Malfunctions - Daikin F-Series Service Manual

SiBE04-705

3.12 Malfunctions

3.12.1 Sensor Malfunction Detection
Sensor malfunction may occur either in the thermistor or current transformer (CT) system.
Relating to Thermistor Malfunction
1. Outdoor heat exchanger thermistor
2. Discharge pipe thermistor
3. Fin thermistor
4. Outside air thermistor
Relating to CT Malfunction
When the output frequency is more than 55 Hz and the input current is less than 0.5A, carry out
abnormal adjustment.
3.12.2 Detection of
Outline In order to protect the inverter, detect an excessive output current, and for protecting
compressor, monitor the OL operation.
Detail
3.12.3 Insufficient Gas Control
Outline If a power consumption is below the specified value in which the frequency is higher than the
specified frequency, it must be regarded as gas insufficient.
In addition to such conventional function, if the discharge temperature is higher than the target
discharge pipe temperature, and the electronic expansion valve is fully open (450 pulses) more
than the specified time, it is considered as an insufficient gas.
With the conventional function, a 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.
When operating with insufficient gas, although the rise of discharge pipe temperature is great
and the electronic expansion valve is open, it is presumed as an insufficient gas if the discharge
pipe temperature is higher than the target discharge pipe temperature.
Refer to "Insufficient Gas" on page 150 for detail.
Function and Control
Overload and
If the OL (compressor head) temperature exceeds 120~130°C (depending on the
model), the compressor gets interrupted.
If the inverter current exceeds 30 A, the compressor gets interrupted too.
Over Current
Insufficient gas zone
55 Hz Frequency
Gas insufficient
zone
Control Specification
(R2834)
(R1391)
55