York YPAL 060 User Manual

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JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
Sequence of Operation
Constant Volume
The following conditions must be met in order for 
Economizer Loading to function:
  The outdoor air temperature must be greater than 
the return air temperature.
  Economizer must be installed but not active.
  A call for fi rst stage compressor operation only
  The unit must be confi gured as a Constant Volume 
unit.
  The unit must be in an occupied or unoccupied 
cooling mode.
The sequence of operation is as follows:
  When the supply air temperature is 0.1° F less 
than the “SUPPLY AIR TEMP LIMIT COOLING 
SETPOINT”
 the economizer damper will start to 
open.
  If the economizer damper opens 100% and the 
supply air temperature is still 0.1° F less than 
the  “SUPPLY AIR TEMP LIMIT COOLING 
SETPOINT”
 the Simplicity Control will turn off 
the compressor per the Excessive SAT sequence 
and close the economizer damper to its minimum 
position.
  When the supply air temperature is between 
“SUPPLY AIR TEMP LIMIT COOLING 
SETPOINT”
 and the “SUPPLY AIR TEMP 
LIMIT COOLING SETPOINT”
 plus 5.0° F the 
economizer damper movement will stop and 
maintain the current position.
  When the supply air temperature is equal to 5.1° 
F or more above the “SUPPLY AIR TEMP LIMIT 
COOLING SETPOINT”
 the economizer damper 
will close back to its minimum position.
Variable Air Volume
The following conditions must be met in order for 
Economizer Loading to function:
  The outdoor air temperature must be greater than 
the return air temperature.
  Economizer must be installed but not active.
  A call for fi rst stage compressor operation only.
  The unit must be confi gured as a Variable Air 
Volume unit.
  The unit must be in an occupied or unoccupied 
cooling mode.
The sequence of operation is as follows:
  When the supply air temperature is 5.1° F less 
than the “VAV COOLING SUPPLY TEMP UP-
PER SAT SETPOINT”
 or “VAV COOLING 
SUPPLY AIR TEMP LOWER SETPOINT”
 the 
economizer damper will start to open.
  If the economizer damper opens 100% and the 
supply air temperature is still 5.1° F less than 
the  “VAV COOLING SUPPLY TEMP UPPER 
SAT SETPOINT” 
or “VAV COOLING SUPPLY 
AIR TEMP LOWER SETPOINT” 
the Simplicity 
Control will turn off the compressor close the 
economizer damper to its minimum position.
  When the supply air temperature is between 
“VAV COOLING SUPPLY TEMP UPPER SAT 
SETPOINT”
 and the “VAV COOLING SUPPLY 
TEMP UPPER SAT SETPOINT”
 plus 5.0° F 
the economizer damper movement will stop and 
maintain the current position.
  When the supply air temperature is between 
“VAV COOLING SUPPLY TEMP LOWER SAT 
SETPOINT”
 and the “VAV COOLING SUPPLY 
TEMP LOWER SAT SETPOINT”
 plus 7.0° F 
the economizer damper movement will stop and 
maintain the current position.
  When the supply air temperature is equal to 5.1° 
F or more above the “VAV COOLING SUPPLY 
TEMP UPPER SAT SETPOINT” 
and 5 minutes 
has expired since the economizer damper started 
to open, the economizer damper will close back 
to its minimum position and a second compressor 
will come on.
  When the supply air temperature is equal to 7.1° 
F or more above the “VAV COOLING SUPPLY 
TEMP LOWER SAT SETPOINT”
 and 5 minutes 
has expired since the economizer damper started 
to open, the economizer damper will close back 
to its minimum position and a second compressor 
will come on.