Daikin B-Series Service Manual page 83

Control Specification
3.13.3 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.
Detail Judgment by Input Current
When an output frequency is exceeds 55 Hz and the input current is less than specified value,
the adjustment is made for insufficient gas.
Judgment by Discharge Pipe Temperature
When discharge pipe temperature is 20°C higher than target value and the electronic expansion
value opening is 450 plus (max.), the adjustment is made for insufficient gas.
Refer to "Insufficient Gas" on page 139 for details.
72
Insufficient gas zone
55 Hz Frequency
(R2834)
Gas insufficient
zone
(R1391)
Si04-306E
Function and Control