6. Electrical work
Warning:
In case of A-control wiring, there is high voltage potential on the S3 terminal caused by electrical circuit design that has no electrical insulation between pow-
er line and communication signal line. Therefore, please turn off the main power supply when servicing. And do not touch the S1, S2, S3 terminals when the
power is energized. If isolator should be used between indoor unit and outdoor unit, please use 3-poles type.
WIRING SPECIFICATIONS FOR 220-240 V 50 Hz
(INDOOR-OUTDOOR CONNECTING CABLE)
Cross section of cable
Wire size (mm
Round
Flat
Flat
Round
*1 : Power supply cords of appliances shall not be lighter than design 60245 IEC or
227 IEC.
*2 : In case that cable with stripe of yellow and green is available.
*3 : In case of regular polarity connection (S1-S2-S3), wire size is 1.5 mm
*4 : In case of regular polarity connection (S1-S2-S3).
*5 : In the flat cables are connected as this picture, they can be used up to 30 m.
Be sure to connect the indoor-outdoor connecting cables directly to the units (no intermediate connections).
Intermediate connections can lead to communication errors if water enters the cables and causes insufficient insulation to ground or a poor electrical contact at the inter-
mediate connection point.
(If an intermediate connection is necessary, be sure to take measures to prevent water from entering the cables.)
7. Test run
7.1. Before test run
► After completing installation and the wiring and piping of the indoor and
outdoor units, check for refrigerant leakage, looseness in the power sup-
ply or control wiring, wrong polarity, and no disconnection of one phase
in the supply.
► Use a 500-volt megohmmeter to check that the resistance between the
power supply terminals and ground is at least 1.0 MΩ.
► Do not carry out this test on the control wiring (low voltage circuit) termi-
nals.
Warning:
Do not use the air conditioner if the insulation resistance is less than 1.0 MΩ.
Insulation resistance
After installation or after the power source to the unit has been cut for an extended
period, the insulation resistance will drop below 1 MΩ due to refrigerant accumulat-
ing in the compressor. This is not a malfunction. Perform the following procedures.
1. Remove the wires from the compressor and measure the insulation resistance
of the compressor.
2. If the insulation resistance is below 1 MΩ, the compressor is faulty or the resist-
ance dropped due the accumulation of refrigerant in the compressor.
3. After connecting the wires to the compressor, the compressor will start to warm
up after power is supplied. After supplying power for the times indicated below,
measure the insulation resistance again.
10
2
)
Number of wires
2.5
3
2.5
3
1.5
4
2.5
4
2
.
Polarity
Clockwise : S1-S2-S3
* Pay attention to stripe of yellow and green
Not applicable
(Because center wire has no cover finish)
From left to right : S1-Open-S2-S3
Clockwise : S1-S2-S3-Open
*Connect S1 and S3 to the opposite angle
*6 : Mentioned cable length is just a reference value.
It may be different depending on the condition of installation, Humidity or mate-
rials, etc.
• The insulation resistance drops due to accumulation of refrigerant in the com-
pressor. The resistance will rise above 1 MΩ after the compressor is warmed
up for four hours.
(The time necessary to warm up the compressor varies according to atmos-
pheric conditions and refrigerant accumulation.)
• To operate the compressor with refrigerant accumulated in the compressor,
the compressor must be warmed up at least 12 hours to prevent breakdown.
4. If the insulation resistance rises above 1 MΩ, the compressor is not faulty.
Caution:
• The compressor will not operate unless the power supply phase connec-
tion is correct.
• Turn on the power at least 12 hours before starting operation.
- Starting operation immediately after turning on the main power switch can result
in severe damage to internal parts. Keep the power switch turned on during the
operational season.
► The following must be checked as well.
• The outdoor unit is not faulty. LED1 and LED2 on the control board of the out-
door unit flash when the outdoor unit is faulty.
• Both the gas and liquid stop valves are completely open.
• A protective sheet covers the surface of the DIP switch panel on the control board
of the outdoor unit. Remove the protective sheet to operate the DIP switches easily.
L (m)*6
(30)
*2
Not applicable
*5
(18)
*3
(30)
*4
(3C Flat cable × 2)