Outdoor Air - Lennox Energence LCH Manual

O PT IO N S / A C C ES S ORIES
ECONOMIZER (continued)
Global Control
• The unit controller communicates with a DDC system
with one global sensor (enthalpy or sensible)
• Determines whether outside air is suitable for free
cooling on all units connected to the control system
• Sensor must be field provided
Factory or Field Installed
Single Enthalpy Temperature Control (Not for Title 24)
• Outdoor air enthalpy sensor enables Economizer if the
outdoor enthalpy is less than the setpoint of the control
Differential Enthalpy Control (Not for Title 24)
• Order two Single Enthalpy Controls
• One is field installed in the return air section
• One is installed in the outdoor air section
• Allows the economizer control to select between
outdoor air or return air, whichever has lower enthalpy
Field Installed
Outdoor Air CFM Control
• Maintains constant outdoor air volume levels on the
supply air fan and varying unit airflows
• Velocity sensor located in the rooftop unit outdoor air
section, the Prodigy 2.0 unit controller changes the
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economizer position to help minimize the effect of
supply fan speed changes on outdoor air volume levels
• Setpoint for outdoor air volume is established by field
testing
NOTE - Not available with Demand Control Ventilation
(CO2 Sensor) or Building Pressure Control.
Building Pressure Control
• Maintains constant building pressure level
• Includes a static pressure transducer and outdoor static
pressure assembly
• Using differential pressure information between the
outdoor air and the building air, the Prodigy
controller changes the economizer position to help
maintain a constant building pressure
NOTE - Not available with Demand Control Ventilation
(CO2 Sensor) or Outdoor Air CFM Control.
EXHAUST
Factory or Field Installed
Power Exhaust Fan
• Installs internal to unit for downflow applications only
with economizer option
• Provides exhaust air pressure relief
• Interlocked to run when supply air blower is operating,
• Fan runs when outdoor air dampers are 50% open
(adjustable)
• Motor is overload protected
• Fan is 508 mm diameter
• Five blades
• One 0.25 kW motor
NOTE - Requires Economizer and Downflow Barometric
Field Installed
Horizontal Low Profile Barometric Relief Dampers
• For use when unit is configured for horizontal
applications requiring an economizer
• Allows relief of excess air
• Aluminum blade dampers prevent blow back and
outdoor air infiltration during off cycle
• Field installed in return air duct
• Bird screen and hood furnished
NOTE - Requires Horizontal Discharge Kit

OUTDOOR AIR

Factory or Field Installed
Outdoor Air Damper
• Downflow or Horizontal
• Linked mechanical dampers
• 0 to 25% (fixed) outdoor air adjustable
• Installs in unit
2.0 unit
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• Includes outdoor air hood
• Automatic model features fully modulating spring return
damper motor with plug-in connection
• Manual model features parallel blade, gear-driven
dampers with adjustable fixed position
Energence
Relief Dampers
Packaged Electric / Electric 26 to 44 kW 50 Hz / Page 9
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