Control Specification
SiUS12-928_B
65
Function and Control
3.12.1 Fully Closing with Power on
The outdoor electronic expansion valve is initialized when the power is turned on. The opening
position is set and the pressure equalization is developed.
3.12.2 Pressure Equalizing Control
When the compressor is stopped, the pressure equalizing control is activated. The outdoor
electronic expansion valve opens, and develops the pressure equalization.
3.12.3 Opening Limit Control
Outline
The maximum and minimum opening of the outdoor electronic expansion valve are determined.
Detail
Maximum outdoor electronic expansion valve opening in the operating room: 450 pulses
Minimum outdoor electronic expansion valve opening in the operating room: 75 pulses
The outdoor electronic expansion valve is fully closed in a room where cooling operation is stopped
and is opened at a fixed degree during defrosting.
3.12.4 Starting Operation Control / Changing Operation Room
The outdoor electronic expansion valve opening is controlled when the operation starts, and
prevents superheating or liquid compression.
3.12.5 Control when the Frequency Changes
When the target discharge pipe temperature control is active, if the target frequency is changed to a
specified value in a certain time period, the target discharge pipe temperature control is canceled
and the target opening of the outdoor electronic expansion valve is changed.
3.12.6 Oil Recovery Function
Outline
Outdoor electronic expansion valve opening in a room where cooling operation is stopped is set to
open for a certain time at specified intervals so that the oil does not accumulate.
Detail
During cooling operation, after every 1 hour of continuous operation, the outdoor electronic
expansion valves in the operation stopped room is opened by 80 pulses for specified time.
3.12.7 High Discharge Pipe Temperature Control
When the compressor is operating, if the discharge pipe temperature exceeds a certain value, the
outdoor electronic expansion valve opens and the refrigerant runs to the low pressure side.
This procedure lowers the discharge pipe temperature.
