Symptoms That Are Not System Malfunctions; Symptom: The System Does Not Operate; Symptom: Fan Operation Is Possible, But Cooling And Heating Do Not Work; Symptom: The Fan Speed Does Not Correspond To The Setting - Daikin RXYSCQ5TMV1B Installation And Operation Manual

Main code
Discharge temperature malfunction (outdoor)
Abnormal suction temperature (outdoor)
Refrigerant overcharge detection
High pressure switch malfunction
Low pressure switch malfunction
Fan motor trouble (outdoor)
Ambient temperature sensor malfunction (outdoor)
Pressure sensor malfunction
Current sensor malfunction
Discharge temperature sensor malfunction (outdoor)
Heat exchanger gas temperature sensor malfunction
(outdoor)
Suction temperature sensor malfunction (outdoor)
De-icing temperature sensor malfunction (outdoor)
Liquid temperature sensor (after subcool HE)
malfunction (outdoor)
Gas temperature sensor (after subcool HE)
malfunction (outdoor)
High pressure sensor malfunction (S1NPH)
Low pressure sensor malfunction (S1NPL)
INV PCB abnormal
Fin temperature abnormal
Inverter PCB faulty
Compressor over current detected
Compressor lock (startup)
Transmission outdoor unit - inverter: INV transmission
trouble
INV unbalanced power supply voltage
Fin thermistor malfunction
Capacity setting malfunction (outdoor)
Abnormal low pressure drop, faulty expansion valve
INV voltage power shortage
System test run not yet executed
Faulty wiring indoor/outdoor
Abnormal user interface - indoor communication
Faulty wiring to outdoor/outdoor
Abnormal main-sub user interface communication
System mismatch. Wrong type of indoor units
combined. Indoor unit malfunction.
Connection malfunction over indoor units or type
mismatch
Centralised address duplication
Malfunction in communication centralised control
device - indoor unit
Auto address malfunction (inconsistency)
Auto address malfunction (inconsistency)
14.2 Symptoms that are NOT system
malfunctions
The following symptoms are NOT system malfunctions:
14.2.1

Symptom: The system does not operate

▪ The air conditioner does not start immediately after the ON/OFF
button on the user interface is pressed. If the operation lamp
lights, the system is in normal condition. To prevent overloading of
the compressor motor, the air conditioner starts 5 minutes after it
RXYSCQ4~6TMV1B
VRV IV-S system air conditioner
4P555881-1 – 2019.07
Contents
is turned ON again in case it was turned OFF just before. The
same starting delay occurs after the operation mode selector
button was used.
▪ If "Under Centralized Control" is displayed on the user interface,
pressing the operation button causes the display to blink for a few
seconds. The blinking display indicates that the user interface
cannot be used.
▪ The system does not start immediately after the power supply is
turned on. Wait one minute until the micro computer is prepared
for operation.
14.2.2 Symptom: Fan operation is possible, but
cooling and heating do not work
Immediately after the power is turned on. The micro computer is
getting ready to operate and is performing a communication check
with all indoor units. Please wait 12 minutes maximally until this
process is finished.
14.2.3 Symptom: The fan speed does not
correspond to the setting
The fan speed does not change even if the fan speed adjustment
button is pressed. During heating operation, when the room
temperature reaches the set temperature, the outdoor unit goes off
and the indoor unit changes to whisper fan speed. This is to prevent
cold air blowing directly on occupants of the room. The fan speed
will not change even when another indoor unit is in heating
operation, if the button is pressed.
14.2.4 Symptom: The fan direction does not
correspond to the setting
The fan direction does not correspond with the user interface
display. The fan direction does not swing. This is because the unit is
being controlled by the micro computer.
14.2.5 Symptom: 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 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.
14.2.6 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.
14.2.7 Symptom: The user interface display
reads "U4" or "U5" and stops, but then
restarts after a few minutes
This is because the user interface is intercepting noise from electric
appliances other than the air conditioner. The noise prevents
communication between the units, causing them to stop. Operation
automatically restarts when the noise ceases.
14 Troubleshooting
Installation and operation manual
29