Daikin FXKA25AMVEB User Reference Manual

Also see for FXKA20AMVEB: Installation and operation manual

11 | TroubleshootingInstaller and user reference guide40FXKA-AVRV system air conditioner4P747548-2 – 2023.1111.1.4 Symptom: White mist comes out of a unit (Indoor unit)▪ When humidity is high during cooling operation. If the interior of an indoor unit isextremely contaminated, the temperature distribution inside a room becomesuneven. It is necessary to clean the interior of the indoor unit. Ask your dealer fordetails on cleaning the unit. This operation requires a qualified service person.▪ Immediately after the cooling operation stops and if the room temperature andhumidity are low. This is because warm refrigerant gas flows back into the indoorunit and generates steam.11.1.5 Symptom: White mist comes out of a unit (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.11.1.6 Symptom: The user interface reads "U4" or "U5" and stops, but then restarts after a fewminutesThis is because the user interface is intercepting noise from electric appliancesother than the air conditioner. The noise prevents communication between theunits, causing them to stop. Operation automatically restarts when the noiseceases. A power reset may help to remove this error.11.1.7 Symptom: Noise of air conditioners (Indoor unit)▪ A "zeen" sound is heard immediately after the power supply is turned on. Theelectronic expansion valve inside an indoor unit starts working and makes thenoise. Its volume will reduce in about one minute.▪ A continuous low "shah" sound is heard when the system is in cooling operationor at a stop. When the drain pump is in operation, this noise is heard.▪ A "pishi-pishi" squeaking sound is heard when the system stops after heatingoperation. Expansion and contraction of plastic parts caused by temperaturechange make this noise.11.1.8 Symptom: Noise of air conditioners (Indoor unit, outdoor unit)▪ A continuous low hissing sound is heard when the system is in cooling or defrostoperation. This is the sound of refrigerant gas flowing through both indoor andoutdoor units.▪ A hissing sound which is heard at the start or immediately after stoppingoperation or defrost operation. This is the noise of refrigerant caused by flowstop or flow change.11.1.9 Symptom: Dust comes out of the unitWhen the unit is used for the first time in a long time. This is because dust hasgotten into the unit.11.1.10 Symptom: The units can give off odoursThe unit can absorb the smell of rooms, furniture, cigarettes, etc., and then emit itagain.