HRX-MM-N007
Chapter 3 Alarm Indication and Troubleshooting
HRS Series 3.3 Troubleshooting
AL19: Communication error
<Detection method> This alarm goes off when no request messages have been received from the host
computer for a specific period of time.
Check with referring to
"Chapter 6 Communication
Alarm Function" in Operation
Manual Communication
Function.
N
Y
1.
Check the main board after
replacement.
Has the set value
been changed from the
default setting?
Communication errorAL19
No alarm
generated.
The alarm is
generated.
Complete.
Replace the communication
board.
See section "4.5.16
Replacement of main board
& communication board".
1. Check the main board after replacement.
Replace the main board with a new one. (See section "4.5.16 Replacement of main board &
communication board")
After replacement, check if the alarm goes off again.
AL20: Memory error
<Detection method> This alarm goes off when the written data to the CPU and the read data do not
match.
1.
After stopping the power
supply, does the same alarm go off
again when the chiller is
restarted?
Please contact SMC or
distributor.
N
Y
Memory errorAL20
Replace the main board.
See section "4.5.16
Replacement of main board
& communication board".
1. After stopping power supply, check for the same alarm goes off again when the
chiller is re-started.
After stopping power supply (by tuning off the power supply switch on the Thermo-Chiller), check if
the same alarm goes off again when the Thermo-Chiller is restarted.