Panasonic CS-A18EKH Service Manual page 32

11.5.4. Anti-Freezing Control
• If the temperature of the indoor heat exchanger falls below 2°C continuously for 4 minutes or more, the compressor turns off.
The fan speed setting remains the same.
• This phenomenon is to protect the indoor heat exchanger from freezing and to prevent higher volume of refrigerant in liquid form
returning to the compressor.
• Compressor will restart again when the indoor heat exchanger temperature rises to 10°C (Recovery).
• Restart control (Time Delay Safety Control) will be applied in this Control if the recovery time is too short.
11.5.5. Compressor Reverse Rotation Protection Control
• If the compressor is operating continuously for 5 minutes or longer and the temperature difference between intake air and indoor
heat exchanger is 2.5°C or less for continuous 2 minutes, compressor will stop and restart automatically.
• Time Delay Safety Control is activated before the compressor restart.
▲ T = Intake air temperature - Indoor heat exchanger temperature
• This is to prevent compressor from rotate reversely when there is an instantaneous power failure.
11.5.6. Starting Current Control
• When the compressor, outdoor fan motor and indoor fan motor are simultaneously started, the indoor fan motor will start to oper-
ate at 1.6 second later.
• The reason of the difference is to reduce the starting current flow.
11.5.7. Anti-Dew Formation Control
• Purpose is to prevent dew formation on indoor unit air discharge area.
• When room temperature is constant (±1°C) the following conditions occur for 30 minutes continuously, anti-dew formation will
activate:
- Remote Control setting temperature is less than 25°C.
- Compressor is on.
- Cooling operation mode.
-
Indoor Fan motor operate at Low fan speed or QLo.
• This control is cancelled immediately when above condition is changed.
• Anti-Dew formation is control by:
1. Increasing Air Flow Volume
a. Lo fan speed
Lo fan speed is changed to Lo+ after 30 min to prevent dew formation.
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