FILE NO. SVM-10019
Block distinction Operation of diagnosis function
Check
code
Block
Check
code
Cause of operation
Air
conditioner
status
Display flashing
error
Serial signal 1) Defective wiring of the Indoor unit Flashes when 1) to 3) The outdoor unit never
and connecting connecting cable or operates error is detected. operate.
cable. miss-wiring. continue. Flashing stop Check connecting cable and correct
2) Operation signal has not Outdoor unit and outdoor unit if defective wiring.
send from the indoor unit stop. start to operate Check 25A fuse of inverter P.C. board.
when operation start. when the return Check 3.15A fuse of inverter
3) Outdoor unit has not signal from the P.C. board.
send return signal to the outdoor unit is Check operation signal of the indoor
indoor unit when operation normal. unit by using diode. Measure voltage
started. at terminal block of the indoor unit
4) Return signal from the between No.2 and No.3 (or L2 and S)
outdoor unit is stop during If signal is varied 15-60V continuously,
operation. replace inverter P.C. board.
Some protector If signal is not varied, replace indoor
(hardware, if exist) of the P.C. board.
outdoor unit open 4) The outdoor unit abnormal stop at
circuit of signal. some time.
Signal circuit of indoor If the other check codes are found
P.C. board or outdoor concurrently, check them together.
P.C. board is failure Check protector (hardware) such
in some period. as Hi-Pressure switch,
Thermal-Relay, etc.
Check refrigerant amount or any
possibility case which may caused
high temperature or high pressure.
Check operation signal of the indoor
unit by using diode. Measure voltage
at terminal block of the indoor unit
between No.2 and No.3 (or L2 and S)
If signal is varied 15-60V continuously,
replace inverter P.C. board.
If signal is not varied, replace indoor
P.C. board.
Action and Judgment
* Signal send only 1 minute and stop. Because of return signal from outdoor unit has not received.
** Signal resend again after 3 minutes stop. And the signal will send continuously.
*** 1 minute after resending, the indoor unit display flashes error.
VDC
Time (Min)
0
34 78
15
60
Measured signal voltage by apply diode
3 minutes Delay, start
counting from power
supply ON or remote
OFF.
3 minutes stop
*
**
***
Sending signal of the indoor unit when have not return
signal from the outdoor unit.
Voltage variation stop
or have not voltage
output.
Note : Operation signal of the indoor unit shall be measured in the sending period as
picture below.
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