Refrigerant Circuit; Reyq72, 96, 120Pydn, Ptju - Daikin RXYQ96PYDN Service Manual

Refrigerant Circuit

2. Refrigerant Circuit

2.1

REYQ72, 96, 120PYDN, PTJU

No. in
refrigerant
Symbol
system
diagram
1 M1C Inverter compressor (INV)
2 M2C Standard compressor 1 (STD1)
3 M1F Inverter fan
4 M2F Inverter fan
Y1E Electronic expansion valve
5(6)
(Y3E) (Main1 (Main2))
Y2E Electronic expansion valve
7(8)
(Y5E) (Subcool1 (Subcool2))
Electronic expansion valve
9 Y4E
(Refrigerant charge EVJ)
Y5S Solenoid valve (Main bypass1
10(11)
(Y10S) (Main bypass2))
12 Y4S Solenoid valve (Hot gas: SVP)
Solenoid valve (Refrigerant
13 Y3S
regulator liquid pipe SVL)
Solenoid valve (Refrigerant
14 Y1S
regulator gas purging pipe SVG)
Solenoid valve (Refrigerant
15 Y7S
regulator discharge pipe SVO)
Solenoid valve (Discharge pipe
16 Y6S
of refrigerant regulator)
Y2S 4-way valve (Heat exchanger
17(18)
(Y9S) switch 20SA)
4-way valve (Dual pressure gas
19 Y8S
pipe switch 20SB)
20 S1NPH High pressure sensor
21 S2NPL Low pressure sensor
22 S1PH HP pressure switch (For INV)
23 S2PH HP pressure switch (For STD)
Pressure regulating valve
24 —
(Liquid pipe)
Pressure regulating valve
25 —
(Refrigerant regulator)
26 — Subcooling heat exchanger
27 — Refrigerant regulator
28 — Capillary tube
29 — Capillary tube
30 — Capillary tube
31 R1T Thermistor (Outdoor air: Ta)
R8T
32(42) Thermistor (Suction pipe: TsA)
(R10T)
Thermistor (INV discharge pipe:
33 R31T
Tdi)
Thermistor (STD1 discharge
34 R32T
pipe: Tds1)
R4T Thermistor (Heat exchanger
35(45)
(R12T) deicer: Tb)
R2T Thermistor (Heat exchanger gas
36(46)
(R11T) pipe Tg)
R7T Thermistor (Heat exchanger
37(47)
(R15T) liquid pipe Tf)
R5T Thermistor (Subcooling heat
38(48)
(R13T) exchanger gas pipe: Tsh)
Thermistor (Subcooling heat
39 R6T
exchanger liquid pipe Tl)
R9T
40(50) Thermistor (Liquid pipe Tsc)
(R14T)
128
Name
Inverter compressor is operated on frequencies between 52Hz and 210Hz by using the
inverter, while Standard compressor is operated with commercial power supply only. The
number of operating steps is as follows when Inverter compressor is operated in
combination with Standard compressor: REYQ8, 10, 12P : 37 steps
Since the system is of
the inverter.
Since the system is of
the inverter.
While in heating operation, PI control is applied to keep the outlet superheated degree of
outdoor unit heat exchanger constant.
PI control is applied to keep the outlet superheated degree of subcooling heat exchanger
constant.
Used to open/close refrigerant charge port.
Opens in cooling operation.
Used to prevent the low pressure from reducing.
Used to collect refrigerant to the refrigerant regulator.
Used to collect refrigerant to the refrigerant regulator.
Used to discharge refrigerant from the refrigerant regulator.
Bypasses the high pressure gas to the refrigerant regulator.
Used to switch outdoor heat exchanger to evaporator or condenser.
Used to switch dual pressure gas pipe to high pressure or low pressure.
Detects high pressure.
Detects low pressure.
Functions when pressure increases to stop operation and avoid high pressure increase in
the event of a fault.
Used when pressure increases, to prevent any damage on components caused by pressure
increase in transport or storage.
Used when pressure increases, to prevent any damage on components caused by pressure
increase in transport or storage.
Apply subcooling to liquid refrigerant.
Surplus refrigerant is held according to the operation conditions.
Returns the refrigerating oil separated through the oil separator to the INV compressor.
Returns the refrigerating oil separated through the oil separator to the STD1 compressor.
Discharges refrigerant from the refrigerant regulator.
Detects outdoor temperature, correct discharge pipe temperature, and others.
Detects suction pipe temperature.
Detects discharge pipe temperature. Used for compressor temperature protection control.
Detects liquid pipe temperature of
on defrosting operation.
Detects temperature of gas pipe for
control of superheated degree when an evaporator is used for outdoor unit heat exchanging.
Detects temperature of liquid pipe between the
expansion valve. Used to make judgments on the recover or discharge refrigerants to the refrigerant
regulator.
Detects gas pipe temperature on the evaporation side of subcooling heat exchanger. Used to exercise
the constant control of superheated degree at the outlet of
Detects temperature of liquid pipe between the main expansion valve and subcooling heat
exchanger.
Detects temperature of liquid pipe between the liquid stop valve and subcooling heat
exchanger.
Major Function
the outdoor unit
heat exchanging type, the fan is operated at 9-step rotation speed by using
the outdoor unit
heat exchanging type, the fan is operated at 9-step rotation speed by using
the outdoor unit
heat exchanger. Used to make judgments
the outdoor unit
heat exchanger. Used to exercise the constant
the outdoor unit
VRVIII R-410A Heat Recovery 60Hz
SiUS34-801A_b
heat exchanger and main electronic
heat exchanger.
subcooled