Panasonic CS-E7PKDW / CS-E9PKDW / CS-E12PKDW / CS-E15PKDW / CS-E18PKDW / CS-E24PKDW / CU-E7PKD / CU-E9PKD / CU-E12PKD / CU-E15PKD / CU-E18PKD / CU-E24PKD Service Manual ▷ View online
81
14.2 Protection Control For Cooling & Soft Dry Operation
14.2.1 Outdoor Air Temperature Control
The compressor operating frequency is regulated in accordance to the outdoor air temperature as shown in the
diagram below.
This control will begin 1 minute after the compressor starts.
Compressor
frequency will adjust base on outdoor air temperature.
14.2.2 Cooling Overload Control
Detects the Outdoor pipe temperature and carry out below restriction/limitation (Limit the compressor Operation
frequency).
The compressor stop if outdoor pipe temperature exceeds 61°C (E7 ~ 15PK) and 63°C (E18PK).
If the compressor stops 4 times in 20 minutes, Timer LED blinking (F95 indicated: outdoor high pressure rise
protection).
14.2.3 Freeze Prevention Control 1
When indoor heat exchanger temperature is lower than 0°C continuously for 6 minutes, compressor will stop
operating.
Compressor will resume its operation 3 minutes after the indoor heat exchanger is higher than 5°C.
At the same time, indoor fan speed will be higher than during its normal operation.
If indoor heat exchanger temperature is higher than 5°C for 5 minutes, the fan speed will return to its normal
operation.
14.2.4 Freeze Prevention Control 2
Control start conditions
o
During Cooling operation and soft dry operation
During thermo OFF condition, indoor intake temperature is less than 10°C or
Compressor stops for freeze prevention control
o
Either one of the conditions above occurs 5 times in 60 minutes.
Control
contents
o
Operation
stops
o
Timer LED blinks and “H99” indicated
14.2.5 Dew Prevention Control 1
To prevent dew formation at indoor unit discharge area.
This control will be activated if:
o
Outdoor air temperature and Indoor pipe temperature judgment by microcontroller is fulfilled.
o
When Cooling or Dry mode is operated more than 20 minutes or more.
This control stopped if:
o
Compressor
stopped.
o
Remote control setting changed (fan speed / temperature).
o
Outdoor air temperature and indoor intake temperature changed.
Fan speed will be adjusted accordingly in this control.
82
14.2.6 Odor
Cut
Control
To reduce the odor released from the unit.
o
Start
Condition
AUTO FAN Speed is selected during COOL or DRY operation.
During freeze prevention control and timer preliminary operation, this control is not applicable.
o
Control
content
Depends on compressor conditions:
Compressor
OFF
→
Compressor ON.
The indoor unit fan stops temporarily and then starts to blow at minimum airflow for 30 seconds.
Compressor
ON
→
Compressor OFF.
The indoor unit fan stops for 90 seconds and then blows at minimum airflow for 20 seconds.
14.3 Protection Control For Heating Operation
14.3.1 Intake Air Temperature Control
Compressor will operate at limited freq., if indoor intake air temperature is 30°C or above.
14.3.2 Outdoor Air Temperature Control
The Max current value is regulated when the outdoor air temperature rise above 16°C (E7 ~ 15PK) and 14°C
(E18PK) in order to avoid compressor overloading.
14.3.3 Overload Protection Control
The compressor operating frequency is regulated in accordance to indoor heat exchanger temperature as shown
below.
If the heat exchanger temperature exceeds 60°C, compressor will stop.
14.3.4 Low Temperature Compressor Oil Return Control
In heating operation, if the outdoor temperature falls below -10°C when compressor starts, the compressor
frequency will be regulated up to 600 seconds.
14.3.5 Cold Draught Prevention Control
When indoor pipe temperature is low, cold draught operation starts where indoor fan speed will be reduced.
14.3.6 Deice
Operation
When outdoor pipe temperature and outdoor air temperature is low, deice operation start where indoor fan motor
and outdoor fan motor stop and operation LED blinks.
83
15. Protection Control (E24PK)
15.1 Protection Control For All Operations
15.1.1 Time Delay Safety Control
1 The compressor will not start for three minutes after stop of operation.
2 This control is not applicable if the power supply is cut off and on again or after 4-way valve deices condition.
2 This control is not applicable if the power supply is cut off and on again or after 4-way valve deices condition.
15.1.2 Total Running Current Control
1 When the outdoor unit total running current (AC) exceeds X value, the frequency instructed for compressor
operation will be decreased.
2 If the running current does not exceed X value for five seconds, the frequency instructed will be increased.
3 However, if total outdoor unit running current exceeds Y value, compressor will be stopped immediately for
3 However, if total outdoor unit running current exceeds Y value, compressor will be stopped immediately for
3 minutes.
E24PK
Operation Mode
X (A)
Y (A)
Cooling/Soft Dry (A)
15.03
19.02
Cooling/Soft Dry (B)
13.63
19.02
Cooling/Soft Dry (C)
15.03
19.02
Heating 13.35
19.02
4 The first 30 minutes of cooling operation, (A) will be applied.
15.1.3 IPM (Power transistor) Prevention Control
A. Overheating Prevention Control
1 When the IPM temperature rises to 110°C, compressor operation will stop immediately.
2 Compressor operation restarts after three minutes the temperature decreases to 95°C.
3 If this condition repeats continuously 4 times within 20 minutes, timer LED will be blinking (“F96” is indicated).
2 Compressor operation restarts after three minutes the temperature decreases to 95°C.
3 If this condition repeats continuously 4 times within 20 minutes, timer LED will be blinking (“F96” is indicated).
B. DC Peak Current Control
o
When electric current to IPM exceeds set value of 30.0 ± 5.0 A, the compressor will stop operate. Then,
operation will restart after three minutes.
o
If the set value is exceeded again more than 30 seconds after the compressor starts, the operation will
restart after one minute.
o
If the set value is exceeded again within 30 seconds after the compressor starts, the operation will restart
after one minute. If this condition repeats continuously for seven times, all indoor and outdoor relays will be
cut off, timer LED will be blinking (“F99” is indicated).
cut off, timer LED will be blinking (“F99” is indicated).
84
15.1.4 Compressor
Overheating Prevention Control
Instructed frequency for compressor operation will be regulated by compressor discharge temperature. The changes
of frequency are as below figure.
If compressor discharge temperature exceeds 112°C, compressor will be stop, occurs 4 times per 20 minutes, timer
LED will be blinking (“F97” is to be confirmed).
of frequency are as below figure.
If compressor discharge temperature exceeds 112°C, compressor will be stop, occurs 4 times per 20 minutes, timer
LED will be blinking (“F97” is to be confirmed).
15.1.5 Low Pressure Prevention Control (Gas Leakage Detection)
a. Control start conditions
o
For 5 minutes, the compressor continuously operates and outdoor total current is between 1.88A and 2.85A
(Cooling), 2.85A and 3.57A (Heating).
o
During Cooling and Soft Dry operations:
Indoor suction temperature - indoor piping temperature is below 4°C.
o
During Heating operations :
Indoor piping temperature - indoor suction is under 5°C.
b. Control contents
o
Compressor stops (and restart after 3 minutes).
o
If the conditions above happen 2 times within 20 minutes, the unit will:
- Stop operation.
- Timer LED blinks and “F91” indicated.
- Timer LED blinks and “F91” indicated.
15.1.6 Low
Frequency
Protection Control 1
When the compressor operate at frequency lower than 20 Hz continued for 20 minutes, the operation frequency
will be changed to 21 Hz for 2 minutes.
15.1.7 Low
Frequency
Protection Control 2
When all the below conditions comply, the compressor frequency will change to lower frequency.
Temperature, T, for:
Cooling/Soft Dry
Heating
Indoor intake air (°C)
T < 14 or T 30
T < 14 or T 28
Outdoor air (°C)
T < 13 or T 38
T < 4 or T 24
Indoor heat exchanger (°C)
T < 30
T < 0
Click on the first or last page to see other CS-E7PKDW / CS-E9PKDW / CS-E12PKDW / CS-E15PKDW / CS-E18PKDW / CS-E24PKDW / CU-E7PKD / CU-E9PKD / CU-E12PKD / CU-E15PKD / CU-E18PKD / CU-E24PKD service manuals if exist.