Johnson Controls YORK YMC2 Operation And Maintenance Manual

Cycling shutdown messages
For cycling shutdown messages, the chiller will automatically restart when the cycling condition
clears.
Table 99: Cycling shutdown messages
Message Description
CHILLED LIQUID –
FLOW SWITCH OPEN
The Chilled Liquid Flow Switch has remained open for 5 continuous
seconds while the chiller was running, in soft shutdown, or at least 45
seconds after MBC startup is initiated. The chiller will automatically
restart when the flow switch closes or the fault will clear if the chiller is
run command is ceased.
CONDENSER – FLOW
SWITCH OPEN
The Condenser water flow switch has remained open for 5 continuous
seconds while the chiller was running, in soft shutdown, or at least 45
seconds after MBC startup is initiated. The chiller will automatically
restart when the flow switch closes or the fault will clear if the chiller is
run command is ceased.
CONDENSER -FREEZE
THREAT-FLOW SWITCH
OPEN
This fault is set when all of the following are true:
• Chiller State is Stopped
• Saturated Condenser Temperature < 35.0°F (1.6°C)
• Condenser Flow Switch is Open for 1 minute or longer
It is released when any of the following are true:
• Chiller State is not Stopped
• Saturated Condenser Temperature > 40.0°F (4.4°C)
• Condenser Flow Switch is Closed
CONTROL PANEL –
LOSS OF CONTROL
VOLTAGE
The line power input signal at I/O board TB3-81 was low for 1 second
continuous. This signal is used to determine when the digital inputs
are affected by a line power loss versus an actual condition for their
devices. This fault is not expected on an actual loss of microboard
power from the critical load bus, because the processor will be off
before the fault delay. This message can indicate a Cycling (auto-restart
after power failure) or Safety (manual restart after power failure)
shutdown, depending upon control center configuration.
CONTROL PANEL –
POWER FAILURE
A Control Power failure has occurred. If the power failure occurred
while the chiller was running, it will automatically restart when power
is restored. This message can indicate a Cycling (auto-restart after
power failure) or Safety (manual restart after power failure) shutdown,
depending upon control center configuration. It indicates a cycling
shutdown when displayed in orange characters; Safety shutdown when
displayed in red characters. The control center is configured for auto-
restart or manual restart after power failure by a qualified service
technician following instructions in YORK YMC
2
Service Manual (Form
160.84-M2).
CONTROL PANEL –
SCHEDULE
The programmed Daily Schedule Setpoint has shutdown the chiller. If
this occurs while the chiller is running, a Soft Shutdown is performed.
The chiller will automatically restart at the next scheduled start time.
YMC
2
Mod B with OptiView Control Center
102

Johnson Controls YORK YMC2 Specifications

General

Brand	Johnson Controls
Model	YORK YMC2
Category	Chiller
Language	English