Refrigerant Circuit
SiUS181305E
31
Refrigerant Circuit
1. Refrigerant Circuit
1.1
Outdoor Unit
No. in
diagram
Symbol
Name
Major Function
A
M1C
Compressor motor
The compressor is operated on frequencies between 36 Hz and 195 Hz by using the
inverter. (31 steps)
D
M1F
M2F
Fan motor
Since the system is of air heat exchanging type, the fan is operated at 8-step rotation
speed by using the inverter.
E
Y1E
Electronic expansion valve
(Main)
While in heating operation, PI control is applied to keep the outlet superheated degree of
the air heat exchanger constant.
F
Y3E
Electronic expansion valve
(Subcooling)
PI control is applied to keep the outlet superheated degree of the subcooling heat
exchanger constant.
G
Y2S
Solenoid valve
(Hot gas bypass)
Prevents the low pressure from temporary falling.
H
Y3S
Solenoid valve (Unload circuit) Unloading operation of the compressor.
M
Y1S
Four-way valve
Switches the operation mode between cooling and heating.
N
S1NPH High pressure sensor
Detects high pressure.
O
S1NPL
Low pressure sensor
Detects low pressure.
P
S1PH
High pressure switch
In order to prevent the increase of high pressure when an error occurs, this switch is activated
at high pressure of 4.0 MPa (1338 ftAq) or more to stop the compressor operation.
S
—
Fusible plug
In order to prevent the increase of pressure when abnormal heating is caused by fire, etc., the fusible part
of the plug melts at a temperature of 70 ~ 75°C (158 ~ 167°F) to release the pressure into the atmosphere.
T
—
Pressure regulating valve
(Receiver to discharge pipe)
This valve opens at a pressure of 4.0 MPa (1338 ftAq) to prevent pressure increase, thus protecting
functional parts from damage due to the increase of pressure in transportation or storage.
1
R1T
Thermistor
(Outdoor temperature: Ta)
Detects outdoor temperature, correct discharge pipe temperature, etc.
2
R2T
Thermistor
(Discharge pipe: Tdi)
Detects discharge pipe temperature, for temperature protection control of the compressor,
etc.
3
R3T
Thermistor
(Suction pipe 1: Ts1)
Detects suction pipe temperature, keep the suction superheated degree constant in
heating operation, etc.
4
R4T
Thermistor
(Outdoor heat exchanger: Tb)
Detects liquid pipe temperature of the outdoor heat exchanger, determine defrosting
operation, etc.
5
R5T
Thermistor
(Suction pipe 2: Ts2)
Calculates the internal temperature of the compressor etc.
6
R6T
Thermistor (Subcooling heat
exchanger gas pipe: Tsh)
Controls the subcooling electronic expansion valve.
7
R7T
Thermistor (Liquid pipe: Tl)
Detects refrigerant overcharge in check operation, etc.
Electronic
expansion
v
al
v
e
Do
ub
le pipe
heat exchanger
Electronic
expansion
v
al
v
e
F
u
si
b
le
pl
u
g
Filter
Heat exchanger
Ser
v
ice port
Fo
u
r-
w
ay
v
al
v
e
High press
u
re
sensor
Solenoid
v
al
v
e
Solenoid
v
al
v
e
Lo
w
press
u
re
sensor
Ser
v
ice port
Capillary
t
ub
e
Capillary
t
ub
e
Capillary
t
ub
e
Stop
v
al
v
e (
w
ith ser
v
ice port on field piping side
φ
7.9 mm (
φ
5/16 inch) flare connection)
Compressor
High press
u
re
s
w
itch
Press
u
re
reg
u
lating
v
al
v
e
Filter
Filter
Filter
er
Oil separator
S1
N
PL
S1PH
S1
N
PH
Acc
u
m
u
lator
(F)
(T)
(E)
(D) (D)
(M)
(
N
)
(G)
(P)
(H)
(O)
(A)
(S)
(7)
(6)
(3)
(2)
(5)
(4)
(1)
Содержание RMXS-L Series
Страница 10: ...Safety Considerations Safety Considerations ix...
Страница 11: ...SiUS181305E 1 List of Functions Part 1 List of Functions 1 Functions 2 1 1 Outdoor Unit 2 1 2 Indoor Unit 3...
Страница 129: ...SiUS181305E Field Settings Test Operation and Field Settings 120...
Страница 144: ...FFQ09 12 15 18LVJU SiUS181305E 135 Remote Controller...
Страница 249: ...SiUS181305E Removal Procedure Booklet No Appendix 240...
