Johnson Controls YORK YVAM 0350, Operation & Maintenance Manual

Page: 91 / 162

Table 89: Warning messages
Message Description
WARNING – EVAPORATOR –
LOW PRESSURE LIMIT
The Evaporator pressure has decreased to the Warning threshold. This threshold is fixed in
Water cooling applications. In Brine cooling applications, the threshold is a fixed amount
above the programmable safety shutdown threshold. The Safety threshold in Brine
applications is determined by the Brine solution and is determined by the YORK Factory.
While this condition is in effect, the chiller capacity control is in override to increase suction
pressure.
Warning threshold (psig) Reset threshold (psig)
Water Brine Water Brine
27.0 +2.0>Safety Setpoint 28.0 +3.0>Safety Setpoint
This message automatically clears and normal LCHLT capacity control restored when the
Evaporator pressure increases to the reset value.
WARNING – EXCESS SURGE
DETECTED
This message applies only if Surge Protection SHUTDOWN feature is Disabled. The Surge
Window Count has exceeded the Count Limit. Message can be manually cleared after the
Surge Window Count is less than or equal to the Count Limit, or the SHUTDOWN feature is
Enabled or the chiller is stopped. To clear message press WARNING RESET button on Home
Screen when logged in at OPERATOR (or higher) access level.
WARNING - LIQUID LEVEL
SETPOINT NOT ACHIEVED
The chiller is running and Refrigerant Level > (Refrigerant Level se15%) OR
Refrigerant Level < (Refrigerant Level setpoint -15%) for 10 continuous minutes. The
Warning is bypassed for the first 30 minutes of run to allow stabile operation to establish.
It is released when the chiller is not running or Refrigerant Level is within setpoint ±15%.
The message clears automatically.
WARNING - LOSS OF
SUBCOOLER LIQUID SEAL
The chiller is running greater than 30 minutes and the Subcooler Effectiveness value
decreased less than 0.400 (ADMIN programmable) at any drop leg refrigerant temperature
or increased greater than 1.50 (ADMIN programmable) when the drop leg refrigerant
temperature is at least 0.5°F below or any amount above the Entering Condenser Liquid
Temperature. The subcooler effectiveness is (Condenser Sat Temp - Drop leg refrigerant
temp)/(Cond Sat Temp - Entering Condenser Liquid Temp). To clear message, press
WARNING RESET button on Home Screen when logged in at OPERATOR (or higher) access
level.
WARNING – MBC – HIGH
AXIAL OSCILLATOR VOLTAGE
This manual reset warning is set when the internal oscillator that drives the axial position
sensor coil is overloaded for one continuous second. This is typically the result of an open
in the connection to the shaft position sensor. It could also be a failure of the MBC control
board. This message will clear when the voltage is normal and the WARNING RESET button
is pressed in OPERATOR (or higher) access mode.
WARNING – MBC – HIGH
RADIAL OSCILLATOR VOLTAGE
This manual reset warning is set when the internal oscillator that drives the radial position
sensor coil is overloaded for one continuous second. This is typically the result of an
opening in the connection to the shaft position sensor. It could also be a failure of the MBC
control board. This message will clear when the voltage is normal and the WARNING RESET
button is pressed in OPERATOR (or higher) access mode.
WARNING – MBC – CHECKSUM
CENTERING
This warning appears when the MBC Axial Centering process was never performed, or not
correctly realized internally. The centering process as found in the calibration section of
Form 160.88-M2 must be performed in ADMIN access. Then this message will clear when
the WARNING RESET button is pressed in OPERATOR (or higher) access mode.
WARNING – MBC – DSP
WATCHDOG
A software reboot has occurred on the control board due to processor problem, but reset
with the reboot. This message will clear when the WARNING RESET button is pressed in
OPERATOR (or higher) access mode.
WARNING – MBC – AMP
WATCHDOG
A software reboot has occurred on the amplifier (power) board due to processor problem,
but reset with the reboot. This message will clear when the WARNING RESET button is
pressed in OPERATOR (or higher) access mode.
WARNING – MBC – INTERNAL
ALARM
The MBC experienced an unsatisfactory condition detected internally to the control
system. This message will clear when the condition is resolved and the WARNING RESET
button is pressed in OPERATOR (or higher) access mode.
91 YVAM Control Center