Daikin REYQ-TA Series Service Manual page 27

SiUS371614E
1.1.2 REYQ96-168TAYDU, REYQ96-168TATJU
No. in
Electric
piping
symbol
diagram
(1) M1C Inverter compressor
(2) M2C Inverter compressor
(3) M1F
Inverter fan
(4) M2F
Electronic expansion valve
(5) Y1E
(Heat exchanger upper)
Electronic expansion valve
(6) Y2E
(Subcooling heat exchanger)
Electronic expansion valve
(7) Y3E
(Heat exchanger lower)
Electronic expansion valve
(8) Y4E
(Receiver gas purge)
Electronic expansion valve
(9) Y5E
(Refrigerant cooling)
Electronic expansion valve
(10) Y6E
(Leak detection)
Solenoid valve
(11) Y1S
(OS oil return 1)
Solenoid valve
(12) Y2S
(OS oil return 2)
(13) Y3S Solenoid valve (Liquid shutoff) Used to return oil from the accumulator to the compressor.
(14) Y4S Four way valve (HP/LP gas)
Four way valve
(15) Y5S
(Heat exchanger lower)
Four way valve
(16) Y6S
(Heat exchanger upper)
(17) S1NPH High pressure sensor
(18) S1NPL Low pressure sensor
High pressure switch
(19) S1PH
(For M1C)
High pressure switch
(20) S2PH
(For M2C)
Pressure regulating valve
(21) —
(Liquid pipe)
(22) — Subcooling heat exchanger
(23) — Capillary tube
(24) — Capillary tube
(25) R1T Thermistor (Outdoor air)
(26) R21T Thermistor (M1C discharge)
(27) R22T Thermistor (M2C discharge)
(28) R3T Thermistor (Receiver inlet)
Thermistor (Heat exchanger
(29) R4T
liquid upper)
Thermistor (Heat exchanger
(30) R5T
liquid lower)
(31) R6T Thermistor (Subcooling gas)
(32) R7T Thermistor (Subcooling liquid) This detects temperature of liquid pipe for subcooling heat exchanger.
Thermistor (Heat exchanger
(33) R8T
gas upper)
Thermistor (Heat exchanger
(34) R9T
gas lower)
(35) R10T Thermistor (Suction)
(36) R11T Thermistor (Deicer)
Thermistor (Compressor
(37) R12T
suction)
Thermistor
(38) R13T
(Receiver gas purge)
(39) R14T Thermistor (M2C body)
(40) R15T Thermistor (Leak detection)
Refrigerant Circuit
Name
Inverter compressor is operated on frequencies between 52 Hz to 210 Hz by using the
inverter. Compressor operation steps: Refer to page 66~
Because the system is an air heat exchange type, the fan is operated at 9-step rotation
speed by using the inverter.
While in heating, PI control is applied to keep the outlet superheated degree of air heat
exchanger constant.
PI control is applied to keep the outlet superheated degree of subcooling heat exchanger
constant.
While in heating, PI control is applied to keep the outlet superheated degree of air heat
exchanger constant.
Used to collect the refrigerant to receiver.
Used to control the refrigerant amount to cool the diode bridge and power module of the
inverter PCB.
Used to detect refrigerant leakage.
Used to return oil from the oil separator to the compressor (M1C).
Used to return oil from the oil separator to the compressor (M2C).
Used to switch dual pressure gas pipe to high pressure or low pressure.
Used to switch outdoor heat exchanger to evaporator or condenser.
Used to detect the high pressure.
Used to detect the low pressure.
This functions when pressure increases to stop operation and avoid high pressure
increase in the fault operation.
This is used when pressure increases, to prevent any damage on components caused by
pressure increase in transport or storage.
Apply subcooling to liquid refrigerant.
Used to return the refrigerating oil separated through the oil separator to the M1C
compressor.
Used to return the refrigerating oil separated through the oil separator to the M2C
compressor.
Used to detect outdoor air temperature, correct discharge pipe temperature and others.
Used to detect discharge pipe temperature.
Used to detect liquid pipe temperature of receiver inlet.
This detects temperature of liquid pipe for air heat exchanger.
Used to detect gas pipe temperature on the evaporating side of subcooling heat
exchanger. Used to exercise the constant control of superheated degree at the outlet of
subcooling heat exchanger.
This detects temperature of gas pipe for air heat exchanger.
Used to detect suction pipe temperature.
Used to detect liquid pipe temperature of air heat exchanger. Used to make judgements
on defrost operation.
Used to detect suction pipe temperature of compressor.
Used to detect gas pipe temperature of receiver gas purge piping.
Detects compressor surface temperature, this switch is activated at surface temperature
of 120°C (248°F) or more to stop the compressor. (144/168 class models only)
The thermistor detects refrigerant leakage.
Major function
Refrigerant Circuit
14