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23. SELF DIAGNOSTIC FUNCTION FOR MALFUNCTIONS DETECTION
EXPLAINATION OF SELF-DIAGNOSTIC FUNCTION
- Self-diagnostic function is the key for success of air conditioner operation.
- The printed circuit boards existing inside the indoor unit are equipped with self-diagnostic function
to detect malfunction and automatically stops the operation at the air conditioner.
- Once a malfunction is detected, the diagnostic control section will force the system mode to OFF
for 3 minutes. After the OFF delay, system mode releases and allowed returning to its normal state.
The system will be allowed to restart on its own.
The diagnostic control section will allow the system to fail 5 consecutive times before shutting
down the system.
If the system is performing an active defrost, both the compressor drive and reversing valve
malfunction test will be cancelled and reinitiated after the following compressor OFF-ON cycle.
-
The unit on lamp is scanned every half-second and the error codes are displayed by the flashing
frequency of unit on lamp. The error codes are displayed during SHUT-OFF (3 minutes off and after
the 5
th
retry failure).
Green led flashes if there is a malfunction of the system.
Flashing frequency of green led refers to malfunction type.
Sr.
Malfunction
Reason
Flashing
Frequency
Allowed
Modes
1
Return Air Sensor
( open circuit or short circuit )
2
Fan Only
2
Indoor Coil Sensor
( open circuit or short circuit )
3
Fan Only
3
Compressor Drive Malfunction
5
Fan Only
4
Reversing Valve Malfunction
( only for Heat Pump System )
6
Fan Only
5
Power Line Feedback
(zero crossing)
9
-
NOTES
1-
If more than two malfunctions occur, the highest malfunction as per the serial in the above table
is displayed.
If the highest malfunction is cleared, the next malfunction is displayed.
2-
Prior to the malfunction repair, disconnect the electrical mains supply by moving the circuit
breaker to OFF position.
3-
After repairing the malfunction:
3-1 connect the electrical main supply by moving the circuit breaker to ON position
3-2 operate the air conditioner by using the wireless remote control.
Indoor Unit
Summary of Contents for 38QPCT18C-708
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