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507964-01 9/2019
C-Economizer Operation
Note - Use indicating lights on Unit Controller to determine
thermostat demand.
See table 32 for economizer operation with a standard
two-stage thermostat
D-Damper Minimum Position Setting
Use the following menu path to modify the minimum damper
positions for both high and low operations.
SETUP > TEST & BALANCE > DAMPER > MIN
DAMPER POSITION BLOWER ON HIGH = .%
SETUP > TEST & BALANCE > DAMPER > MIN
DAMPER POSITION BLOWER ON LOW = .%
Table 33 shows economizer operation with an energy
management system which uses a global sensor.
Both tables show the occupied and unoccupied time period.
The occupied time period is determined by the thermostat
or energy management system.
Table 34 shows economizer operation in zone sensor
mode.
E-IAQ Damper Operation
The Unit Controller has a 0-10VDC IAQ input for a
standard 0-2000ppm CO
2
sensor. The economizer starts
opening at a CO
2
level of 700 ppm (default) and reaches
full open at a CO
2
level of 1200ppm. Adjustments may be
made to the indoor air quality parameters to alter operation
or meet required specifications (parameters 117 through
119). Go to SETUP > TEST & BALANCE > DAMPER >
VENTILATION OPTIONS.
If the economizer is operating in the free cooling mode and
the IAQ sensor demands more fresh air, the IAQ demand
will override the free cooling demand to open the dampers
further or to keep them open.
The IAQ function is not energized during the unoccupied or
night time period.
TABLE 32
ECONOMIZER OPERATION - Standard Two-Stage Thermostat (Default Option)
THERMOSTAT DEMAND
DAMPER POSITION UNOCC.
DAMPER POSITION OCCUPIED
MECHANICAL COOLING
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
OUTDOOR AIR IS NOT SUITABLE FOR FREE COOLING
OFF
CLOSED
CLOSED
NO
G
CLOSED
MINIMUM
NO
Y1
CLOSED
MINIMUM
STAGE 1
Y2
CLOSED
MINIMUM
STAGES 1 AND 2
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
OUTDOOR AIR IS SUITABLE FOR FREE COOLING
OFF
CLOSED
CLOSED
NO
G
CLOSED
MINIMUM
NO
Y1
MODULATING
MODULATING
NO
Y2
MODULATING
MODULATING (1)
STAGE 1
Note - Modulating dampers adjust to control supply air (RT6) to 55_F (13_C). (1) The Unit Controller goes into a “cool down” or “warm-up” mode when the
occupied time period starts. (2) Units with two-stage compressor operation will operate only stage 1 with a Y2 demand.
TABLE 33
ECONOMIZER OPERATION WITH GLOBAL SENSING - Energy Management System (Default Option)
THERMOSTAT DEMAND
DAMPER POSITION UNOCC.
DAMPER POSITION OCCUPIED
MECHANICAL COOLING
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
GLOBAL INPUT OFF
OFF
CLOSED
CLOSED
NO
G
CLOSED
MINIMUM
NO
Y1
CLOSED
MINIMUM
STAGE 1
Y2
CLOSED
MINIMUM
STAGES 1 AND 2
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
GLOBAL INPUT ON
OFF
MODULATING
MODULATING
NO
G
MODULATING
MODULATING
NO
Y1
MODULATING
MODULATING
STAGE 1
Y2
MODULATING
MODULATING (1)
STAGES 1 AND 2 (2)
Note - Modulating dampers adjust to control supply air (RT6) to 55_F (13_C). (1) The Unit Controller goes into a “cool down” or “warm-up” mode when the
occupied time period starts. (2) Units with two-stage compressor operation will operate only stage 1 with a Y2 demand (default).
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