30
Check of LEV (Expansion valve)
Check of current-limiting resistor
K
Outdoor unit does not operate at all or stops immediately due to over current.
Replace the power P.C. board.
When the current-limiting resistor is open, the rush current limiting relay (X64) may not work properly.
Does current-limiting resistor (R64) detect 10
"
?
No
∞
Yes
Ok
Start
L
Heating/Cooling does not work sufficiently.
Replace the LEV.
With remote controller set toward the indoor unit, press
the OPERATE/ STOP(ON/ OFF) button and confirm one
beep tone.
LEV operates in full-opening
direction.
Is LEV properly fixed to the
expansion valve?
Ok
Do you hear the expansion
valve "click, click·······"?
Do you feel the expansion
valve vibrate on touching it ?
Does the resistance of LEV
have the characteristics on
page 25?
Measure each voltage between connector pins
of CN724 on the inverter P.C. board.
1.Pin
3
(-) Pin
1
(+)
2.Pin
4
(-) Pin
1
(+)
3.Pin
5
(-) Pin
1
(+)
4.Pin
6
(-) Pin
1
(+)
Is there about 3~5V AC between each?
NOTE: Measure the voltage by an analog tester.
No
Yes
Yes
Yes
No
Replace the
expansion valve.
Yes
No
No
Properly fix the LEV to the
expansion valve.
Replace the
inverter P.C. board.
NOTE : After check of LEV, do the undermentioned
operations.
1. Turn OFF the power supply and
turn ON again.
2. Press the RESET button on the remote
controller.
Turn ON the power supply.
1
During pressing both the OPERATION SELECT
button and the TOO COOL button on the
remote controller at the same time,
press the RESET button.
2
First, release the RESET button.
And release the other two buttons since all LCD
in operation display section of the remote controller
is displayed after 3 seconds.
1
During pressing both the OPERATION SELECT
button and the TOO COOL button on the
remote controller at the same time,
press the RESET button.
2
First, release the RESET button.
And release the other two buttons since all LCD
in operation display section of the remote controller
is displayed after 3 seconds.
AMPM
CLOCK
:
AMPM
Check of defrost heater
M
Replace the inverter P.C. board.
Is there 230V AC between CN722
1
and
3
on the
power P.C. board?
Yes
No
No problem of the
power P.C. board.
Is the voltage between CN726
6
(+)-
3
(-)
on the
power P.C. board 0V DC? (Refer to page 33.)
Yes
No
Replace the power
P.C. board.
NOTE: In case both thermistors are more than the above
temperature, cool them with cold water etc...
In HEAT mode, for more than 5 minutes, let the ambient temperature thermistor continue to read 5
:
or less, and let the
defrost thermistor continue to read -1
:
or less.
3
2
1
230V AC
Check the following points before checking electric continuity.
1) Does the resistance of ambient temperature thermistor have the characteristics? (Refer to page 32.)
2) Is the resistance of defrost heater normal? (Refer to page 25.)
3) Does the heater protector remain conducted (not open)?
4) Are both ambient temperature thermistor and circuit of defrost heater securely connected to connectors?
26H
CN726
CN722
H
2
1
2
1
3
6
Outdoor base gets frozen.
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OB328 A--1qxp 04.4.26 4:49 PM Page 30
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