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Refrigerant Circuit
ESiEN09-06 A
12
Refrigerant Circuit
1. Refrigerant Circuit
1.1
ERQ 125 A7W1B
No. in
refrigerant
system
diagram
Symbol
Name
Major Function
A
M1C
Inverter compressor (INV)
Inverter compressor is operated on frequencies between 52Hz and 188Hz by using
the inverter. The number of operating steps is as follows when Inverter compressor is
operated.
RXYQ5P: 18 steps
D
M1F
Inverter fan
Since the system is of air heat exchanging type, the fan is operated at 9-step rotation
speed by using the inverter.
E
Y1E
Electronic expansion valve
(Main: EV1)
While in heating operation, PI control is applied to keep the outlet superheated degree
of air heat exchanger constant.
G
Y1S
Solenoid valve (Hot gas: SVP) Used to prevent the low pressure from transient falling.
J
Y2S
Solenoid valve (Oil return: SVO) Used to return oil from the accumulator to the compressor.
K
Y4S
Solenoid valve (Injection) SVT Used to cool the compressor by injecting refrigerant when the compressor discharge
temperature is high.
M
Y3S
4-way valve
Used to switch the operation mode between cooling and heating.
N
S1NPH High pressure sensor
Used to detect high pressure.
O
S1NPL Low pressure sensor
Used to detect low pressure.
P
S1PH
HP pressure switch (For INV
compressor)
In order to prevent the increase of high pressure when a malfunction occurs, this
switch is activated at high pressure of 4.0 MPa or more to stop the compressor
operation.
T
—
Pressure regulating valve 1
This valve opens at a pressure of 4.0 MPa for prevention of pressure increase, thus
resulting in no damage of functional parts due to the increase of pressure in
transportation or storage.
W
—
Capillary tube
Used to return the refrigerating oil separated through the oil separator to the
compressor.
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.
3
R3T
Thermistor (INV discharge
pipe: Tdi)
Used to detect discharge pipe temperature, make the temperature protection control of
compressor, and others.
4
R4T
Thermistor (Heat exchanger
deicer: Tb)
Used to detect liquid pipe temperature of air heat exchanger, determine defrosting
operation, and others.
5
R6T
Thermistor (Liquid pipe Tl)
Used to detect liquid pipe temperature.
6
R7T
Thermistor (Accumulator inlet
Ts1)
Used to detect gas pipe temperature at the accumulator inlet. Keep the suction
superheated degree constant in heating operation, and others.
Summary of Contents for ERQ Series
Page 2: ......
Page 16: ...Combination Table ESiEN09 06 A 6 General Information...
Page 17: ...ESiEN09 06 A Specifications 7 1 Specifications 8 1 1 Outdoor Units 8...
Page 33: ...ESiEN09 06 A Function general Function 23 1 2 Operation Mode...
Page 58: ...Outline of Control ESiEN09 06 A 48 Function...
Page 71: ...ESiEN09 06 A Wiring Diagram of Control Box Control Box EKEQ CBV3 61 3 2 F box...
Page 109: ...Test Operation ESiEN09 06 A 100 Test Operation 1 2 2 Turn power on...