Problem Symptoms And Measures - Daikin Super Multi NX FFQ25B8V1B Service Manual

SiBE121021_C

2. Problem Symptoms and Measures

Problem Symptom
None of the units operates. Check the power supply.
Operation sometimes
stops.
Some indoor units do not
operate.
Units operate but do not
cool, or do not heat.
Large operating noise and
vibrations
Service Diagnosis
Check Item
Check the type of the indoor units.
Check the outdoor temperature.
Diagnose with remote controller
indication
Check the remote controller
addresses.
Check the power supply.
Check the outdoor temperature.
Diagnose with remote controller
indication.
Check the type of the indoor units.
Diagnose with remote controller
indication
Check for wiring and piping errors in
the connection between the indoor
and outdoor units.
Check for thermistor detection errors. Check if the thermistor is mounted securely.
Check for faulty operation of the
electronic expansion valve.
Diagnose with remote controller
indication.
Diagnose by service port pressure
and operating current.
Check the output voltage of the
power module.
Check the power module.
Check the installation condition.

Problem Symptoms and Measures

Details of Measure
Check if the rated voltage is supplied.
Check if the indoor unit type is compatible with
the outdoor unit.
Heating operation cannot be used when the
outdoor temperature is 20°C or higher, and
cooling operation cannot be used when the
outdoor temperature is below –10 ~ 10°C
(depending on the model).
—
Check if address settings for the remote
controller and indoor unit are correct.
A power failure of 2 to 10 cycles can stop air
conditioner operation. (Operation lamp OFF)
Heating operation cannot be used when the
outdoor temperature is 20°C or higher, and
cooling operation cannot be used when the
outdoor temperature is below –10 ~ 10°C
(depending on the model).
—
Check if the indoor unit type is compatible with
the outdoor unit.
—
Conduct the wiring/piping error check described
on the product diagnosis nameplate.
Set all the units to cooling operation, and
compare the temperatures of the liquid pipes to
see if the each electronic expansion valve
works.
—
Check for refrigerant shortage.
—
—
Check if the required spaces for installation
(specified in the installation manual, etc.) are
provided.
Reference
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