Compressor Protection Control (Gas Leak Detection Control 1); Compressor Protection Control (Gas Leak Detection Control 2); Valve Close Detection Control; Compressor Discharge High Pressure Protection Control - Panasonic CU-4E23QBR Service Manual

14.13 Compressor Protection Control (Gas Leak Detection Control 1)


Control start conditions
For 5 minutes, the compressor continuously operates and total current is low.
o
During Cooling or Soft Dry operation:
o
Indoor intake temperature — indoor piping temperature is below 4°C.
During Heating operation:
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Indoor pipe temperature — indoor intake temperature is below 3°C.
Not during deice control.
o
Compressor ON with maximum frequency.
o

Control content
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).
o

14.14 Compressor Protection Control (Gas Leak Detection Control 2)


This control detect gas leakage condition to prevent compressor damage.

Control start condition
All connected indoor units capability supply ON.
o
Compressor ON with maximum frequency.
o
Not during annual cooling.
o
Compressor discharge temperature high.
o

Control content
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
o
indicated at all indoor units)

14.15 Valve Close Detection Control


This control detects 3-way valve close condition to prevent damage to refrigerant cycle.

Start conditions:
For all connected indoor units, if Indoor intake temperature — indoor piping temperature are between -2°C
o
and 2°C continuously for 5 minutes after compressor ON at first cooling operation.
The first cooling operation is defined as cooling operation is ON for less than 8 minutes after new installation
o
or after pump down.

Control content
During this control, compressor stop, indoor units' Timer LED will blink. ("F91" is indicated at indoor units)
o

Error reset can be done by power supply reset or reset by using remote control.

14.16 Compressor Discharge High Pressure Protection Control


This control protect by using high pressure switch during operation.

Start conditions
High pressure switch is activated (from normally close to open) when outdoor operation mode is cooling or
o
heating during compressor running.

Control 1 content
Compressor stop when high pressure switch is opened and restart after high pressure switch closed. If this
o
condition happen 4 times within 30 minutes, "F94" is indicated.
After 30 minutes, counter is reset if this condition does not happen for 4 times.
o

Control 1 stop conditions
Power supply reset
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Reset by using remote control
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