Problem And Solution - Daikin FT25CV1A Service Manual

Si01-406
2.

Problem and Solution

Problem
None of the units operates. Check the power supply.
Operation sometimes
stops.
Equipment operates but
does not cool, or does not
heat (only for heat pump
model).
Large operating noise and
vibrations
Service Diagnosis
Check
Check the type of the indoor units.
Check the outdoor air temperature.
Diagnosis with remote controller
indication
Check the remote controller
addresses.
Check the power supply.
Check the outdoor air temperature.
Diagnosis with remote controller
indication
Check for wiring and piping errors in
the indoor and outdoor units
connection wires and pipes.
Check for thermistor detection errors. Check to make sure that the main unit's
Check for faulty operation of the
electronic expansion valve.
Diagnosis with remote controller
indication
Diagnosis by service port pressure
and operating current
Check the output voltage of the
power transistor.
Check the power transistor.
Check the installation condition.
Solution
Check to make sure that the rated voltage is
supplied.
Check to make sure that the indoor unit type is
compatible with the outdoor unit.
Heating operation cannot be used when the
outdoor air temperature is 21°C or higher, and
cooling operation cannot be used when the
outdoor air temperature is below 10°C (19.4°C
for cooling only model).
—
Check to make sure that 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 air temperature is 21°C or higher, and
cooling operation cannot be used when the
outdoor air temperature is below 10°C (19.4°C
for cooling only model).
—
Conduct the wiring/piping error check described
on the product diagnosis nameplate.
thermistor has not dismounted from the pipe
holder.
Set the units to cooling operation, and compare
the temperatures of the liquid side connection
pipes of the connection section among rooms to
check the opening and closing operation of the
electronic expansion valves of the individual
units.
—
Check for insufficient gas.
—
—
Check to make sure that the required spaces
for installation (specified in the Technical
Guide, etc.) are provided.

Problem and Solution

Reference
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