91
JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
5
Defi nitions
“IAQ SENSOR RANGE” –This establishes the span the
Simplicity Elite control uses in PPM. 0 PPM would be
equal to a 0 volts input to the Simplicity Elite control,
“IAQ SENSOR RANGE” would be equal to 10 volts
input to the Simplicity Elite control. The “IAQ SENSOR
RANGE” must match the PPM range of the sensor
installed in the conditioned space.
“IAQ SETPOINT” – This is the conditioned space CO2
level the Simplicity Elite control is trying to maintain.
“MAXIMUM IAQ ECONOMIZER POSITION” – This
is the maximum damper position the Simplicity Elite
control will allow the damper to open while in a Demand
Ventilation mode no matter how great a differential is
between the conditioned space CO2 level and the “IAQ
SETPOINT”.
Sequence of Operation
The damper will open to the programmed
“ECONOMIZER MINIMUM POSITION” whenever
the following conditions are met:
• The unit is in the occupied mode.
• There must be a 24-volt output from the Simplic-
ity Elite control to the supply fan control circuit.
The output is contained at the “FAN” terminal
of connector P13 on the Simplicity Elite control
board.
• When the economizer becomes active the position
of the dampers are controlled by the Economizer
PI logic which could move the dampers beyond
the “ECONOMIZER MINIMUM POSITION”;
however, the Economizer PI logic can never
close the dampers less then the “ECONOMIZER
MINIMUM POSITION”.
If the above criteria are met, the Simplicity Elite control
will then monitor the CO2 level in the conditioned space
and vary the position of the outdoor air damper between
the “ECONOMIZER MINIMUM POSITION” and the
“MAXIMUM IAQ ECONOMIZER POSITION” based
on the following:
• The Simplicity Elite control will try to maintain
the CO2 level in the conditioned space to +/- 100
PPM of the “IAQ SETPOINT”.
• If the CO2 level in the conditioned space is
greater then the “IAQ SETPOINT” + 100 PPM
the outdoor air damper will open, but never more
than the “MAXIMUM IAQ ECONOMIZER PO-
SITION”.
• If the CO2 level in the conditioned space is less
then the “IAQ SETPOINT” - 100 PPM the out-
door air damper will close, but never less then
the “ECONOMIZER MINIMUM POSITION”.
VENTILATION LOW AMBIENT MINIMUM POSITION
RESET
This feature allows the control to reset the minimum
ventilation set point to a lower value when the outdoor
temperature is cold. This assists in keeper the supply air
temperature from dropping because of a fi xed ventilation
requirement when the outdoor temperature drops.
To use this feature the following parameters need to be
programmed:
“LOW AMBIENT ECONOMIZER SETPOINT” – this
parameter is programmed under the ECONOMIZER/
EXHAUST tab in the Simplicity PC software
package.
“LOW AMBIENT ECONOMIZER MINIMUM
POSITION” – this parameter is programmed under
the ECONOMIZER/EXHAUST tab in the Simplicity
PC software package.
Sequence of Operation
When “LOW AMBIENT ECONOMIZER SETPOINT”
is programmed to 0 the feature is disabled. To
use this feature programmed this parameter to the
outdoor temperature at which you want the Simplicity
Elite control to switch to the “LOW AMBIENT
“ECONOMIZER MINIMUM POSITION”. This
parameter can be programmed between 0 and 60.0° F.
The parameter “LOW AMBIENT ECONOMIZER
MINIMUM POSITION” needs to be programmed to the
minimum position of the damper when the temperature
is below the “LOW AMBIENT ECONOMIZER
SETPOINT”. This parameter can be programmed
between 0 and 99%. It would normally be programmed
less then the “ECONOMIZER MINIMUM POSITION”
parameter.