Daikin REYQ8-48PY1B, Service Manual

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Symptom-based Troubleshooting SiBE37-701_B
239 Troubleshooting
1. Symptom-based Troubleshooting
Symptom Supposed Cause Countermeasure
1 The system does not start operation at all. Blowout of fuse(s) Turn Off the power supply and
then replace the fuse(s).
Cutout of breaker(s) • If the knob of any breaker is in
its OFF position, turn ON the
power supply.
• If the knob of any circuit
breaker is in its tripped position,
do not turn ON the power
supply.
Power failure After the power failure is reset,
restart the system.
2 The system starts operation but makes an
immediate stop. Blocked air inlet or outlet of indoor
or outdoor unit Remove obstacle(s).
Clogged air filter(s) Clean the air filter(s).
3 The system does not cool or heat air well. Blocked air inlet or outlet of indoor
or outdoor unit Remove obstacle(s).
Clogged air filter(s) Clean the air filter(s).
Enclosed outdoor unit(s) Remove the enclosure.
Improper set temperature Set the temperature to a proper
degree.
Airflow rate set to "LOW" Set it to a proper airflow rate.
Improper direction of air diffusion Set it to a proper direction.
Open window(s) or door(s) Shut it tightly.
[In cooling] Direct sunlight received Hang curtains or shades on
windows.
[In cooling] Too many persons staying in a
room
The model must be selected to
match the air conditioning load.
[In cooling] Too many heat sources (e.g. OA
equipment) located in a room
4 The system does
not operate. The system stops and
immediately restarts operation. If the OPERATION lamp on the
remote controller turns ON, the
system will be normal. These
symptoms indicate that the
system is controlled so as not to
put unreasonable loads on the
system. Normal operation. The system will
automatically start operation after
a lapse of five minutes.
Pressing the TEMP ADJUST
button immediately resets the
system.
The remote controller displays
"UNDER CENTRALIZED
CONTROL", which blinks for a
period of several seconds
when the OPERATION button
is depressed. The system is controlled with
centralized controller. Blinking
display indicates that the system
cannot be operated using the
remote controller. Operate the system using the
COOL/HEAT centralized remote
controller.
The system stops immediately
after turning ON the power
supply. The system is in preparation
mode of micro-computer
operation. Wait for a period of approximately
one minute.
5 The system
makes
intermittent
stops. The remote controller displays
malfunction codes "U4" and
"U5", and the system stops but
restarts after a lapse of several
minutes. The system stops due to an
interruption in communication
between units caused by
electrical noises coming from
equipment other than air
conditioners. Remove causes of electrical
noises.
If these causes are removed, the
system will automatically restart
operation.
6 COOL-HEAT
selection is
disabled. The remote controller displays
"UNDER CENTRALIZED
CONTROL". This remote controller has no
option to select cooling operation. Use a remote controller with
option to select cooling operation.
The remote controller displays
"UNDER CENTRALIZED
CONTROL", and the COOL-
HEAT selection remote
controller is provided. COOL-HEAT selection is made
using the COOL-HEAT selection
remote controller. Use the COOL-HEAT selection
remote controller to select cool or
heat.
ON
Knob
Tripped
OFF
Circuit breaker