Pressure Equalizing Control - Daikin FTX20K(2)V1B Service Manual

Control Specification
3.11.1 Fully Closing with Power ON
The electronic expansion valve is initialized when turning on the power. The opening position is
set and the pressure is equalized.

3.11.2 Pressure Equalizing Control

When the compressor is stopped, the pressure equalizing control is activated. The electronic
expansion valve opens and the pressure is equalized.
3.11.3 Opening Limit Control
The maximum and minimum opening of the electronic expansion valve are limited.
Maximum opening (pulse)
Minimum opening (pulse)
The electronic expansion valve is fully closed when cooling operation stops, and is controlled at
a fixed opening during defrosting.
3.11.4 Starting Operation Control
The electronic expansion valve opening is controlled when the operation starts, thus preventing
superheating or liquid compression.
3.11.5 Control when the Frequency Changes
When the target discharge pipe temperature control is active, if the target frequency changes to
a specified value in a certain time period, the target discharge pipe temperature control is
canceled and the target opening of the electronic expansion valve is changed according to the
frequency shift.
3.11.6 High Discharge Pipe Temperature Control
When the compressor is operating, if the discharge pipe temperature exceeds a certain value,
the electronic expansion valve opens and the refrigerant runs to the low pressure side. This
procedure lowers the discharge pipe temperature.
37
20/25/35 class 50/60/71 class
470 480
52 52
SiBE041525F
Functions and Control