Daikin VRV II Series, Design, Installation & Testing Instructions, Page: 222 / 242

Following Symptoms are not Air Conditioner Troubles Si39-303
216 Operation Manual
8.6 White Mist comes out of a Unit
Indoor unit
!
When humidity is high during cooling operation.
If the interior of an indoor unit is extremely contaminated, the temperature distribution inside
a room becomes uneven. It is necessary to clean the interior of the indoor unit. Ask your
Daikin dealer for details on cleaning the unit. This operation requires a qualified service
person.
!
Immediately after the cooling operation stops and if the room temperature and
humidity are low.
This is because warm refrigerant gas flows back into the indoor unit and generates steam.
Indoor unit, outdoor unit
!
When the system is changed over to heating operation after defrost operation.
Moisture generated by defrost becomes steam and is exhausted.
8.7 Noise of Air Conditioners
Indoor unit
!
A “zeen” sound is heard immediately after the power supply is turned on.
The electronic expansion valve inside an indoor unit starts working and makes the noise. Its
volume will reduce in about one minute.
!
A continuous low “shah” sound is heard when the system is in cooling operation or
at a stop.
When the drain pump (optional accessories) is in operation, this noise is heard.
!
A “pishi-pishi” squeaking sound is heard when the system stops after heating
operation.
Expansion and contraction of plastic parts caused by temperature change make this noise.
!
A low “sah”, “choro-choro” sound is heard while the indoor unit is stopped.
When the other indoor unit is in operation, this noise is heard. In order to prevent oil and
refrigerant from remaining in the system, a small amount of refrigerant is kept flowing.
Indoor unit, outdoor unit
!
A continuous low hissing sound is heard when the system is in cooling or defrost
operation.
This is the sound of refrigerant gas flowing through both indoor and outdoor units.
!
A hissing sound which is heard at the start or immediately after stopping operation or
defrost operation.
This is the noise of refrigerant caused by flow stop or flow change.
8.8 Dust comes out of the Unit
!
When the unit is used for the first time in a long time.
This is because dust has gotten into the unit.
Outdoor unit
!
When the tone of operating noise changes.
This noise is caused by the change of frequency.
8.9 The Units can Give off Odours
!
The unit can absorb the smell of rooms, furniture, cigarettes, etc., and then emit it
again.
8.10 The Outdoor Unit Fan does not Spin
!
During operation.
The speed of the fan is controlled in order to optimize product operation.