Product data

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respectively (ASTM D2247-92 and ASTM
D870-92). Corrosion durability shall be con-
firmed through testing to be no less than
1000 hours salt spray per ASTM B117-90.
Coil construction shall be aluminum fins
mechanically bonded to copper tubes.
12. Motorized Outdoor Air Damper:
a. Package consisting of dampers, actuator,
and linkages in conjunction with control sys-
tem to provide outdoor air.
b. Dampers shall be an ultra low-leakage type
with blade and edge seals. Dampers shall
exhibit a maximum leakage rate of 4 cfm per
square foot of area at 1 in. wg pressure dif-
ferential when tested in accordance with
AMCA Standard 500.
c. Dampers shall function as intended after
100,000 cycles when tested in accordance
with Section 8, UL standard 555S.
13. Ultra Low Leak Economizer:
Dry bulb, differential dry bulb temperature,
enthalpy, or optional differential enthalpy con-
trolled integrated type consisting of dampers,
actuator, and linkages in conjunction with con-
trol system to provide primary cooling using
outdoor air, enthalpy permitting, supple-
mented with mechanical cooling when
necessary.
a. Economizer shall meet the requirements of
the California Energy commission airside
economizer acceptance test.
b. Dampers shall be an ultra low-leakage type
with blade and edge seals. Dampers shall
exhibit a maximum leakage rate of 4 cfm per
square foot of area at 1 in. wg pressure dif-
ferential when tested in accordance with
AMCA Standard 500.
c. Dampers shall function as intended after
100,000 cycles when tested in accordance
with Section 8, UL standard 555S.
d. Actuator shall have a spring-return feature
which shuts dampers upon a power interrup-
tion or unit shutdown. Actuators are capable
of internal diagnostics.
e. Equipped with a solid-state humidity sensor
that is capable of sensing outdoor-air heat
content (temperature and humidity) and con-
trolling economizer cut-in point at most eco-
nomical level. The user can also configure
dew point limiting.
14. Modulating Power Exhaust with VFD:
Package shall include a double-width, double-
inlet centrifugal belt drive, forward-curved
power exhaust fan with variable frequency drive
control to maintain a field adjustable interior
space pressure set point.
a. Fan bearings shall be of the pillow block type
with an average design life of 200,000
hours.
b. Fans shall be statically and dynamically
balanced.
c. Installation:
1) Site installation shall require supply and
installation of building pressure (BP)
sensing pick-up and tube to connect to
BP transducer in unit.
2) All other wiring and pressure tubing
shall be factory-supplied and factory-
installed.
d. Bypass for the VFD shall be available as a
factory-installed option.
e. A high-static power exhaust option shall be
available.
15. Return Fan/Building Pressure Control:
a. Functions provided shall be:
1) Airflow control for return duct path
(dedicated to overcoming flow losses in
return duct system).
2) Modulate return airflow rate to track
supply fan airflow rate and maintain a
user set delta cfm between the supply
and return airflow.
3) Maintain building pressure by sensing
building pressure and modulating fan
motor speed.
b. Option shall consist of following hardware:
1) Plenum fan assembly, with welded steel
airfoil blade fan.
2) Spring isolation.
3) Belt-drive fan system, fixed pitch for
maximum belt life and reliability.
4) Variable frequency drive (VFD) for
return fan modulation control.
5) Supply air cfm and return air cfm sen-
sors to measure supply and return air-
flow.
6) Exhaust damper with outlet hood.
7) Building pressure transducer.
c. Installation:
1) Site installation shall require supply and
installation of building pressure (BP)
sensing pick-up and tube to connect to
BP transducer in unit.
2) All other wiring and pressure tubing
shall be factory-supplied and factory
installed.
d. A high-static return fan option shall be
available.
16. Extended Lube Lines:
Unit shall be equipped with extended lube lines
to facilitate lubrication of fan bearings from one
side of the unit.