York MILLENNIUM, Operating Instructions Manual

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YORK INTERNATIONAL
The Discharge Pressure Cutout is a software cutout in
the microprocessor and is backed-up by a mechanical
high pressure cutout switch located in the refrigerant
circuit. It assures that the system pressure does not
exceed safe working limits. The system will shutdown
when the programmable cutout is exceeded and will
be allowed to restart when the discharge pressure falls
below the cutout. Optional Discharge transducers
must be installed for this function to operate.
The Suction Pressure Cutout is a software cutout that
protects the chiller from an evaporator freeze-up should
the system attempt to run with a low refrigerant charge
or a restriction in the refrigerant circuit. This function
will not operate unless Suction Pressure Transducers
are installed, which are optional on some models.
This message is displayed when the system has locked
out due to either the compressor motor protector, mo-
tor overload or high pressure cutout opening.
These will be displayed only if a system is locked out
and the lockout fault information is not available, or
the ON button is pressed on the RCC while a system is
locked out on a fault.
The Under Voltage Safety assures that the system is
not operated at voltages where malfunction of the mi-
croprocessor could result in system damage. When the
115VAC to the micropanel drops below a specific level,
a unit fault is initiated to safely shut down the unit.
Restart is allowed after the unit is fully powered again
and the anti-recycle timers have finished counting down.
The Low Battery Warning can only occur at unit power-
up. When the chiller micropanel is suppled power, the
RTC battery is checked on the chiller microboard. If a
low battery is found, all programmed setpoints, pro-
gram values, options, time, schedule, and history buff-
ers will be lost. These values will all be reset to their
default values which may not be the desired operating
values. Once a faulty battery is detected, the unit will
be prevented from running until the PROGRAM key is
pressed on the chiller keypad. Once PROGRAM is
pressed, the anti-recycle timers will be set to the pro-
grammed anti-recycle time to allow the operator time
to check setpoints, program values, and options.
• System Faults
Following are all the system fault messages. Note that
any message can be displayed for any system. Single
system units will blank the second line of the display.
S Y S 1 H I G H D S C H P R E S
S Y S 2 H I G H D S C H P R E S
S Y S 1 L O W S U C T P R E S
S Y S 2 L O W S U C T P R E S
S Y S 1 M P / H P C O F A U L T
S Y S 2 M P / H P C O F A U L T
S Y S 1 L O C K E D O U T
S Y S 2 L O C K E D O U T
L O W B A T T E R Y ! !
C H E C K P R O G / S E T P / T I M E
U N I T F A U L T :
1 1 5 V A C U N D E R V O L T A G E
Status Messages