Panasonic CS-E12RB4UW Service Manual page 50

13.3.3 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 (140°F), compressor will stop.
13.3.4 Low Temperature Compressor Oil Return Control

In heating operation, if the outdoor temperature falls below -10°C (14°F) when compressor starts, the
compressor frequency will be regulated up to 600 seconds.
13.3.5 Cold Draught Prevention Control

When indoor pipe temperature is low, cold draught operation starts where indoor fan speed will be reduced.
13.3.6 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.
13.3.7 Pump down Operation by CN-S

A convenience method to activate pump down operation.

Control start condition:
During power standby condition, short CN-S continuously between 1 second and 10 seconds.
o

Control stop condition:
480 seconds after pump down operation starts.
o
CN-S is shorted again during pump down operation.
o
OFF
60°C (140°F)
Frequency Reduce
55°C (131°F)
Frequency Limited
49°C (120.2°F)
Free
Indoor Heat
Exchanger Temp.
50
52°C (125.6°F)
46°C (114.8°F)