York YPAL 051 User Manual

JOHNSON CONTROLS

FORM 100.50-NOM6 (1207)

The Simplicity Control cannot operate unoccupied 
cooling with this method of control.

The following parameters must be programmed into 

the Simplicity Control:

•  “VAV OCCUPIED HEATING ENABLED” 

– This must be turned on using Parameter 26 
under the PROGRAM key on the Simplicity 
control board or under the HEATING SETUP 
tab in the Simplicity PC software package.

• “MORNING 

WARM-UP/ 

VAV 

RETURN 

AIR 

TEMP SETPOINT” – using Parameter 29 under 
the PROGRAM key on the Simplicity control 
board or under the HEATING SETUP tab in the 
Simplicity PC software package.

•  “VAV OCCUPIED HEATING SETPOINT” – us-

ing Parameter 27 under the PROGRAM key on 
the Simplicity control board or under the HEAT-
ING SETUP tab in the Simplicity PC software 
package.

•  “SPACE SENSOR FAULT OVERRIDE EN-

ABLED” must be turned on – using Parameter 
8 under the PROGRAM key on the Simplicity 
control board or under the SYSTEMS OPTIONS 
tab in the Simplicity PC software package.

The unit will initiate Occupied Heating when the 
following criteria are met:

•  The return air temperature is 2.0° F less than the 

“VAV OCCUPIED HEATING SETPOINT”.

•  The return air temperature is 0.1° F below the 

“MORNING WARM UP / VAV RETURN AIR 
TEMP SETPOINT”.

The “VAV OCCUPIED HEATING SETPOINT” should 
always be set below the “MORNING WARM UP RAT 
SETPOINT”.

The unit will terminate Occupied Heating when:

•  The return air temperature is equal to the 

“MORNING WARM UP RAT SETPOINT”.

The Simplicity Control cannot operate unoccupied 
heating with this method of control.

 
A call for the operation of compressor 1A or 1B will 
close an output at terminal CF1 of the P13 connector. 
This 24 VAC output energizes the 6M contactor and 
turns on condenser fan 1. This 24 VAC output is also 
sent to pressure switch PS3. If the discharge pressure 
rises above 360 psig the PS3 switch closes and energizes 
the 7M contactor. The 7M contactor then energizes 
condenser fan 2. If the discharge pressure decreases 
below 300 psig the PS3 switch opens and de-energizes 
condenser fan 2. 
 
A call for the operation of compressor 2A or 2B will 
close an output at terminal CF2 of the P13 connector. 
This 24 VAC output energizes the 8M contactor and 
turns on condenser fan 3. This 24 VAC output is also 
sent to pressure switch PS4. If the discharge pressure 
rises above 360 psig the PS4 switch closes and energizes 
the 9M contactor. The 9M contactor then energizes 
condenser fan 4. If the discharge pressure decreases 
below 300 psig the PS4 switch opens and de-energizes 
condenser fan 4. 
 

 
This feature prevents operation of mechanical cooling 
when the outdoor temperature is below this set point. 

• 

“OUTDOOR AIR TEMP COOLING LOCKOUT” 
- this parameter can be set using the COOLING 
SETUP tab in the Simplicity PC software pack-
age. This parameter should never be programmed 
less then 45.0º F 

 
Sequence of Operation 

• 

If the outdoor temperature is 1.0º F below the 
“OUTDOOR AIR TEMP COOLING LOCK-
OUT” the Simplicity Elite control will prevent 
compressor operation. 

• 

When the outdoor temperature is 1.0º F above 
the “OUTDOOR AIR TEMP COOLING LOCK-
OUT” compressor operation will be permitted.