Daikin R410As Service Manual

Contents

Daikin R410As Service Manual Manual pdf 55 page image

Refrigerant Circuit Si39-30244 Refirgerant Circuit1.2 RXYQ8, 10, 12MNo. inrefrigerantsystemdiagramSymbol Name Major FunctionA M1C Inverter compressor (INV) Inverter compressor is operated on frequencies between 52 Hz and 210 Hz by usingthe inverter, while Standard compressor is operated with commercial power supplyonly. The number of operating steps is as follows when Inverter compressor isoperated in combination with Standard compressor.RXYQ8, 10, 12M: 29 stepsB M2C Standard compressor 1(STD1)D M1F Inverter fan Since the system is of air heat exchanging type, the fan is operated at 8-step rotationspeed by using the inverter.E Y1E Electronic expansion valve(Main: EV1) While in heating operation, PI control is applied to keep the outlet superheated degreeof air heat exchanger constant.F Y2E Electronic expansion valve(Subcool: EV2) PI control is applied to keep the outlet superheated degree of subcooling heatexchanger constant.G Y1S Solenoid valve (Hot gas: SVP) Used to prevent the low pressure from transient falling.H Y2S Solenoid valve (Oilequalization: SVO) Used for oil equalizing among outdoor units in multiple-outdoor-unit system.I Y3S Solenoid valve (Receiver gascharging: SVL)Used to maintain high pressure while in cooling operation at low outdoor temperature.And also used to prevent the accumulation of refrigerant in non-operating outdoorunits in the case of multiple-outdoor-unit system.J Y4S Solenoid valve (Receiver gasdischarging: SV) Used to collect refrigerant to receiver.K Y5S Solenoid valve (Non-operatingunit gas discharging SVSG) Used to prevent the accumulation of refrigerant in non-operating outdoor units in thecase of multiple-outdoor-unit system.L Y6S Solenoid valve Non-operatingunit liquid pipe closing: SVSL)Used to prevent the accumulation of refrigerant in non-operating outdoor units in thecase of multi-outdoor unit system.M Y7S 4-way valve Used to switch the operation mode between cooling and heating.NS1NPH High pressure sensor Used to detect high pressure.O S1NPL Low pressure sensor Used to detect low pressure.P S1PH HP pressure switch (For INVcompressor) In order to prevent the increase of high pressure when a malfunction occurs, thisswitch is activated at high pressure of 3.8 MPA or more to stop the compressoroperation.Q S2PH HP pressure switch (For STDcompressor 2)S — Fusible plugIn order to prevent the increase of pressure when abnormal heating is caused by fireor others, the fusible part of the plug is molten at a temperature of 70 to 75°C torelease the pressure into the atmosphere.T — Pressure regulating valve 1(Receiver to discharge pipe)This valve opens at a pressure of 2 to 2.7 MPa for prevention of pressure increase,thus resulting in no damage of functional parts due to the increase of pressure intransportation or storage.U — Pressure regulating valve 2(Liquid pipe to receiver)V — Pressure regulating valve 3(Equalizing pipe to dischargepipe)1 R1T Thermistor (Outdoor air: Ta) Used to detect outdoor temperature, correct discharge pipe temperature, and others.2 R2T Thermistor (Suction pipe: Ts) used to detect suction pipe temperature, keep the suction superheated degreeconstant in heating operation, and others.3 R31T Thermistor (INV dischargepipe: Tdi)used to detect discharge pipe temperature, make the temperature protection control ofcompressor, and others.4 R32T Thermistor (STD1 dischargepipe: Tds1)5 R33T Thermistor (STD2 dischargepipe: Tds2)6 R4T Thermistor (Heat exchangerdeicer: Tb) Used to detect liquid pipe temperature of air heat exchanger, determine defrostingoperation, and others.7 R5T Thermistor (Subcooling heatexchanger gas pipe: Tsh)Used to detect gas pipe temperature on the evaporation side of subcooling heatexchanger, keep the superheated degree at the outlet of subcooling heat exchangerconstant, and others.8 R6T Thermistor (Receiver outletliquid pipe: Tl)Used to detect receiver outlet liquid pipe temperature, prevent the drift betweenoutdoor units while in heating operation in the case of multiple-outdoor-unit system,and others.9 R7T Thermistor (Oil equalizingpipe: To) Used to detect equalizing pipe temperature, opening/closing of the equalizing pipestop valve, and others.