Daikin UAL-A Series - Page 47

46
13
The LED indicator
of the unit displays
ER27 and the wired
controller displays 27
Ambient temperature is too
high/low
The ambient temperature sensor has
broken down
Replace the ambient temperature
sensor
The ambient temperature is too high/
low
OFF
14
The LED indicator
of the unit displays
ER29 and the wired
controller displays 29
Superheat of #1 is too low
The low pressure sensor or
temperature sensor has broken down
Replace
The electronic expansion valve fails to
provide proper control
Upgrade the modular program
15
The LED indicator
of the unit displays
ER31
Communication failure between
the master unit and slave units
Communication line of the slave unit
has broken off
Check and troubleshoot the
communication lines.
Incorrect DIP address setting for the
slave unit
Reset the addresses of all slave
units and check that there is no
duplicate address
The number of slave unit is set
incorrectly for the master unit
Reset the number of slave units
and check that the number match
with all the addresses
The PC communication port of the
slave unit has broken down
1. Exchange positions of the two
485 on the slave unit
2. Replace the control panel of
the unit"
The PC communication port of the
slave unit has broken down
Connect the communication line
of the slave unit to the Apc/Bpc
port
16
The LED indicator
of the unit displays
ER32 and the wired
controller displays 32
Temperature of return air in #1
is too high (40°C)
The slider of the 4-way valve is
jammed in the middle
Restart the unit and slap slightly
on both sides of the 4-way valve.
If the problem persists, replace
the 4-way valve.
The winding of the 4-way valve
operates abnormally
Replace the winding
The temperature of discharge air is
too high and has triggered the racing
protector of the compressor
(see Item 17 in the table)
17
The LED indicator
of the unit displays
ER33 and the wired
controller displays 33
Temperature of discharge air in
#1 is too high
The fan motor has broken down
(cooling)
Check and troubleshoot the unitCirculatory air is shorted (cooling)
The heat exchanger needs cleaning
(cooling)
The electronic expansion valve is not
opened as expected (heating)
Check and troubleshoot the
electronic expansion valve
The water temperature is too high
Change the setting for return
water temperature (to be
performed by service personnel)
Insufcient refrigerant or leakage
Replenish a proper amount of
refrigerant
Incomplete defrosting
Change the defrosting parameter
(to be performed by service
personnel)
18
The LED indicator
of the unit displays
ER34 and the wired
controller displays 34
Temperature of return air in #2
is too high (40°C)
The slider of the 4-way valve is
jammed in the middle
Restart the unit and slap slightly
on both sides of the 4-way valve.
If the problem persists, replace
the 4-way valve.
The winding of the 4-way valve
operates abnormally
Replace the winding
The temperature of discharge air is
too high and has triggered the racing
protector of the compressor
(see Item 19 in the table)