Panasonic Cs A9ekh Cu A9ekh Cs A12ekh Cu A12ekh Repair Manual

							31 • Automatic Set Temperature
For each operation, set temperature will automatically set as shown below.
However it can be selected 2°C higher or 2°C lower from standard set temperature by pressing the “Room Temperature Setting
button”.
• The setting temperature for all the operations can be changed one level up or one level down from the standard temperature as
shown in below table by pressing on the temperature up or temperature down button at remote control.
• The operation mode judging temperature and standard setting temperature can be increased by 2°C permanently, by open the
circuit of JX1 at indoor electronic controller.
11.5. Operation Control
11.5.1. Restart Control (Time Delay Safety Control)
•When the thermo-off temperature (temperature which compressor stops to operate) is reached during:-
- Cooling/Heating operation - the compressor stops for 3 minutes (minimum) before resume operation.
- Soft Dry operation - the compressor stops for 6 minutes (minimum) before resume operation.
• If the operation is stopped by the remote control, the compressor will not turn on within 3 minutes from the moment operation
stop, although the unit is turn on again within the period.
•This phenomenon is to balance the pressure inside the refrigerant cycle.
11.5.2. Compressor Reverse Rotation Protection Control
• If the compressor is operating continuously for 5 minutes or longer and the temperature difference between intake air and indoor
heat exchanger is 2.5°C (cooling mode)/5°C (heating mode) or less for continuous 2 minutes, compressor will stop and restart
automatically.
• Time Delay Safety Control is activated before the compressor restart.
s T = Intake air temperature - Indoor heat exchanger temperature
• This is to prevent compressor from rotate reversely when there is an instantaneous power failure.
Operation Hi (Standard) Lo
(+2°C) (±0°C) (-2°C)
Coolig 27°C25°C23°C
Soft Dry 24°C22°C20°C
Heating 23°C21°C19°C 
						

							32
11.5.3. 7 Minutes Time Save Control
•The compressor will start automatically if it has stopped for 7 minutes and the intake air temperature falls between the compres-
sor ON temperature (A) and compressor OFF temperature (B) during the period.
• This phenomenon is to reduce the built up humidity inside a room.
11.5.4. 60 Seconds Forced Operation
•Once the air conditioner is turned on, the compressor will not stop within 60 seconds in a normal operation although the intake air
temperature has reached the thermo-off temperature. However, force stop by pressing the OFF/ON operation button at the
remote control is permitted.
•The reason for the compressor to force operate at minimum 60 seconds is to allow the refrigerant oil run in a full cycle and return
back to the outdoor unit.
11.5.5. Starting current Control
•When the compressor, outdoor fan motor and indoor fan motor are simultaneously started, the indoor fan motor will start to oper-
ate at 1.6 second later.
•The reason of the difference is to reduce the starting current flow.
11.5.6. Freeze Preventive Control
• To protect indoor heat exchanger from freezing and to prevent higher volume of refrigerant in liquid form return to compressor.
• This control will activate when the temperature of indoor heat exchanger falls below 2°C continuously for more than 4 minutes.
• The current fan speed will change to freeze prevention speed after 70 seconds compressor on. When indoor pipe temperature
reaches certain temperature for 5 sec. the speed will be increased as in below figure.
• Compressor will turn off when indoor temperature falls below 2°C for more than 4 minutes. It will restart again when indoor heat
exchanger temperature rises to 10°C.
• Restart control (Time Delay Safety Control) will be applied in this control. 
						

							33
11.5.7. Dew Prevention control
• To prevent dew formation at indoor unit discharge area.
• This control will be activated if:-
- Cooling mode or Quiet mode.
- Remote Control setting temperature is less than 25°C.
- Fan speed is at Low or QLo.
- Room temperature is constant (±1°C) for 30 minutes.
- Compressor is continuously running.
• Fan speed and angle of horizontal louver (vertical airflow angle) will be adjusted accordingly in this control.
- Fan speed will be increased slowly if the unit is in quiet mode but no change in normal cooling mode.
- The angle of horizontal louver will be changed as below figure.
Note:
A = Normal operation angle of rotation
B = Dew prevention angle of rotation
Horizontal Louver Angle
During dew prevention, the horizontal louver angle in Auto-control are as below figure.
During dew prevention, the horizontal louver angle in Manual control are as below figure.
Operation mode Airflow direction auto-control Airflow direction manual control
Cooling, Soft Dry A 12° ~ 32°12°, 15°, 20°, 26°, 32°
B20° ~ 30°22°, 24°, 26°, 28°, 30° 
						

							34
11.5.8. 30 Minutes Time Save Control
• The compressor will start automatically if it has stopped for 30 minutes and the intake air temperature falls between the compres-
sor OFF temperature (A) and compressor ON temperature (B) during the period.
• This is to maintain the room temperature as set. Despite of this, it is to prevent a wrong judgement of intake air temperature due
to poor installation near the sensor area.
11.5.9. Compressor Overload Protection Control
Outdoor Fan Control
• If the temperature of the indoor heat exchanger rises to 51°C, outdoor fan stops. The outdoor fan restarts when the indoor heat
exchanger temperature falls to 49°C.
Compressor high pressure protection
• If the indoor heat exchanger becomes 65°C or more, the compressor will stop and restart automatically.
(Time Delay Safety Control - 4 minutes waiting).
• This is to reduce the pressure, as to reduce the indoor heat exchanger temp. Nevertheless, is to protect the compressor from
overload of too high temperature.
11.5.10. 4-Way Valve Control
• 4-way valve always on during Heating operation. (except deicing operation)
• When the unit is switched off by remote control during Heating operation, the 4-way valve stay at Heating position for 5 minutes.
• This is to prevent the refrigerant flow process sound for being occur.
11.5.11. Outdoor Fan Motor Control
• When compressor stops (reaches room temperature), outdoor fan will operate for 30 seconds (forced operation).
• This is to release the heat and to obtain the lowest pressure as fast as possible.
11.5.12. Hot Start Control
• Hot Start Control is to prevent cool air discharge into the room when heating operation start.
• When Heating operation starts, Indoor fan will not start until the indoor heat exchanger reaches 30°C as diagram shown.
• Hot start is completed when indoor heat exchanger rises to 39°C or operation over 4 minutes. 
						

							35
11.5.13. Anti Cold Draft Control
• This operation is to prevent the Cold Draft during Heating mode operation.
• The operation will start when compressor OFF (Thermo OFF) during Heating operation.
• For the first 30 sec. from compressor OFF (Thermo OFF), Indoor fan speed will operate accordingly to the Indoor heat
exchanger temperature as shown below:
• After 30 sec. from compressor OFF (thermo OFF), Indoor fan will run at SSLo speed only.
• Anti Cold Draft Control will stop when:
- Intake temperature < set temperature. (Time Delay Safety Control 4 minutes waiting is valid)
- 30 Minutes Time Save Control activates.  
						

							36
11.5.14. Deicing Control
Deice starts to prevent frosting at outdoor heat exchanger.
• Normal Deicing 
Deice operations detection commences after 30 minutes of Heating operation starts or 60 minutes after previous deice opera-
tion. If the TRS (Thermal Reed Switch) senses the outdoor piping temperature drops to -3°C (TRS CLOSE) or less for 50 sec.
continuously during compressor is in operation, deice will start.
(There is no detection during Outdoor Fan stops.)
• Overload Deicing
During heating operation, if the outdoor Fan OFF duration (due to overload control) is accumulated up to 60 minutes and after
compressor starts for 1 minutes, deicing starts.
• Deicing ends when
1. 12 minutes after deicing operation starts;
2. TRS senses the outdoor piping temperature rises to 4°C (TRS OPEN).
• Once deicing operation starts, it will not end for 60 seconds.
• After deicing operation, compressor stops for 30 seconds and 4-way valve stays at cooling position for 10 seconds.
Deicing will not end immediately as time delay (Td) is valid as shown below. 
						

							37 Normal Deicing Time Diagram
Overload Deicing Time Diagram 
						

							38
11.6. Indoor Fan Speed Control
• Indoor Fan Speed can be set using remote control.
11.6.1. Fan Speed Rotation Chart
11.6.2. Automatic Fan Speed Control
• When set to Auto Fan Speed, the fan speed is adjusted between maximum and minimum setting as shown in the table.
- Fan speed rotates in the range of Hi, Me and Lo-.
- Deodorizing Control will be activated.
Fan Speed (rpm) CS-A9EKH CS-A12EKH
S Hi 1300 1320
Hi 1210 1300
Me 1000 1120
H Lo 890 860
C Lo 830 800
Lo- 780 750
S Lo 750 700
SS Lo 300 300
Q S Hi 1200 1220
Q Hi 1110 1200
Q Me 900 1020
Q H Lo 790 810
Q Lo 730 700 
						

							39 • Auto Fan Speed during cooling operation:
1. Indoor fan will rotate alternately between off and on as shown in below diagram.
2. At the beginning of each compressor start operation, indoor fan will increase fan speed gradually for deodorizing purpose.
3. For the first time the compressor operate, indoor fan will be switched to Hi fan speed from Lo- after 70 seconds from the
start of compressor. This cause the room temperature to achieve the setting temperature quickly.
4. During compressor stop, indoor fan will operate at Lo for the beginning 3 minutes to prevent higher volume of refrigerant in
liquid form returning to the compressor.
5. For the resume of compressor operation, indoor fan will operate at Me fan speed to provide comfort and lesser noise envi-
ronment, after 70 seconds from the restart of compressor.
• Auto Fan Speed during Soft Dry operation:
1. Indoor fan will rotate alternately between off and Lo-.
2. At the beginning of each compressor start operation, indoor fan will increase fan speed gradually for deodorizing purpose.
3. When compressor at turn off condition for 6 minutes, indoor fan will start fan speed at Lo- to circulate the air in the room.
This is to obtain the actual reading of intake air temperature. 
						

							40 • Auto Fan Speed during Heating operation.
1. Indoor fan will rotate in the range of SLo → Me according to the heat exchanger temperature.
11.6.3. Manual Fan Speed Control
• Manual fan speed adjustment can be carried out by using the Fan Speed selection button at the remote control.
• There are 3 types of fan speed settings: Lo, Me, Hi.
11.7. Outdoor Fan Speed Control
•There is only one speed for outdoor fan motor.
• When the air conditioner is turned on, the compressor and the outdoor fan will operate simultaneously.
• Likewise, both compressor and outdoor fan will stop at the same time if the unit is turned off.
11.8. Vertical Airflow Direction Control
11.8.1. Auto Control
• When the vertical airflow direction is set to Auto using the
remote control, the louver swings up and down as shown in
the diagram.
• When stop operation using the remote control, the discharge
vent is reset, and stop at the closing position.
• During Cooling operation or Soft Dry operation, indoor fan
motor may stop to rotate at certain periods. At that condition,
the louver will stop swinging and rest at the upper limit.