On (Max. 90 M); Symptom-Based Troubleshooting - Daikin RXQ12AHR Service Manual

Symptom-based Troubleshooting

2. Symptom-based Troubleshooting
Symptom
1 The system does not start operation at all.
2 The system starts operation but makes an
immediate stop.
3 The system does not cool or heat air well.
4 The system does The system stops and
not operate. immediately restarts
operation.
Pressing the temperature
setting 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 stops immediately
after turning ON the power
supply.
5 The system The remote controller displays
makes error codes U4 or U5, and the
intermittent system stops but restarts after
stops. a lapse of several minutes.
6 The system This symptom occurs
conducts fan immediately after turning ON
operation but not the power supply.
cooling
The remote controller displays
operation.
UNDER CENTRALIZED
CONTROL; no cooling
operation is performed. Switch
to fan operation.
162
Supposed Cause
Blowout of fuse(s)
Cutout of breaker(s)
Power failure
The connector loose or not fully
plugged in
Blocked air inlet or outlet of indoor
or outdoor unit
Clogged air filter(s)
Blocked air inlet or outlet of indoor
or outdoor unit
Clogged air filter(s)
Enclosed outdoor unit(s)
Improper set temperature
Airflow rate set to LOW
Improper direction of air diffusion
Open window(s) or door(s)
IN COOLING
Direct sunlight received
IN COOLING
Too many people staying in a room
IN COOLING
Too many heat sources (e.g. OA
equipment) located in a room
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.
The system is controlled with
centralized controller. Blinking
display indicates that the system
cannot be operated using the
remote controller.
The system is in preparation mode
of microcomputer operation.
The system stops due to an
interruption in communication
between units caused by electrical
noises coming from equipment
other than air conditioners.
The system is in preparation mode
of operation.
In thermal storage operation, the
unit is set to fan operation in cooling
operation, and the remote controller
shows CENTRALIZED CONTROL.
SiAF341904E
Countermeasure
Turn Off the power supply and then
replace the fuse(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.
ON
Knob
Tripped
OFF
Circuit breaker
After the power failure is reset,
restart the system.
Turn off the power supply to verify
the connection of the connector.
Remove obstacle(s).
Clean the air filter(s).
Remove obstacle(s).
Clean the air filter(s).
Remove the enclosure.
Set the temperature to a proper
degree.
Set it to a proper airflow rate.
Set it to a proper direction.
Shut it tightly.
Hang curtains or shades on
windows.
The model must be selected to
match the air conditioning load.
Normal operation. The system will
automatically start operation after a
lapse of five minutes.
Operate the system using the
COOL/HEAT centralized remote
controller.
Wait for a period of approximately
one minute.
Remove causes of electrical noises.
If these causes are removed, the
system will automatically restart
operation.
Wait for a period of approximately
10 minutes.
Normal operation.
Part 6 Service Diagnosis