Daikin VRV III RXYQ5-54PY1 Service Manual page 213

Symptom-based Troubleshooting
Symptom
7 The system This symptom occurs
conducts fan immediately after turning ON
operation but not the power supply.
cooling or
heating
operation.
8 The airflow rate Even pressing the AIRFLOW
is not RATE SET button makes no
reproduced changes in the airflow rate.
according to the
setting.
9 The airflow The airflow direction is not
direction is not corresponding to that
reproduced displayed on the remote
according to the controller.
setting. The flap does not swing.
10 A white mist <Indoor unit>
comes out from In cooling operation, the
the system. ambient humidity is high.
(This indoor unit is installed in
a place with much oil or dust.)
<Indoor unit>
Immediately after cooling
operation stopping, the
ambient temperature and
humidity are low.
<Indoor and outdoor units>
After the completion of
defrosting operation, the
system is switched to heating
operation.
11 The system <Indoor unit>
produces Immediately after turning ON
sounds. the power supply, indoor unit
produces "ringing" sounds.
<Indoor and outdoor units>
"Hissing" sounds are
continuously produced while in
cooling or defrosting operation.
<Indoor and outdoor units>
"Hissing" sounds are produced
immediately after the startup or
stop of the system, or the
startup or stop of defrosting
operation.
<Indoor unit>
Faint sounds are continuously
produced while in cooling
operation or after stopping the
operation.
<Indoor unit>
"Creaking" sounds are
produced while in heating
operation or after stopping the
operation.
<Indoor unit>
Sounds like "trickling" or the
like are produced from indoor
units in the stopped state.
<Outdoor unit>
Pitch of operating sounds
changes.
202
Supposed Cause
The system is in preparation
mode of operation.
In heating operation, when the
room temperature reaches the set
degree, the outdoor unit will stop
while the indoor unit is brought to
fan LL operation so that no one
gets cold air.
Furthermore, if fan operation
mode is selected when other
indoor unit is in heating operation,
the system will be brought to fan
LL operation.
(The fan LL operation is also
enabled while in oil return mode in
cooling operation.)
Automatic control
Uneven temperature distribution
due to heavy stain of the inside of
the indoor unit
Hot gas (refrigerant) flown in the
indoor unit results to be vapor
from the unit.
Defrosted moisture turns to be
vapor and comes out from the
units.
These are operating sounds of
the electronic expansion valve of
the indoor unit.
These sounds are produced from
gas (refrigerant) flowing
respectively through the indoor
and outdoor units.
These sounds are produced
when the gas (refrigerant) stops
or changes flowing.
These sounds are produced from
the drain discharge device in
operation.
These sounds are produced from
resin parts expanding and
contracting with temperature
changes.
On VRV systems, these sounds
are produced when other indoor
units in operation. The reason is
that the system runs in order to
prevent oil or refrigerant from
dwelling.
The reason is that the compressor
changes the operating frequency.
Si34-601A
Countermeasure
Wait for a period of approximately
10 minutes.
Normal operation.
Normal operation.
Clean the inside of the indoor unit.
Normal operation.
Normal operation.
Normal operation.
This sound becomes low after a
lapse of approximately one
minute.
Normal operation.
Normal operation.
Normal operation.
Normal operation.
Normal operation.
Normal operation.
Troubleshooting