Daikin REYQ72-456XATJU, Service Manual

Page: 243 / 441

SiUS371901E Symptom-based Troubleshooting
Service Diagnosis 230
Symptom Supposed Cause Countermeasure
11 The system
produces
sounds.
Indoor unit
Immediately after turning ON
the power supply, indoor unit
produces ringing sounds.
These are operating sounds of the
electronic expansion valve of the
indoor unit. Normal operation.
This sound becomes low after a
lapse of approximately one minute.
Indoor and outdoor units
Hissing sounds are
continuously produced while in
cooling or defrost control.
These sounds are produced from
gas (refrigerant) flowing
respectively through the indoor and
outdoor units. Normal operation.
Indoor and outdoor units
Hissing sounds are produced
immediately after the startup or
stop of the system, or the
startup or stop of defrost
control.
These sounds are produced when
the gas (refrigerant) stops or
changes flowing. Normal operation.
Indoor unit
Faint sounds are continuously
produced while in cooling
operation or after stopping the
operation.
These sounds are produced from
the drain discharge device in
operation. Normal operation.
Indoor unit
Creaking sounds are produced
while in heating operation or
after stopping the operation.
These sounds are produced from
resin parts expanding and
contracting with temperature
changes. Normal operation.
Indoor unit
Sounds like trickling or the like
are produced from indoor units
in the stopped state.
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.
Normal operation.
Outdoor unit
Pitch of operating sounds
changes.
The reason is that the compressor
changes the operating frequency. Normal operation.
12 Dust comes out
from the system.
Dust comes out from the
system when it restarts after
the stop for an extended period
of time. Dust, which has deposited on the
inside of indoor unit, is blown out
from the system. Normal operation.
13 Odors come out
from the system.
In operation Odors of room, cigarettes or else
adsorbed to the inside of indoor unit
are blown out. The inside of the indoor unit should
be cleaned.
14 Outdoor fan
does not rotate.
In operation The reason is that fan revolutions
are controlled to put the operation to
the optimum state. Normal operation.
15 LCD display 88
appears on the
remote
controller.
Immediately after turning ON
the power supply The reason is that the system is
checking to be sure the remote
controller is normal. Normal operation.
This code is displayed for a period
of approximately one minute at
maximum.
16 The outdoor unit
compressor or
the outdoor fan
does not stop.
After stopping operation It stops in order to prevent oil or
refrigerant from dwelling. Normal operation.
It stops after a lapse of
approximately 5 to 10 minutes.
17 The outdoor gets
hot.
While stopping operation The reason is that the compressor
is warmed up to provide smooth
startup of the system. Normal operation.
18 Hot air comes
out from the
system even
though it stops.
Hot air is felt while the system
stops. On VRV systems, small quantity of
refrigerant is fed to indoor units in
the stopped state when other indoor
units are in operation.
Normal operation.
19 The system does
not cool air well.
The system is in dry operation. The reason is that the dry operation
serves not to reduce the room
temperature where possible.
Change the system to cooling
operation.