JOHNSON CONTROLS
52
FORM 160.81-NOM1
ISSUE DATE: 10/3/2020
SECTION 3 – OPERATION
NEED FOR MAINTENANCE OR SERVICE
If the system is malfunctioning in any manner, or the
unit is stopped by one of the safety controls, please call
the nearest Johnson Controls Service Office. Failure to
report constant troubles could damage the unit and in-
crease the cost of repairs considerably.
NORMAL SAFETY SHUTDOWN AND REPAIRS
Normal and safety system shutdowns have been built
into the unit to protect it from damage during certain
operating conditions. Therefore, it should be under-
stood that at certain pressures and temperatures the
system will be stopped automatically by controls that
respond to high temperatures, low temperatures, or low
and high pressures, etc.
SAFETY SHUTDOWNS
• Evaporator – Low Pressure
• Evaporator – Low Pressure – Smart Freeze
• Evaporator – Transducer or Leaving Liquid Probe
• Evaporator – Transducer or Temperature Sensor
• Condenser – High Pressure Contacts Open
• Condenser – High Pressure
• Condenser – Pressure Transducer Out of Range
• Auxiliary Safety – Contacts Closed
• Discharge – High Pressure
• Discharge – High Temperature
• Discharge – Low Temperature
• Oil – High Temperature
•
Oil – Low Differential Pressure
• Oil or Condenser Transducer Error
• Oil – Clogged Filter
• Oil – High Pressure
• Control Panel – Power Failure
• Motor or Starter – Current Imbalance
• Motor or Starter – Incorrect Compressor Rotation
Detected
• Motor – High Motor Winding Temperature
Mod “B” Solid State Starter
• LCSSS Shutdown – Requesting Fault Data
• LCSSS – High Instantaneous Current
• LCSSS – High Phase Heatsink Temperature Run-
ning
• LCSSS – 105% Motor Current Overload
• LCSSS – Phase Shorted SCR
• LCSSS – Open SCR
• LCSSS Phase Rotation
CYCLING SHUTDOWNS
• Multi-Unit Cycling – Contacts Open
• System Cycling – Contacts Open
• Control Panel – Power Failure
• Leaving Chilled Liquid – Low Temperature
• Leaving Chilled Liquid – Flow Switch Open
• Condenser – Flow Switch Open
• Motor Controller – Contacts Open
• Motor Controller – Loss of Current \ Power Fault
• Control Panel – Schedule
Mod “B” Solid State Starter
• LCSSS – Initialization Failed
• LCSSS – Serial Communications
• LCSSS Shutdown – Requesting Fault Data
• LCSSS – Stop Contacts Open
• LCSSS – Power Fault
• LCSSS – Low Phase Temperature Sensor
• LCSSS – Run Signal
• LCSSS – Invalid Current Scale Selection
• LCSSS – Phase Locked Loop
• LCSSS – Low Supply Line Voltage
• LCSSS – High Supply Line Voltage
• LCSSS – Logic Board Processor
• LCSSS – Logic Board Power Supply
• LCSSS – Phase Loss
