Panasonic CU-2E15PBD / CU-2E18PBD Service Manual ▷ View online
29
13.8 Deice Control
When outdoor pipe temperature and outdoor air temperature is low, deice operation starts where indoor fan
motor and outdoor fan motor stop, indoor unit horizontal vane close and operation LED blink with compressor ON.
13.9 Time Delay Safety Control (Restart Control)
The compressor will not restart within three minutes after compressor is stopped.
This control is not applicable if the power supply reset or after deice condition.
13.10 30 seconds Force Operation
Once the compressor starts operation, it will not stop its operation for 30 seconds in order to cycle back
compressor oil.
However, it can be stopped using remote control or Auto OFF/ON button at indoor unit.
13.11 Total Current Control
By referring to table below, during normal (default) operation, the running current refer to Hi values and during
Power Save Mode, the running current refer to Lo values. (not applicable for 2E18/2E15)
When the outdoor unit total running current (AC) exceeds X value, compressor frequency will decrease.
If the running current does not exceed X value for 5 seconds, compressor frequency will increase.
However, if total outdoor unit running current exceeds Y value, compressor will be stopped immediately for
3 minutes.
Operation Mode
CU-2E18PBD CU-2E15PBD
X (A)
Y (A)
X (A)
Y (A)
Cooling/Soft Dry (A)
Hi 10.12 12.54 10.12 12.54
Lo
- - - -
Cooling/Soft Dry (B)
Hi 8.79 12.54 8.79 12.54
Lo
- - - -
Heating
Hi 11.04 12.54 11.04 12.54
Lo
- - - -
13.12 IPM (power transistor) Protection Control
Overheating Prevention Control
o
If IPM temperature rises to 80°C, outdoor fan speed will be increased.
o
When the IPM temperature rises to 95°C, compressor operation will stop immediately.
o
Compressor operation restarts when temperature decreases to 90°C.
o
If IPM temperature detected less than -30°C, IPM is judged as open circuit (“F96” is indicated).
DC peak current control
o
When IPM DC current exceeds set value of 30.0 ± 3.0 A, the compressor will stop.
o
If the DC peak current detected within 30 seconds after operation starts, compressor will restart after
1 minute.
o
If the DC peak current detected 30 seconds or more after operation starts, compressor will restart after
2 minutes.
o
Within 30 seconds after compressor restarts, if the DC peak current is exceeded set value continuously for
7 times, all indoor and outdoor relays will be cut off (“F99” is indicated).
Error reset can be done by power supply reset.
30
13.13 Compressor Protection Control (Gas leak detection control 1)
Control start conditions
o
For 5 minutes, the compressor continuously operates and total current is low.
o
During Cooling or Soft Dry operation:
Indoor intake temperature — indoor piping temperature is below 4°C.
o
During Heating operation:
Indoor pipe temperature — indoor intake temperature is below 3°C.
o
Not during deice control.
o
Compressor ON with maximum frequency.
Control
content
o
Compressor stops (and restart after 3 minutes)
o
If the conditions above happen 4 times within 60 minutes, the unit will stop operation (“F91” is indicated).
13.14 Compressor Protection Control (Gas leak detection control 2)
This control detect gas leakage condition to prevent compressor damage.
Control start condition
o
All connected indoor units capability supply ON.
o
Compressor ON with maximum frequency.
o
Not during annual cooling.
o
Compressor discharge temperature high.
Control
content
o
Compressor OFF during this control (“F91” is memorized in EEPROM)
o
If the above conditions happen 2 times within 60 minutes, indoor units’ Timer LED will blinks (“F91” is
indicated at all indoor units)
13.15 Valve close detection control
This control detects 3-way valve close condition to prevent damage to refrigerant cycle.
Start
conditions:
o
For all connected indoor units, if Indoor intake temperature — indoor piping temperature are between -2°C
and 2°C continuously for 5 minutes after compressor ON at first cooling operation.
o
The first cooling operation is defined as cooling operation is ON for less than 8 minutes after new installation
or after pump down.
Control
content
o
During this control, compressor stop, indoor units’ Timer LED will blink. (“F91” is indicated at indoor units)
Error reset can be done by power supply reset or reset by using remote control.
13.16 Compressor discharge high pressure protection control
This control protect by using high pressure switch during operation.
Start
conditions
o
High pressure switch is activated (from normally close to open) when outdoor operation mode is cooling or
heating during compressor running.
Control 1 content
o
Compressor stop when high pressure switch is opened and restart after high pressure switch closed. If this
condition happen 4 times within 30 minutes, “F94” is indicated.
o
After 30 minutes, counter is reset if this condition does not happen for 4 times.
Control 1 stop conditions
o
Power supply reset
o
Reset by using remote control
31
14. Servicing
Mode
14.1 Pump down operation
Operate the pump down process according to the following procedure
o
Confirm the valve on the liquid side and gas side are open.
o
Short the CN-PUMP button on the Service PCB inside the outdoor unit for more than 5 seconds. Pump down
(cooling) operation is performed for 15 minutes.
o
Set the liquid side 3 way valve to close position and wait until the pressure gauge indicates 0.01MPa
(0.1kg/cm
2
G).
o
Immediate set the gas side valve to close position and then Short the CN-PUMP button to stop the pump
down operation.
NOTE: Pump down operation will stop automatically after 15 minutes if CN-PUMP button is not shorted again. Pump
down operation is not started within 3 minutes after compressor is stopped.
down operation is not started within 3 minutes after compressor is stopped.
14.2 Cooling only function
The unit capable to limit the operation mode to Cooling Mode only (Heating mode disabled) by switch to ON
(SW-COOLING) at outdoor main PCB before power supply ON.
This function prevent wrong operation during the unit installed in server room.
This function could be disabled again by switch to OFF (SW-COOLING) at outdoor main PCB before power
supply ON.
32
15. Troubleshooting
Guide
15.1 Self Diagnosis Function
Click on the first or last page to see other CU-2E15PBD / CU-2E18PBD service manuals if exist.