Daikin REYQ-AATJA, Service Manual

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Symptom-based Troubleshooting SiUS372201EA
267 Part 6 Service Diagnosis
1. Symptom-based Troubleshooting
1.1 Indoor Unit Overall
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.
The connector loose or not fully
plugged in
Turn off the power supply to verify the
connection of the connector.
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
IN DRYING
The reason is that the dry operation
serves not to reduce the room
temperature where possible.
Change the system to cooling
operation.
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 temperature
setting button immediately
resets the system.
The remote controller displays
CENTRAL 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 central remote
controller.
The system stops immediately
after turning ON the power
supply.
The system is in preparation mode of
microcomputer operation.
Wait for a period of approximately
one minute.
5 The system
makes
intermittent stops.
The remote controller displays
error codes U4 or 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.
O N
Kno b
Tripped
OFF
Circ u it b reaker