Daikin FTKS20DVMW(L), Service Manual

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SiENBE04-507A Control Specification
Function and Control 73
3.12 Malfunctions
3.12.1 Sensor Malfunction Detection
Sensor malfunction may occur in the thermistor.
Relating to Thermistor Malfunction
1. Outdoor heat exchanger thermistor
2. Discharge pipe thermistor
3. Fin thermistor
4. Outdoor air thermistor
3.12.2 Detection of Overload and Over Current
Outline
In order to protect the inverter, detect an excessive output current, and for protecting
compressor, monitor the OL operation.
Detail
„
If the OL (compressor head) temperature exceeds 120°C (depending on the model),
the compressor gets interrupted.
„
If the inverter current exceeds 22 A, the compressor gets interrupted too.
3.12.3 Insufficient Gas Control
Outline
There are three ways of control to detect insufficient gas.
I Detecting by power consumption
If the power consumption is below the specified value and the frequency is higher than the
specified frequency, it is regarded as insufficient gas.
The power consumption is weak comparing with that in the normal operation when gas is
insufficient, and gas insufficiency is detected by checking a power consumption.
II Detecting by discharge pipe temperature
If the discharge temperature is higher than the target discharge pipe temperature, and the
electronic expansion valve is fully open (480 pulses) more than the specified time, it is regarded
as insufficient gas.
III Detecting by the difference of temperature
If the difference between inhale and exhale temperature is smaller than the specified value, it is
regarded as insufficient gas.
P
o
w
e
r consumption
Insufficient gas zone
55 Hz Frequency
(R2834)
(R1 3 91)
G as in su fficient
zone