Acson international A5MAC 210D, Technical Manual

Page: 44 / 49

46
S/N Failure Code Symptom Possible Cause Solution
11
The LED indicator
of the unit displays
ER25 and the
wired controller
displays 25
Anti-freezing
protection failed
1. Return water temperature is set
too low.
Modify the set temperature of the return
water.
2. Insufficient water flow rate causing
temperature difference too high.
Check the water system (refer to item 7).
12
The LED indicator
of the unit displays
ER26 and the
wired controller
displays 26
Electric heater for
water system is
overloaded
1. Check whether the unit is supplied with
an electric heater.
If the unit is confirmed without heater,
bypass the switch
2. Electric heater wire is short-circuited. Check and replace if needed.
13
The LED indicator
of the unit displays
ER27 and the
wired controller
displays 27
Ambient temperature
is too high or low
1. Ambient temperature sensor faulty Check and replace if needed.
2. Ambient temperature is too high/low Shut down the unit.
14
The LED indicator
of the unit displays
ER29 and the
wired controller
displays 29
System 1 suction
superheat is too low
1. Low pressure or temperature sensor
is faulty
Check and replace if needed.
2. Electronic expansion valve control
algorithm malfunctioned.
Update the module
15
The LED indicator
of the unit displays
ER31 and the
wired controller
displays 31
Communication
failure between
master and slave
units
1. Communication line of the slave unit
has loosen.
Check the communication cables and
troubleshoot accordingly.
2. Incorrect DIP address setting for the
slave unit.
Reset the addresses of all slave units and
ensure that there is no duplicate address.
3. The number of slave unit is set for the
master unit is incorrect.
Reset the number of slave units and check
that the number match with all the addresses.
.
4. Slave unit PC communication port is
damaged
1. Exchange positions of the two 485
interfaces on the control panel of the slave
unit.
2. Replace the control panel of the unit.
5. Communication line of the slave unit
connected to wrong port.
Connect communication cables of the slave
unit to Apc/Bpc port.
16
The LED indicator
of the unit displays
ER32 and the
wired controller
displays 32
System 1 suction
temperature is too
high (40°C)
1. Four-way valve jammed.
Gently knock the sides of the four-way valve
and restart the system. Should the alarm
persist, replace the four-way valve.
2. Incorrect coil operation of the four-way
valve.
Replace the coil.
3. Compressor idle protection due to air
discharge temperature is too high.
Refer to item 17 in the table.
17
The LED indicator
of the unit displays
ER33 and the
wired controller
displays 33
System 1 discharge
temperature is too
high
1. Damaged fan motor (cooling).
Check and troubleshoot accordingly.
Recover and recharge accordingly.
2. Air circulation short circuited (cooling)
.
3. Heat exchanger is dirty (cooling).
4. The electronic expansion valve is not
opened as expected (heating).
Check the electronic expansion valve and
troubleshoot accordingly.
5. Water temperature is too high.
Insufficient refrigerant or leakages.
Change the setting for return water
temperature to be performed by service
personnel.
6.
7. Incomplete defrosting.
Change the defrosting parameter to be
performed by service personnel