Manual

FlexStat 12 Operation Guide, Rev. R
NOTE: Not all applications have a modulating
economizer option. Withoutamodulating
economizerselected,DCVwillnotappear
inanymenus,but the (Advanced) CO
2
Sensor menu will remain and the CO
2
ppm
readings will still show on the display.
NOTE: An alarm is generated when the CO
2
level is
too high for too long. See Alarms on page 23.
NOTE: The various Outside Air (OA) % seings
available are the percentage that the OA
damperisopen and not the percentage
of OA ow. These seings should be
measured and set accordingly.
NOTE: SeetheDCVsectionintherelevant
SequenceofOperationoftheFlexStat
ApplicationGuideformoreinformation
aboutthemodesandoptionsdescribedin
generaltermshere.
ThethreetypesofDCVcongurationsavailable
are:
• BASICDCV—Provides simple DCV, modulat-
ing the outside air damper in direct response to
the current CO
2
level with respect to its setpoint.
Basic DCV is much more energy ecient than no
DCV at all, while maintaining adequate IAQ (In-
door Air Quality). It is the easiest DCV method
to congure. However, where VOCs, radon, or
other pollutants become excessive during unoc-
cupied times (with no ventilation), the FlexStat’s
Standard or Advanced DCV conguration is
recommended.
CO
2
Setpoint
0%
Space CO
2
CO
2
Maximum
DCV Signal
Component
to OAD
100%
Basic DCV Configuration
CO
2
Base
Outside Air
Damper
Position
Component
STANDARDDCV—When the BAC-13xxxx seings
are properly congured, this complies with
CATitle24,Section121(c). This would
also apply to a properly congured BAC-
12xxxx with a remote SAE-10xx CO
2
sensor.
Standard DCV, under most conditions, is
somewhat less energy ecient than Basic,
but it enhances IAQ.*
*NOTE: The CO
2
sensors in the BAC-13xxxx series
FlexStats (as well as properly congured
SAE-10xx CO
2
detectors) have been certied
to comply with CA Title 24, Section 121(c),
as well as sub-paragraph 4.F that species
accuracy will be maintained within
tolerance for a minimum of 5 years without
recalibration. Seethedatasheetformore
information.
CO
2
Setpoint
OA Full
OA Area
0%
Space CO
2
CO
2
Maximum
DCV Signal
Component
to OAD
100%
Standard DCV Configuration
CO
2
Base
Outside Air
Damper
Position
Component
“Basic” Signal
“Standard”
Signal
• ADVANCEDDCV—When the seings are
properly congured, this conguration complies
with CATitle24,Section121(c) and ASHRAE
Standard62.1-2007 and follows guidelines by
PortlandEnergyConservation,Inc.(PECI).
Although Advanced DCV is the most complex to
congure, it is more energy ecient than Stan-
dard while still optimizing IAQ.
OA Max
OA Full
OA Area
0%
Space CO
2
CO
2
Maximum
DCV Signal
Component
to OAD*
100%
Advanced DCV Configuration
CO
2
Base
Outside Air
Damper
Position
Component
*Under Normal
Vent Mode operation
(see Vent Mode description)
NOTE: The three graphs above show the DCV
component of the signal to the outside
air damper. Depending on the conditions
and the DCV conguration, the signal
to the damper might be controlled by
Minimum Position, Economizer Loop, or
other components. The maximum of these
component values is used, not the sum