Daikin RTSQ20PY1 Service Manual

Also see for RTSQ10PY1: Installation manual Service manual

Contents

SiBE31-801_C Refrigerant CircuitRefrigerant Circuit 561.2 RTSQ10PY1, 12PY1No. inrefrigerantsystemdiagramSymbol Name Major Function1 M1C Inverter compressor Inverter compressor is operated on frequencies between 52Hz and 280(266 forRTSQ12P)Hz by using the inverter, while Standard compressor is operated withcommercial power supply only. The number of operating steps is as follows whenInverter compressor is operated in combination with Standard compressor.Compressor operation steps : Refer to P.92~93.2 M2C Standard compressor 1(STD1)3 M1F Inverter fan Because the system is an air heat exchange type, the fan is operated at 9-step rotationspeed by using the inverter.4 Y1E Electronic expansion valve(Main: EVM)While the outdoor heat exchanger is evaporator, PI control is applied to keep the outletsuperheated degree of air heat exchanger constant.5 Y2E Electronic expansion valve(Refrigerant charge: EVJ) Used to open/close refrigerant charge port.6 Y3E Electronic expansion valve(Subcooling: EVT)PI control is applied to keep the outlet superheated degree of subcooling heatexchanger constant.7 Y1SSolenoid valve (Refrigerantregulator gas purging pipeSVG)Used to collect refrigerant to the refrigerant regulator.8 Y2S Four way valve (Dual pressuregas pipe switch: 20SB) Used to switch dual pressure gas pipe to high pressure or low pressure.9 Y3S Four way valve (Heatexchanger switch: 20SA) Used to switch outdoor heat exchanger to evaporator or condenser.10 Y4S Solenoid valve (Refrigerantregulator liquid pipe: SVL) Used to collect refrigerant to the refrigerant regulator.11 Y5S Solenoid valve (Hot gas: SVP) Used to prevent the low pressure from transient falling.12 Y6S Solenoid valve (Main bypass: SVE) This opens in cooling operation.13 Y7S Solenoid valve (Refrigerantregulator discharge pipe: SVO) This is used to discharge refrigerant from the refrigerant regulator.14 Y8S Solenoid valve (Discharge pipeof refrigerant regulator: SVT) Bypass the high pressure gas to the refrigerant regulator.15 S1NPH High pressure sensor Used to detect high pressure.16 S2NPL Low pressure sensor Used to detect low pressure.17 S1PH High pressure switch (ForINV. compressor) This functions when pressure increases to stop operation and avoid high pressureincrease in the fault operation.18 S2PH High pressure switch (ForSTD compressor 1)19 — Pressure regulating valve(Liquid pipe)This is used when pressure increases, to prevent any damage on components causedby pressure increase in transport or storage.20 — Pressure regulating valve(Refrigerant regulator)This is used when pressure increases, to prevent any damage on components causedby pressure increase in transport or storage.21 — Subcooling heat exchanger Apply subcooling to liquid refrigerant.22 — Refrigerant regulator Surplus refrigerant is held according to the operation conditions.23 — Capillary tube Used to return the refrigerating oil separated through the oil separator to the INVcompressor.24 — Capillary tube Used to return the refrigerating oil separated through the oil separator to the STD1compressor.25 — Capillary tube Used to discharge refrigerant from the refrigerant regulator.26 R1T Thermistor (Outdoor air: Ta) Used to detect outdoor temperature, correct discharge pipe temperature, and others.27 R2T Thermistor (Heat exchangergas pipe: Tg)This detects temperature of gas pipe for air heat exchanger. Used to exercise theconstant control of superheated degree when an evaporator is used for outdoor unitheat exchanging.28 R31T Thermistor (INV. dischargepipe: Tdi) Used to detect discharge pipe temperature. Used for compressor temperatureprotection control.29 R32T Thermistor (STD1 dischargepipe: Tds1)30 R4T Thermistor (Heat exchangerdeicer: Tb) Used to detect liquid pipe temperature of air heat exchanger. Used to makejudgements on defrosting operation.31 R5T Thermistor (Subcooling heatexchanger gas pipe: Tsh)Used to detect gas pipe temperature on the evaporation side of subcooling heatexchanger. Used to exercise the constant control of superheated degree at the outletof subcooling heat exchanger.32 R6T Thermistor (Subcooling heatexchanger liquid pipe: Tl)This detects temperature of liquid pipe between the main expansion valve andsubcooling heat exchanger.33 R7T Thermistor (Heat exchangerliquid pipe: Tf)This detects temperature of liquid pipe between the air heat exchanger and mainelectronic expansion valve. Used to make judgements on the recover or dischargerefrigerants to the refrigerant regulator.34 R8T Thermistor (Suction pipe: TsA) Used to detect suction pipe temperature.35 R9T Thermistor (Liquid pipe: Tsc) This detects temperature of liquid pipe between the liquid stop valve and subcoolingheat exchanger.