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Control Specification
Si12-619A
110
Function and Control
3.12.1 Fully Closing with Power ON
Initialize the electronic expansion valve when turning on the power, set the opening position and
develop pressure equalizing.
3.12.2
Pressure
Equalization Control
When the compressor is stopped, open and close the electronic expansion valve and develop
pressure equalization.
3.12.3
Opening
Limit
Outline
Limit a maximum and minimum opening of the electronic expansion valve in the operating room.
Detail
A maximum electronic expansion valve opening in the operating room: 450 pulses
A minimum electronic expansion valve opening in the operating room: 75 pulses
The electronic expansion valve is fully closed in the room where cooling is stopped and is
opened with fixed opening during defrosting.
3.12.4
Gas
Pipe Isothermal Control During Cooling
When the units are operating in multiple rooms, detect the gas piping temperature and correct
the electronic expansion valve opening so that the temperature of the gas pipe in each room
becomes identical.
When the gas pipe temperature > the average gas pipe temperature,
→
open the electronic expansion valve in that room
When the gas pipe temperature < the average gas pipe temperature,
→
close the electronic expansion valve in that room
The temperatures are monitored every 40 seconds.
3.12.5
SC Control
Outline
Heat Pump Only
Detect the temperature of liquid pipe and heat exchanger of the rooms and compensate the
electronic expansion valve opening so that the SC of each room becomes the target SC.
When the actual SC is > target SC, open the electronic expansion valve of the room.
When the actual SC is < target SC, close the electronic expansion valve of the room.
Detail
Start Functioning Conditions
After finishing the open control (630 seconds after the beginning of the operation), control all the
electronic expansion valve in the operating room.
Determine Electronic Expansion Valve Opening
Adjust the electronic expansion valve so that the temperature difference between the maximum
heat exchanger temperature of connected room and the temperature of liquid pipe thermistor
becomes constant.
3.12.6 Starting Operation Control / Changing Operation Room
Control the electronic expansion valve opening when the system is starting or the operating
room is changed, and prevent the system to be super heated or moistened.
Summary of Contents for 3MKS50DVM
Page 13: ...Introduction Si12 619A xii ...
Page 131: ...Control Specification Si12 619A 118 Function and Control ...
Page 213: ...Instruction Si12 619A 200 Operation Manual ...
Page 283: ...Check Si12 619A 270 Service Diagnosis ...
Page 302: ...Si12 619A Outdoor Unit E Series 50 52 58 Class Removal Procedure 289 Step Procedure Points ...
Page 385: ...Wiring Diagrams Si12 619A 372 Appendix FTK X S50 60 71FVLT ...
Page 399: ...Si12 619A vi Index ...