Panasonic Cs A7dkd Cs A9dkd Cs A12dkd Repair Manual

							8.3.1. Soft Dry Operation Time Diagram
8.3. Soft Dry Operation
 • Soft Dry operation can be set using remote control.
 • Soft Dry operation is applied to dehumidify and to perform a gentle cooling to the room.
 • This operation starts when the intake air temperature sensor reaches the setting temperature on the remote control.
 • W hen operation begins, Soft Dry will be switched “ON” for a maximum 10 minutes, then Soft Dry operation will be turned “OFF”
for a minimum 6 minutes. After that, the Soft Dry operation will be “ON” and “OFF” based on the setting temperature as shown
in below figure.
 • However after 3 minutes of compressor off, duringSoft Dry “OFF” (within 6 minutes Soft Dry restart control), the indoor unit will
start to operate at normal Cooling mode if the intake temperature is higher than Cooling “ON” point.
21
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							8.4. Automatic Operation
 • Automatic operation can be set using remote control.
 • This operation starts to operate with indoor fan at SLo speed for 25 seconds to judge the intake air temperature.
 • After judged the temperature, the operation mode is determined by referring to the below standard.
 • Then, the unit start to operate at determined operation mode, until it is switched off using remote control, with the setting
temperature as shown in below table.
 • Operation mode will be determine again for judgement after 1 hour of operation, if the room temperature reaches to set
temperature and compressor off time is over7 minutes 30 seconds continuously.
The present operation mode will be continued, if the room temperature does not reach to set temperature (Compressor keeps running)
eventhough after 1 hour from automatic operation mode started.
PresentJudgementNext Mode
ModeCoolingSoft DryHeating
OO
Cooling23°CCooling(Judgement:Not Applicable(Judgement:
Heating23°C & Above)Below 23°C)
OO
Soft Dry20°CSoft DryNot Applicable(Judgement:(Judgement:
Heating20°C & Above)Below 20°C)
OO
HeatingCooling(Judgement:Not Applicable(Judgement:
25°CHeatingAbove 25°C)25°C & below)
Automatic Set Temperature
Refer as below.
 • 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”.
OperationHi(Standard)Lo
(+2°C)(±0°C)(-2°C)
Cooling27°C25°C23°C
Soft Dry24°C22°C20°C
Heating23°C21°C19°C
 • 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.
22
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							 • The operation mode judging temperature and standard setting temperature canbe increased by 2°C permanently, by open the
circuit of JX1 at indoor electronic controller.
8.5. Operation Control
8.5.1. 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 balancethe pressure inside the refrigerant cycle.
8.5.2. 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) orless for continuous 2 minutes,compressor will stop and
restart automatically.
 • Time Delay Safety Control isactivated before the compressor restart.
sT = Intake air temperature - Indoor heat exchanger temperature
 • This is to prevent compressor from rotate reversely when there is an instantaneous power failure.
23
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							(For 8.5.3. to 8.5.7. information applies only to Cooling and Soft Dry Operation)
8.5.3. 7 Minutes Time Save Control
 • The compressor will startautomatically if it has stopped for 7 minutes and the intake air temperature falls between the
compressor ON temperature (A) and compressor OFF temperature (B) during the period.
 • This phenomenon is to reduce thebuilt up humidity inside a room.
8.5.4. 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.
8.5.5. Starting Current Control
 • When the compressor, outdoor fan motor and indoor fan motor are simultaneously started, the indoor fan motor will start to
operate at 1.6 second later.
 • The reason of the difference isto reduce thestarting current flow.
8.5.6. Anti-Freezing Control
 • If the temperature of the indoor heat exchanger falls below 2°C continuously for 4 minutes or more, the compressor turns off.
The fan speed setting remains the same.
 • This phenomenon is to protect the indoor heat exchanger from freezing and to prevent higher volume of refrigerant in liquid form
returning to the compressor.
 • Compressor will restart again when the indoor heat exchanger temperature rises to 10°C (Recovery).
 • Restart control (Time DelaySafety Control)will be applied in this Control if the recovery time is too short.
24
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							(For 8.5.8. to 8.5.14. information applies only to Heating Operation)
8.5.7. Anti-Dew Formation Control
 • Purpose is to prevent dew formation on indoor unit air discharge area.
 • When room temperature is constant (±1°C) the following conditions occur for 30 minutes continuously, anti-dew formation will
activate:
 − Remote Control setting temperature is less than 25°C.
 − Compressor is on.
 − Cooling operation mode.
 − Indoor Fan motor operate at Low fan speed (CLo, Lo- or QLo).
 • This control is cancelled immediately when abovecondition is changed, or Powerful button is pressed.
 • Anti-Dew formation is control by:
 1. CLo fan is changed to HLo fan.
 2. QLo fan is changed to HLo fan.
8.5.8. 30 Minutes Time Save Control
 • The compressor will startautomatically if it has stopped for 30 minutes and the intake air temperature falls between the
compressor 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.
25
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							8.5.9. 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 ormore, the compressor willstop 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.
8.5.10. 4-Way Valve Control
 • 4-wayvalvealways onduring Heating operation. (except deicing operation)
 • When the unit is switched off by remote control during Heatingoperation, the 4-way valve stayat Heating position for 5 minutes.
 • This is to prevent the refrigerantflow processsound for being occur.
8.5.11. Outdoor Fan Motor Control
 • When compressor stops (reaches room temperature), outdoor fanwill operate for 30 seconds (forced operation).
 • This is to release the heat and to obtain the lowest pressure as fast as possible.
26
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							8.5.12. 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.
8.5.13. 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 DelaySafety Control 4minutes waiting is valid)
 − 30 Minutes Time Save Control activates.
27
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							8.5.14. 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
operation. If the TRS (Thermal Reed Switch) senses the outdoorpiping temperature drops to -3°C (TRS CLOSE) or less for
50 sec. continuously during compressor isin 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).
Deicing will not end immediately astime delay(Td) is valid as shown below.
 • Once deicing operation starts, it will not end for 60 seconds.
 • After deicing operation, compressor stops for 30 seconds and 4-wayvalve stays at cooling position for 10 seconds.
28
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							Normal Deicing Time Diagram
Overload Deicing Time Diagram
29
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD / 
						

							8.6. Indoor Fan Speed Control
 • Indoor Fan Speed can be set using remote control.
8.6.1. Fan Speed Rotation Chart
Fan Speed (rpm)CS-A7DKDCS-A9DKDCS-A12DKD
SHi122012701310
Hi105011601280
Me9209601120
HLo840840960
CLo780780880
Lo-750750850
SLo700700750
SS Lo300300300
QSHi112011701210
QHi95010601180
QMe8208601020
QHLo770770890
QLo680680780
8.6.2. 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.
30
CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12D KD CU-A12D KD /