Daikin VRV III REYQ8PY1, Service Manual

Page: 106 / 452

Si37-701
Function 95
Part 4
Function
1. Function General...................................................................................96
1.1 Symbol ...................................................................................................96
1.2 Operation Mode......................................................................................98
2. Basic Control.........................................................................................99
2.1 Normal Operation ...................................................................................99
2.2 Compressor PI Control.........................................................................100
2.3 Electronic Expansion Valve PI Control.................................................108
2.4 Step Control of Outdoor Unit Fans .......................................................108
2.5 Outdoor Unit Fan Control in Cooling Operation ...................................109
2.6 Heat Exchanger Control .......................................................................110
3. Special Control....................................................................................111
3.1 Startup Control .....................................................................................111
3.2 Large Capacity Start Up Control (Heating)...........................................113
3.3 Oil Return Operation ............................................................................114
3.4 Defrost Operation .................................................................................118
3.5 Pump-down Residual Operation ..........................................................120
3.6 Standby ................................................................................................122
3.7 Stopping Operation ..............................................................................123
4. Protection Control ...............................................................................124
4.1 High Pressure Protection Control.........................................................124
4.2 Low Pressure Protection Control..........................................................126
4.3 Discharge Pipe Protection Control .......................................................128
4.4 Inverter Protection Control ...................................................................129
4.5 STD Compressor Overload Protection.................................................131
5. Other Control.......................................................................................132
5.1 Backup Operation.................................................................................132
5.2 Demand Operation ...............................................................................132
5.3 Heating Operation Prohibition ..............................................................132
6. Outline of Control (Indoor Unit) ...........................................................133
6.1 Operation Flow Chart ...........................................................................133
6.2 Thermostat Control...............................................................................135
6.3 Drain Pump Control..............................................................................139
6.4 Control of Electronic Expansion Valve .................................................141
6.5 Freeze Prevention ................................................................................142
6.6 Heater Control (Optional PC Board KRP1B...is required.) ...................143
6.7 List of Swing Flap Operations ..............................................................144
6.8 Hot Start Control (In Heating Operation Only)......................................145
6.9 Louver Control for Preventing Ceiling Dirt............................................146