PCB LED
Cause
Remote
controller
Indoor
unit
Outdoor
unit
– 119–
Error display
(Outdoor unit
error)
Error display
(Thermistor
error)
Error display
(Outdoor unit
error)
Outdoor thermistor faulty. Check by measuring the
thermistor resistance and
comparing it to the ambient
temperature.
Normal
display
Normal
display or
error display
(High
pressure
error)
Normal
display
Outdoor fan capacitor faulty.
Check the capacity (11uF) and
resistance of the capacitor.
(When normal, the resistance is
several hundred kilohms or
more.)
Resistance value across fan
motor wires:
Blue-white
white-red
red-blue
Outdoor fan motor faulty. Voltage (AC 30V) is applied to
motor, but motor does not rotate.
Outdoor unit electronic
expansion valve (EEV1, EEV2)
opening faulty.
Fully closed state (not open)
Cooling operation
When the heat exchange 4-way
valve (4WV2, 4WV3, 4WV4)
corresponding to the electronic
expansion valve is not energized,
the temperature (warm) of the
piping before and after the
electronic expansion valve is
clearly different.
When EEV1 and 2 are fully
closed during the cooling
operation, the high pressure may
rise abnormally and the gas may
become insufficient and both the
high pressure and low pressure
may drop.
Indoor unit
makes an
abnormal
sound.
Ball valve opening faulty.
Turn the knob of the liquid pipe,
discharge pipe, and suction pipe
clockwise.
When the ball valve is fully open,
the knob of the liquid pipe and
discharge pipe is vertical and
the knob of the suction pipe is
horizontal.
Normal
display
Normal
display or
error display
(Discharge
temperature
error)
Normal
display
Outdoor unit short circuit
Air discharged from an outdoor
unit is sucked directly into the
same outdoor unit or into another
outdoor unit.
Outdoor unit heat exchanger
block
Not enough space around
outdoor unit.
Dirt or other foreign matter stuck
to outdoor unit heat exchanger.
Refer to the design technical
manual for the service space.
Coil resistance (red-white,
red-orange, brown-blue,
brown-yellow) : 170~210
Remarks
Check method
(Error state check method)
: 20 ohms
: 40 ohms,
: 60 ohms,
Symptom that
can occur other
than title
Body
LED
Refer to the service manual
(section 8-5-1) for the
temperature and thermistor
resistance relationship.
When thermistor is shorted
or open.