Daikin 2MXS-W Series Service Manual page 119

SiUS122226E
4.14.1 Initialization as Power Supply On
The electronic expansion valve is initialized (fully closed) when the power is turned on. Then, the
valve opening position is set and the pressure is equalized.
4.14.2 Pressure Equalizing Control
When the compressor is stopped, the pressure equalizing control is activated. The electronic
expansion valve opens, and develops the pressure equalization.
4.14.3 Opening Limit Control
The maximum and minimum opening of the electronic expansion valve are limited.
Max. valve opening (pulse)
Min. valve opening (pulse)
The electronic expansion valve is fully closed in the room where cooling is stopped and is opened
at a fixed degree during defrosting.
4.14.4 Starting Operation Control/Changing Operation Room
The electronic expansion valve opening is controlled when the operation starts, thus preventing
superheating or liquid compression.
4.14.5 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 period of time, the target discharge pipe temperature control is canceled
and the target opening of the electronic expansion valve is changed.
4.14.6 Oil Recovery Function
Outline
The electronic expansion valve opening for the room not in operation is set as to open for a certain
time at a specified interval so that the oil for the room not in operation may not be accumulated.
Details During cooling operation, the electronic expansion valve for the room not in operation is opened
every 1 hour by 80 pulses for specified time.
4.14.7 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.
Part 4 Functions and Control
2/3/4MXS 5MXS
450 480
64 60
* In the room the unit is in operation
Control Specification
2/3MXL(H) 4MXL(H)
450 480
64 60
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