Daikin REYQ8-48PY1B, Service Manual

Page: 114 / 477

SiBE37-701_B
103 Function
Part 4
Function
1. Function General.................................................................................104
1.1 Symbol .................................................................................................104
1.2 Operation Mode....................................................................................106
2. Basic Control.......................................................................................107
2.1 Normal Operation .................................................................................107
2.2 Compressor PI Control.........................................................................108
2.3 Electronic Expansion Valve PI Control.................................................116
2.4 Step Control of Outdoor Unit Fans .......................................................116
2.5 Outdoor Unit Fan Control in Cooling Operation ...................................117
2.6 Heat Exchanger Control .......................................................................118
3. Special Control....................................................................................119
3.1 Startup Control .....................................................................................119
3.2 Large Capacity Start Up Control (Heating)...........................................121
3.3 Oil Return Operation ............................................................................122
3.4 Defrost Operation .................................................................................126
3.5 Pump down Residual Operation...........................................................128
3.6 Standby ................................................................................................130
3.7 Stopping Operation ..............................................................................131
4. Protection Control ...............................................................................132
4.1 High Pressure Protection Control.........................................................132
4.2 Low Pressure Protection Control..........................................................134
4.3 Discharge Pipe Protection Control .......................................................136
4.4 Inverter Protection Control ...................................................................137
4.5 STD Compressor Overload Protection.................................................139
5. Other Control.......................................................................................140
5.1 Backup Operation.................................................................................140
5.2 Demand Operation ...............................................................................140
5.3 Heating Operation Prohibition ..............................................................140
6. Outline of Control (Indoor Unit) ...........................................................141
6.1 Operation Flow Chart ...........................................................................141
6.2 Thermostat Control...............................................................................143
6.3 Drain Pump Control..............................................................................147
6.4 Control of Electronic Expansion Valve .................................................149
6.5 Freeze Prevention ................................................................................150
6.6 Heater Control (Optional PCB KRP1B...is required.) ...........................151
6.7 List of Swing Flap Operations ..............................................................152
6.8 Hot Start Control (In Heating Operation Only)......................................153
6.9 Louver Control for Preventing Ceiling Dirt............................................154