(2) If the self-diagnostics function fails to operate
10-3. Checking the Indoor and Outdoor Units
(1) Checking the indoor unit
(2) Checking the outdoor unit
Using the TEST/T-RUN terminals
Check the indoor unit.
Is the fuse blown?
Control
No.
Check items (unit operation)
Replace the controller.
Replace the circuit
board or the fuse.
No indicators illuminate and the
indoor fan does not rotate.
Check the power voltage.
•
•
T-RUN
: Test run (compressor and fan motor turn ON).
TEST/MV : Compresses time to 1/60th (accelerates
operation by 60 times faster than normal).
Fully opens the electric expansion valve.
Press OPERATION button on the main
unit controller, or start operation
using the remote controller.
If there are no problems with the above, then check the outdoor unit.
1
Press and hold the TEST RUN button
on the main unit controller until the buzzer
sounds 1 time.
2
The rated voltage must be present between inter-unit wirings 1 and 2.
Connect a 5 kohm resistor between inter-unit cables 2 and 3. When the
voltage at both ends is measured, approximately 12 to 15 V DC must
be output and the multimeter pointer must bounce once every 8
seconds.
Or instead of measuring the voltage, you can insert an LED jig and
check that the LED flickers once every 8 seconds.
•
•
Control
No.
Check items (unit operation)
Apply the rated voltage between outdoor
unit terminals 1 and 2.
If there are no problems with the above, then check the indoor unit.
1
The control panel LED (red) must illuminate.
Short-circuit the outdoor unit COM terminal
to the T-RUN terminal.
2
The compressor and fan motor must turn ON about 5 seconds later
after the terminals are shorted.
•
•
Normal
Blown
TEST/MV T-RUN terminals
TEST/MV T-RUN
COM
Circuit
board
45
