York YPAL 060 User Manual

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JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
Service
LIGHT EMITTING DIODE
The light emitting diode (LED) installed on the Unit 
Controller is used to indicate the functionality of the 
Unit Controller and the unit.  Normal operation is 
indicated by the LED fl ashing ON and OFF at a rate 
of one-second.  A one-second ON followed by a one-
second OFF fl ash.  This means there are no active fl ash 
codes, faults or clock-outs.  However there may be faults 
recorded in the history buffer. 
A fl ash rate of 250 ms ON and OFF indicates a current 
alarm is present.  The alarm code number will also be 
fl ashing on the four-digit character display.  See Table 
8-9 for a description of each of the alarm codes.
If the LED is constantly on (does not fl ash), the board 
has failed and must be replaced.  If the LED is OFF 
this indicates no power to the board or a board failure.  
Two fl ashes ON, then two-seconds OFF indicates the 
control is timing out on an Anti-Cycle-Delay (ASCD).  
To bypass the ASCD timer depress the TEST/UP button 
3 times within 5 seconds.
FAULTS AND LOCKOUTS
ALARM CODES
An active alarm is represented by a fl ashing alarm code 
numeral.  There are 43 alarms in all.  Not all the alarms 
are critical enough to shut down the system.  Some 
alarms fl ag the problem to bring it to the attention of 
the operator or technician while allowing the system to 
continue to operate.
The display fl ashes the current or most recent code 
and contains the last fi ve failures as well.  To recall the 
last fi ve failures from the most recent to the oldest of 
the fi ve, press the “Alarm/Change” button once and 
each code is displayed for two seconds.  Each failure 
code is numbered 1 to 5 and the number is shown in 
the two-digit character display located above the four-
digit display.
The current and last fi ve alarms can also be views under 
the “ALARM” tab using the Simplicity PC software.
A unit lockout can be reset in three ways:
• 
Removing the 24 VAC supply to the Unit Con-
troller.
• 
Press the TEST/UP button twice in 5 seconds.
• 
By a communicated command.