York YPAL 050 User Manual

JOHNSON CONTROLS

FORM 100.50-NOM6 (1207)

“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”.

T h e   d a m p e r   w i l l   o p e n   t o   t h e   p r o g r a m m e d 
“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”.

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.

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.