Specifications

28
TROUBLESHOOTING GUIDE.
Trouble, Alarm Codes Causes Corrective Actions
Pressure transducer alarm
PRSA
• Bad transducer
• Out of range
• Loose wire
• Wrong hook-up
• Replace the pressure transducer
• Turn off power for a few seconds, turn back on
• Toghten the connections
• Wire correctly
Outlet sensor TS2 fails
STSA
• Mechanical damage
• Connection wire loose
• Overheated
• Out of range
• Replace the sensor
• Tighten the connection wires
• When brazing suction line, take out the sensor
• Install the sensor after brazing
Room sensor TS3 fails
ATSA
• Mechanical damage
• Connection wire loose
• Overheated
• Out of range
• Tighten the connection wires on the controller
terminal
• The room sensor can be replaced by surface sensor
Coil/defrost sensor TS1 fails
CTSA
• Mechanical damage
• Loose connection wire
• Overheated
• Out of range
• Tighten the connection wires on the controller
terminal
• Let the sensor cool down to application temperature
range: –50
o
F to +103
o
F
• Replace failed sensor
Aux sensor fails (if provided)
T4SA
• Mechanical damage
• Loose connection wire
• Overheated
• Out of range
• Tighten the connection wires on the controller
terminal
• Let the sensor cool down to application temperature
range: –50
o
F to +103
o
F
• Replace failed sensor
Low superheat
LOSH
• Superheat setting too low
• Wrong locations of TS2
• Sensors may be loose
• Uneven feeding of coil circuits
• Overcharge of refrigerant
Defective electric expansion valve (EEV)
• Compressor stops
• Change to correct set point
• Make sure the distributor is feeding each circuit
evenly
• Insulate the sensors with foam tape
• Use correct refrigerant charge
• Check EEV wiring
• Replace defective EEV
• Check compressor
High room temperature
HITA
• Insufficient refrigeration
• Heat load too large
• Compressor fails or high pressure cuts out
• Evaporator fans may not run
• Door open for too long
• Coil iced-up
• Check system design to select a sufficient system
• Replace failed compressor
• Fix the evaporator fans
• Keep the cold room door closed during refrigeration
• Check possible air leak through the walls of cold
room
Low room temperature
LOTA
• Inproper low temp setpoint
• Over designed system
• Change low temp set point
• Re-select the system
Low pressure alarm
LPRA
• Refrigerant leak
• Bad transducer
• Fix leak
• Replace pressure transducer
Digital Input 1
XTA1
• Incorrect digital input MODE
• Mechanical damage
• Loose connection wire
• Out of range
• Correct the digital input MODE parameter
• Tighten the connection wires on the controller
terminal
• Replace failed sensor/switch/relay
Digital Input 2
XTA2
• Incorrect digital input MODE
• Mechanical damage
• Loose connection wire
• Out of range
• Correct the digital input MODE parameter
• Tighten the connection wires on the controller
terminal
• Replace failed sensor/switch/relay
Digital Input 3
XTA3
• Incorrect digital input MODE
• Mechanical damage
• Loose connection wire
• Out of range
• Correct the digital input MODE parameter
• Tighten the connection wires on the controller
terminal
• Replace failed sensor/switch/relay
Door Alarm
DROA
• Door are open
• Incorrect parameter
• Bad door switch
• Close door tightly
• Declare the correct parameter relay (open/close)
• Change the door switch
Communication
COMA
• Loose RJ-45 coonection
• Failed communication port
• Replace connector
• Change a new controller board