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n. Economizer controller shall accept a 2--10Vdc CO
2
sensor input for IAQ/DCV control. In t his mode, dampe rs
shall modulate the outdoor--air damper to provide ventilation based on the sensor input.
o. Compressor lockout sensor shall open at 35_F(2_C) and clo se s at 5 0_F(10_C).
p. Actuator shall be direct coupled to economizer gear. No linkage arms or control rods shall be acceptable.
q. Economizer controller shall provide indica tions when in free cooling mode, in the DCV mode, or the exhaust
fan contact is closed.
2. Two--Position Motorized Damper
a. Damper shall be a Two--Position Motorized Damper. Damper travel shall be from the full closed position to
the field adjustable %--open setpoint.
b. Damper shall include adjustable damper travel from 25% to 100% (full open).
c. Damper shall include single or dual blade, gear driven dampers and act uator motor.
d. Actuator shall be direct coupled to damper gear. No linkage arms or control rods shall be acceptable.
e. Damper will admit up to 100% outdoor air for applicable rooftop units.
f. Damper shall close upon indoor (evaporat or) fan shutoff and/or loss of power.
g. The damper actuator shall plug into the rooftop unit’s wiring harness plug. No hard wiring shall be required.
h. Outside air hood shall include aluminum water entrainment filter
3. Manual damper
a. Manual damper package shall consist of damper, air inlet screen, and rain hood which can be preset to admit
up to 50% outdoor air for year round ventilation.
4. Head Pressure Control Package
a. Controller shall control coil head pressure by condenser--fan speed modulation or condenser--fan cycling and
wind baffles.
b. Shall consist of solid--state control and condenser--coil temperature sensor to maintain condensing temperature
betwee n 90_F(32_C) and 110_ F(43_C) at outdoor ambient temperatures down to --20_F(--29_C).
5. Condenser Coi l Hail Guard Assembly
a. Shall protect against damage from hail.
b. Shall be louvered design.
6. Unit--Mounted, Non--Fused Disconnect Switch:
a. Switch shall be factory--installed, i nternally m ounted.
b. National Electric Code (NEC) and UL approved non--fused switch shall provide unit power shutoff.
c. Shall be accessible from outside the unit
d. Shall provide local shutdown and lockout capability.
7. Convenience Outlet:
a. Powered convenience outlet.
(1.) Outlet shall be powered from main line power to the rooftop unit.
(2.) Outlet shall be powered from line side or load side of disconnect by installing contractor, as required by
code. If outlet is powered from loa d side of disconnect, unit electrical ratings shall be UL certified and
rated for additional outlet amperage.
(3.) Outlet shall be factory--installed and internally mounted with easily accessible 115--v female receptacle.
(4.) Outlet shall include 15 amp GFI receptacles with independent fuse protection.
(5.) Voltage required to operate convenience outlet shall be provided by a factory--installed step--down trans-
former.
(6.) Outlet shall be accessible from outside the unit.
b. Non--Powered convenience outlet.
(1.) Outlet shall be powered from a sepa rate 115--120v power source.
(2.) A transformer shall not be included.
(3.) Outlet shall be factory--installed and internally mounted with easily accessible 115--v female receptacle.
(4.) Outlet shall include 15 amp GFI receptacles.
(5.) Outlet shall be accessible from outside the unit.
8. Thru--t he--Base Connec tors:
a. Kits shall provide connectors to permit electrical connections to be brought to the unit through the unit base-
pan.
b. Minimum of three connection locations per unit.
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