Samsung APH450, APH450PG0K-AFR Troubleshooting

5. Troubleshooting

	Troubleshooting
First,	Items to be checked first
Second,	Check the corrective actions in the case of occurrence of self-diagnosis mode
Third,	When the trouble is not related to the 1st or 2nd items above, check the troubled area in
	detail in accordance with the fault analysis method by symptom.

5-1 Items to be checked first

1)Is the supply voltage appropriate?

The supply voltage: should be AC 187V-AC 253V/60Hz

2)Is the connecting wire between the indoor unit and outdoor unit appropriate?

Be sure to check whether the cables for the indoor unit and outdoor unit are securely connected by the same terminal number.

3)When any claim occurs according to the contents of the table below, it is not related the trouble of the air-conditioner at all.

No.	Operation of air-conditioner	Description
1	The compressor does not operate even though	The compressor operation is delayed for 3 minutes for the protection of
	the desired temperature is set lower than	it during the restart of compressor. It operates normally after 3 minutes
	room temperature (during the cooling operation)	delay even at the initial operation.
2	The hot wind does not come out even though the	In order to prevent the discharging of cool wind, the room fan motor
	desired temperature is set higher than the room	operates only when the temperature of indoor heat exchanger is kept
	temperature. (heating operation)	higher than a constant one.
3	The wind quantity is not controlled during the	The wind quantity is set by the micom during the automatic turbo
	automatic (cooling/heating) turbo operation.	operation.
4	The temperature can not be set during the	The desired temperature is set automatically during the automatic
	automatic (cooling/heating) turbo blowing	turbo operation. The wind blowing operation is simply the operation
	operation.	mode for the circulation of indoor air.

5-2 Self-diagnosis and corrective actions

	No.	Temperature	Cause	Corrective actions
		display
1		E1	Short of indoor temperature sensor	Check of departure of indoor temperature sensor
			Open of Indoor temperature sensor	Check of PCB open/short
2		E5	Short of indoor heat exchanger sensor	Check of indoor exchanger sensor departure
			Open of indoor heat exchanger sensor	Check of PCB open/short
				Replacement of sensor
	3	E6	Short of outdoor heat exchanger sensor	Check of outdoor exchanger sensor departure
			Open of outdoor heat exchanger sensor	Check of PCB open/short
				Replacement of sensor
4		E7	Short of heater temperature sensor	Check of heater wiring diagram
			Open of heater temperature sensor	Check of sensor attachment location
5		EL	When the electrical heater is over heated	Check of heater temperature sensor departure
				Check of PCB open/shore
				Replacement of sensor

Samsung Electronics

5-1

5-3 Fault Analysis by Symptom

5-3-1 No Power (No display)

1) Checkpoints

(1)Is the voltage of the power source normal?(AC 187V - AC 253V)

(2)Is the power line in good contact?

(3)Check the power fuse(F701, F702) and PCB fuse(F101) for open.

(4)Are the primary and secondary sides of the power-trans in good contact with the connector?

(5)Is the output voltage of REG1(KA7812) normal?(DC 11.5V - DC 12.5V)

(6)Is the output voltage of REG2(KA 7805) normal?(DC 4.5V - DC 5.5V)

2) Checking procedures(after checking the checkpoints of clause 1)

Turn off the power, and then turn it on in 5 seconds.

Is the room temperature displayed on the temperaturre indicator, the display lamp turned on, and the panel

shutter down when pressing the on/off button.

N

Is the voltage or the power trans AC 18V-21V secondary side(CN11) normal?

Y

Is the output voltage of REG1 and REG2 normal? (REG1=12V, REG2=5V)

Y

Is the output wave at the MICOM(IC1) pin (No. 33~40) a square wave?

Y

Is the output wave at IC2 pin No. 11~18 a square wave?

Y

Is the harness between the main PCB and panel PCB well connected?

Y

LED display or panel PCB defective.

Y

Then it is normal operation.

N

Check and replace the power trans.

N Remove the shorted parts of the power terminal.

Replace the defective parts. (D101-104, REG1, REG2)

N

Check and replace the MICOM(IC1).

N

Check and replace the IC2.

N

Reassemble or replace the harness after checking it.

5-2	Samsung Electronics

Troubleshooting

5-3-2 When the Indoor Fan Motor does not Operate.

1) Checkpoints

(1)Is the voltage of the power source normal?(AC 187V-AC 253V)

(2)Is the indoor fan connector (CN71) in good contact?

(3)Is the starting condensor of the fan motor in good contact with the terminal?

(4)Is the resistance at both ends of the relay coil approximately 400Ω?

2)Checking procedures(after checking the checkpoints of clause 1)

Turn off the power, and then turn it on in 5 seconds.

Operate the on/off button, and operation mode key, and place it in the “FAN” position.

Does the airflow volume of the indoor fan motor change when converting into high, medium, and low by the FAN speed key?

N

Do the RY6(high), RY3(medium), and RY4(low) operate when converting into high medium and low by the FAN speed key.

N

Is the resistance at both ends/of the relay(RY 3, 4, 6) coil approximately 400Ω?

Y

Is it “high” when checking the output wave for airflow at the MICOM(IC1) pin No. 55, 56, and 53?

Y

Then the indoor fan motor is normal.

Y

Then the relay is normal.

N

Then replace the relay when resistance is 0¥ or i~.

N

Then check and replace the MICOM(IC1).

Checkthe resistance level after turning off the power.

Y

Is the voltage at both ends of the relay for each airflow at

N

Is it low when checking

N

the output wave for

the time of selecting the fan speed(high/medium/low) DC

each airflow at the IC3

Then check and replace the IC3.

12V?

pin No. 11, 12,

and 13?

Y

Y

N

Is the voltage at both ends/of indoor fan motor AC 187V~253V?

Then check the wiring harness for open.

Check and replace the indoor fan motor.

Samsung Electronics

5-3