Problem Symptoms and Measures
Si12-714
172
Service Diagnosis
2.
Problem Symptoms and Measures
Problem Symptom
Check Item
Details of Measure
Page
No.
to be
referred
None of the units operates. Check the power supply.
Check to make sure that the rated voltage is
supplied.
—
Check the type of the indoor units.
Check to make sure that the indoor unit type is
compatible with the outdoor unit.
—
Check the outdoor air temperature.
Heating operation cannot be used when the
outdoor air temperature is 21°C or higher (only
for heat pump model), and cooling operation
cannot be used when the outdoor air
temperature is below –10 °C (heat pump
model), 10°C (cooling only model).
—
Diagnosis with indoor unit LED
indication
—
Diagnosis with outdoor unit LED
indication
—
Check the remote controller
addresses.
Check to make sure that address settings for
the remote controller and indoor unit are
correct.
—
Operation sometimes
stops.
Check the power supply.
A power failure of 2 to 10 cycles can stop air
conditioner operation. (Operation lamp OFF)
—
Check the outdoor air temperature.
Heating operation cannot be used when the
outdoor air temperature is 21°C or higher (only
for heat pump model), and cooling operation
cannot be used when the outdoor air
temperature is below –10°C (heat pump
model), 10°C (cooling only model).
—
Diagnosis with indoor unit LED
indication
—
Diagnosis with outdoor unit LED
indication
—
Some indoor units do not
operate.
Check the type of the indoor units.
Check to make sure that the indoor unit type is
compatible with the outdoor unit.
—
Diagnosis with indoor unit LED
indication
—
Diagnosis with outdoor unit LED
indication
—
Equipment operates but
does not cool, or does not
heat (only for heat pump
model).
Check for wiring and piping errors in
the indoor and outdoor units
connection wires and pipes.
Conduct the wiring/piping error check described
on the product diagnosis nameplate.
—
Check for thermistor detection errors. Check to make sure that the main unit’s
thermistor has not dismounted from the pipe
holder.
—
Check for faulty operation of the
electronic expansion valve.
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.
—
Diagnosis with indoor unit LED
indication
—
Diagnosis with outdoor unit LED
indication
—
Diagnosis by service port pressure
and operating current
Check for insufficient gas.
Large operating noise and
vibrations
Check the output voltage of the
power transistor.
—
Check the power transistor.
—
—
Check the installation condition.
Check to make sure that the required spaces
for installation (specified in the Engineering
Data book, etc.) are provided.
—
