HRX-MM-N007
Chapter 3 Alarm Indication and Troubleshooting
3.3 Troubleshooting
HRS Series
3-30
AL04: Circulating fluid discharge temp. drop
<Detection method> This alarm goes off when the temperature sensor for the circulating fluid (for
discharge) detects 1
o
C or less (can be changed).
Has temperature
been changed from the
default (1
o
C)?
Does the alarm go
off when heat load
fluctuates?
Doe the alarm go
off right after the Thermo-Chiller
starts/stops?
Y
N
Y
Y
N
N
Use Alarm Customizing
Function.
(Refer to "Setting of
temperature alarm
monitoring method and alarm
generation timing" shown in
Operation Manual.)
1.
Is the cooling load
larger than the heating capacity
being applied to the
Thermo-Chiller?
This system cannot be used.
Circulating fluid discharge
temp. drop
AL04
Is AL22 being generated?
Y
N
AL22: Circulating fluid
discharge temp. sensor
failure
2.
Check the circulating
fluid temperature sensor
(PT1).
3.
Check the circulating fluid
temperature sensor (PT1) after
it is replaced.
4.
Is the flow rate of the
circulating fluid less
than 5 L/min?
5.
Check the pump
performance.
Normal
Error
Normal
Error
Y
N
Connect a by-pass piping.
Normal
Error
6.
After stopping the power
supply, the same alarm goes off
again when the chiller
is restarted.
Please contact SMC or
distributor.
N
Y
Y
N
Are other alarms being
generated simultaneously?
Y
N
Check the troubleshooting
that is corresponding to the
alarm number that is being
generated.
Replace the main board.
See section "4.5.16
Replacement of main board
& communication board".
Replace the pump.
See section "4.5.3
Replacement of pump (For
standard pump)" and
4.5.4 Replacement of high
pressure pump
Electronic expansion valve,
which is a part of the refrigerant
circuit, needs to be replaced.
Only a specialized operator is
allowed to handle the refrigerant
circuit.
See document No. HRX-MM-
Q016 for replacement.
