Daikin F-Series Service Manual page 65

Control Specification
3.11.1 Fully Closing with Power ON
Initialize the electronic expansion valve when turning on the power, set the opening position and
develop pressure equalizing.
3.11.2 Pressure Equalization Control
When the compressor is stopped, open and close the electronic expansion valve and develop
pressure equalization.
3.11.3 Opening Limit
Outline Limit a maximum and minimum opening of the electronic expansion valve.
Detail
The electronic expansion valve is fully closed in the room where cooling is stopped and is
opened with fixed opening during defrosting.
3.11.4 Starting Operation Control
Control the electronic expansion valve opening when the system is starting, and prevent the
system to be super heated or moistened.
3.11.5 High Temperature of the
When the compressor is operating, if the discharge pipe temperature exceeds a certain value,
open the electronic expansion valve and remove the refrigerant to the low pressure side and
lower discharge temperature.
3.11.6 Disconnection of the
Outline Disconnection of the discharge pipe thermistor is detected by comparing the discharge pipe
temperature with the heat exchanger temperature. If any is disconnected, open the electronic
expansion valve according to the outdoor air temperature and the operating frequency, and
operate for 9 minutes, and then stop.
After 3 minutes of waiting, the compressor restarts and the same process is carried out again. If
the disconnection is detected 4 times in succession, then the system will be down.
When the compressor runs for 60 minutes without any error, the error counter will reset itself.
Detail Detect Disconnection
When the 630-seconds timer for open control is over, the following adjustment must be made.
1. When the operation mode is cooling
2. When the operation mode is heating (only for heat pump model)
54
A maximum electronic expansion valve opening : 480 pulses (71-90FVMA : 450 pulses)
A minimum electronic expansion valve opening : 54 pulses (71-90FVMA : 75 pulses)
Discharge Pipe
Discharge Pipe Thermistor
When the following condition is fulfilled, the discharge pipe thermistor disconnection is
ascertained.
Discharge pipe temperature +6°C < outdoor heat exchanger temperature
When the following condition is fulfilled, the discharge pipe thermistor disconnection is
ascertained.
Discharge pipe temperature +6°C < indoor heat exchanger temperature
Si04-703A
Function and Control