Cooling Overload Control; Freeze Prevention Control; Dew Prevention Control; Protection Control For Heating Operation - Panasonic CS-E18NKUA Service Manual

13.2.2

Cooling Overload Control

Pipe temperature limitation / restriction.
Detects the outdoor pipe temperature and carry out restriction / limitation below (Limit the compressor
o
operation frequency)
The compressor stops if outdoor pipe temperature exceeds 145.4°F.
o
If the compressor stops 4 times in 20 minutes, Timer LED blinks ("F95" indicated: Outdoor high pressure rise
o
protection)
13.2.3

Freeze Prevention Control 1

When indoor heat exchanger temperature is lower than 32°F continuously for 6 minutes, compressor will stops
operation.
Compressor will resume its operation 3 minutes after the indoor heat exchanger is higher than 41.0°F.
At the same time, indoor fan speed will be higher than during its normal operation.
If the indoor heat exchanger temperature is higher than 55.4°F for 5 minutes, the fan speed will return to its
normal operation.
13.2.4 Freeze Prevention Control 2
Control start conditions
During Cooling operation and soft dry operation
o
During thermo OFF condition, indoor intake temperature is less than 50.0°F or
Compressor stops for freeze prevention control
Either one of the conditions above occurs 5 times in 60 minutes.
o
Control contents
Operation stops
o
Timer LED blinks and "H99" indicated
o
13.2.5

Dew Prevention Control 1

To prevent dew formation at indoor unit discharge area.
This control will be activated if:
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.
o
This control stopped if:
Compressor stopped.
o
Remote control setting changed (fan speed / temperature).
o
Outdoor air temperature and indoor intake temperature changed.
o
Fan speed, angle of louver (vertical airflow angle) will be adjusted accordingly in this control.
1. Fan speed will be increased slowly when control is activated until predetermine value.
Compressor frequency will be regulated accordingly.
13.2.6

Protection Control For Heating Operation

13.2.6.1 Intake Air Temperature Control
Compressor will operate at limited freq., if indoor intake air temperature is 86.0°F or above.
13.2.6.2 Outdoor Air Temperature Control
The Max current value is regulated when the outdoor air temperature rise above 57.2°F in order to avoid
compressor overloading.
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