York YPAL 050 User Manual

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94
JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
Sequence of Operation
“ B U I L D I N G   S TAT I C   P R E S S U R E   S E N S O R 
INSTALLED” 
– must be turned on using Parameter 85 
under the PROGRAM key on the Simplicity Elite control 
board or under the EQUIPMENT INSTALLATION tab 
in the Simplicity PC software package.
“BUILDING PRESSURE SETPOINT” must be 
programmed using Parameter 31 under the PROGRAM 
key on the Simplicity Elite control board or under the 
ECONOMIZER/EXHAUST tab in the Simplicity PC 
software package.
“EXHAUST VFD INSTALLED” must be turned 
on using Parameter 45 under the PROGRAM key 
on the Simplicity Elite control board or under the 
ECONOMIZER/EXHAUST tab in the Simplicity PC 
software package.
Sequence of Operation
When the building static pressure is 0.025” WC or more 
above the “BUILDING PRESSURE SETPOINT” the 
Simplicity Elite control sends a 2 to 10 volt DC signal 
to Exhaust Fan VFD, the output is at the “EXD+” and 
“EXD-“ terminals at the P14 connector, and enables 
the VFD operation through the output at the “EXH” 
terminal of the P13 connector.  When the exhaust fan 
fi rst comes on it will operate at the “Output Frequency 
Low Limit” that is programmed into the Exhaust 
Van VFD, regardless of the voltage output from the 
Simplicity Elite control.
When the building static pressure is 0.025” WC or 
more below the “BUILDING PRESSURE SETPOINT” 
the Simplicity Elite control lowers the 2 – 10 volt DC 
output to the Exhaust Fan VFD.  When the output is 
equal to or below 2 volts, the Exhaust Fan VFD enable 
input is removed.
PRE-OCCUPANCY PURGE
This feature allows the blower to come on and the 
economizer damper to open during the unoccupied 
period to purge the air within the conditioned space.
In order to use this feature the following parameters 
must be programmed:
“PRE-OCCUPANCY PURGE ENABLE” – must be 
enabled using the SYSTEM OPTIONS tab in the 
Simplicity PC software package.
“PRE-OCCUPANCY PURGE TIME (hours of day)” 
– must be programmed using the SYSTEM OPTIONS 
tab in the Simplicity PC software package.
“PRE-OCCUPANCY PURGE TIME (minutes of day)” 
– must be programmed using the SYSTEM OPTIONS 
tab in the Simplicity PC software package.
Criteria for Operation
  The feature will only work when the internal 
scheduling feature is being used to determine 
occupied and unoccupied periods.
  The feature will only work on a day that has a 
occupied period scheduled.
Sequence of Operation
 The 
programmed 
“PRE-OCCUPANCY PURGE 
TIME” is length of the pre-purge prior to the 
start of the occupancy period.  For example if 
the “PRE-OCCUPANCY PURGE TIME (hours 
of day)”
 is set for 1, the “PRE-OCCUPANCY 
PURGE TIME (minutes of day)”
 is set to 30 and 
the occupancy start time is 8:00 AM pre-purge 
would start at 6:30 AM and operate until 8:00 
AM.
  While in the pre-purge mode the Simplicity Elite 
control will turn on the fan and modulate the 
outdoor air damper to 100% as long as the supply 
air temperature is between 45.0° F and 90.0° F.
  If the supply air temperature drops below 45.0° F 
the control will modulate the outdoor air damper 
closed until the supply air temperature rises above 
50.0° F.
  If the supply air temperature rises above 90.0° F 
the control will modulate the outdoor air damper 
closed unit the supply air temperature falls below 
85.0° F.