York YPAL 051 User Manual

Page of 168
82
JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
Sequence of Operation
Sequence of Operation
Tables 5-4 thru 5-6 use the following defi nitions:
  SAT COMFORT ZONE – the temperature be-
tween the “COMFORT VENTILATION LOWER 
SETPOINT”
 minus 1.0° F and the “COMFORT 
VENTILATION UPPER SETPOINT”
 plus 1.0° 
F.
  OAT COMFORT ZONE - the temperature be-
tween the “COMFORT VENTILATION LOWER 
SETPOINT”
 and the “COMFORT VENTILA-
TION UPPER SETPOINT”.
 
 OAT 
– 
Outdoor 
Air 
Temperature.
 SAT 
– 
Supply 
Air 
Temperature.
  ECON OPERATION – Economizer damper will 
open to BRING SAT into the SAT COMFORT 
ZONE.
Conditions of Operation
  In order for compressor operation “COMFORT 
VENTILATION FOR COOLING ENABLED” 
must be enabled.
  In order for heat stages to operate “COMFORT 
VENTILATION FOR HEATING ENABLED” 
must be enabled.
  Economizer operation will occur with either, or 
both, “COMFORT VENTILATION FOR COOL-
ING ENABLED” 
or  “COMFORT VENTILA-
TION FOR HEATING ENABLED” 
enabled.
EXCESSIVE SAT (SUPPLY AIR TEMPERATURE) 
CONTROL
This feature is only available on Constant Volume 
units.  On a Constant Volume unit, the compressors 
and heat stages are control by the space temperature 
only, either by thermostat or zone sensor.  As long as 
the room device is calling for cooling or heating the 
compressors or heating section does not control the 
actual temperature of the supply air leaving the unit.  
The enabling of this feature adds a means to prevent low 
or high supply air temperatures from being delivered to 
the conditioned space.  
Cooling
T h e   f o l l o w i n g   S y s t e m   P a r a m e t e r s   m u s t   b e 
programmed:
“SUPPLY AIR TEMP LIMIT FOR COOLING 
ENABLED”
- must be enabled using Parameter 14 under 
the PROGRAM key on the Simplicity control board or 
under the COOLING SETUP tab in the Simplicity PC 
software package.
“SUPPLY AIR TEMP LIMIT COOLING SETPOINT” 
– Using Parameter 15 under the PROGRAM key on 
the Simplicity control board or under the COOLING 
SETUP tab in the Simplicity PC software package.
If a single compressor is energized the control will 
monitor the supply air temperature and respond as 
follows:
TABLE 5-6  HEAT STAGE ON WHEN SPACE INPUT SATISFIED
OAT VS OAT COMFORT ZONE
SAT VS SAT COMFORT ZONE
ECON OPERATION
HEAT STAGE
COMP STAGE
BELOW
ABOVE
OPEN
LEAVE ON*
-
BELOW
BELOW
-
LEAVE ON
-
BELOW
WITHIN
-
LEAVE ON
-
ABOVE
ABOVE
-
TURN OFF
TURN ON
ABOVE
BELOW
OPEN
TURN OFF
-
ABOVE WITHIN
-
TURN 
OFF
-
WITHIN
ABOVE
OPEN
TURN OFF
-
WITHIN
BELOW
OPEN
TURN OFF
-
WITHIN
WITHIN
-
TURN OFF
-