed to close damper(s) during loss--of--power situations with spring return built into motor.
l. Dry bulb outdoor air te mperat ure sensor shall be provided as standard. Enthalpy sensor is a lso available on
fact ory install ed only. Outdoor air sensor set point shall be adjustable and shall range from 40 to 100° F/4
to 38° C. Additional sensor options shall be available as accessories.
m. 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%.
n. The economizer shall maintain mi nimum airflow into the building during occupi ed period and provide
design ventilation rate for full occupancy.
o. Dampers shall be complete ly closed when the unit is i n the unoccupied mode.
p. Economizer controller shall accept a 2--10 Vdc CO
2
sensor input for IAQ/DCV control. In this mode,
dampers shall modulate the outdoor air damper to provide ventilation based on the sensor input.
q. Compressor lockout temperature on W7220 is adjustable from --45° Fto80° F, set at a factory default of
32° F. Others shall open at 35°F(2°C) and closes at 50°F(10°C).
r. Actuator shall be direct coupled to economizer gear. No linkage arms or control rods shall be acceptable.
s. Economizer controller shall provide indications when in free cooling mode, in the DCV mode, or the ex-
haust fan contact is closed.
5. Two--Position Damper (Factory installed on 3 Phase Models Only. Field installed on all 3 and 1 Phase Models)
a. Damper shall be a Two--Position Damper. Damper travel shall be from the full closed position to the field
adjustable %--open setpoint.
b. Damper shall include adjustable da mper travel from 25% to 100% (full open).
c. Damper shall include single or dual blade, gear driven dampers and actua tor motor.
d. Actuator shall be direct coupled to damper gear. No linkage arms or control rods shall be acceptable.
e. Damper will a dmit up t o 100% outdoor air for applicable rooftop units.
f. Damper shall close upon indoor (evaporator) fan shutoff a nd/or loss of power.
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