Displayed Alarm
Message
Recognition
Possible Cause
Possible Remedy
Trouble Shooting
72 Chiller Air-cooled Screw
• Charge additional refrigerant
• Test/Repair as necessary and
charge additional refrigerant
• Adjust low pressure switch setting
• Repair or replace Low pressure
switch
• Repair or replace controller
• Trip of low pressure
switch
• Insufficient refrigerant
• Refrigerant leakage
• Low pressure switch setting too
high
• Low pressure switch error
• Controller DI point error
Pressure Alarm
• Replace oil dryer
• Replace oil service valve
• Repair or replace oil flow switch
• Repair or replace controller
• Supplement oil
• Oil flow switch input
(switch off) 120 sec-
ond after the compres-
sor run
• Oil dryer clogged
• Oil service valve error or closed
• Oil flow switch error
• Controller DI error
• Shortage of oil
• Replace oil level switch
• Repair or replace controller
• Supplement oil
• Oil level switch input
(switch off) 120 sec-
ond after the compres-
sor run
• Oil level switch error
• Controller DI point error
• Shortage of oil
System Oil Alarm
• Replace M1 contactor
• Check voltage, check condenser
fan motor, clean heat exchanger,
repair overload relay, repair or
replace compressor
• Repair or replace controller
• M1 magnetic contactor
contact input or over-
load relay contact input
(switch off) after the
compressor run
• Malfunction of M1
• Compressor overload
• Controller DI or DO point error
M1 Contactor
Alarm
• Replace M2 contactor
• Repair or replace controller
• M2 magnetic contactor
contact input after the
compressor run
• Malfunction of M2
• Controller DI or DO point error
M2 Contactor
Alarm