SiENBE28-901
Standard Specification
Air Cooled Refrigeration Condensing Unit
21
2.6
Description and Layout of Functional Parts and Piping
Diagram
LRMEQ5, 6AY1
LRLEQ5, 6AY1
No.
Name
Symbol
Function
1
Inverter compressor (INV)
M1C
An inverter-driven compressor, which runs at operating frequencies in the
range of 52Hz to 218Hz.
2
Fan motor
M1F
Used to operate a fan for heat exchange through an air heat exchanger.
3
Electronic expansion valve
(Main: EV1)
Y1E
Not used.
4
Electronic expansion valve
(Injection: EV2)
Y2E
Used to control the injection flow rate and the compressor overheat
protection.
5
Four way valve
Y3S
Not used.
6
High pressure sensor
S1NPH
Used to detect high pressure.
7
Low pressure sensor
S1NPL
Used to detect low pressure.
8
High pressure switch
S1PH
In order to prevent the increase of high pressure when a malfunction
occurs, this switch activated at high pressure of 3.8MPa or more to stop the
compressor operation.
9
High pressure switch
S4PH
Not used.
10
Fusible plug
—
When the refrigerant of the receiver unit reaches a temperature of 70°C to
75°C, the fusible head of plug will melt, thus discharging the refrigerant of
high temperature and high pressure.
11
Pressure regulating valve
—
Opens when the pressure reaches 4.0 MPa. This prevents an excessive
pressure rise caused by the pipes being completely filled with liquid when
not in operation.
12
Double pipe heat
exchanger
—
Used to cool the liquid refrigerant from the liquid receiver.
13
Stop valve (Heat
exchanger on primary side)
—
Used to service.
14
Stop valve (Double pipe
heat exchanger on
secondary side)
—
Used to service.
15
Service port
—
For gas (high pressure).
16
Service port
—
For liquid (high pressure).
17
Service port
—
For gas (low pressure).
18
Oil separator
—
Refrigerant gas discharged from the compressor contains lubricating oil in
the compressor. If the amount of this lubricating oil is large, the oil quantity
in the compressor will become short, which may result in defective
lubrication.
Furthermore, this oil stains the heat transfer surface of condenser or
evaporator and reduces the effectiveness of the heat exchanger. To avoid
that, an oil separator is installed in close proximity to the discharge pipe of
the compressor, where oil is separated and collected to return to the
compressor.
19
Liquid receiver
—
Used to compensate the variations in handling of refrigerant, thus providing
stable operating conditions at all times. In order to repair in the refrigerant
circuit, this receiver collects the refrigerant and facilitates the repairing of
the parts.
20
Sight glass
—
Used to test run and service.
A
Thermistor (Outdoor air:
Ta)
R1T
Used to detect the outdoor temperature and control the fan operation.
B
Thermistor (Suction pipe:
Ti)
R2T
Used to detect the suction pipe temperature of M1C compressor and
protect this compressor.
C
Thermistor (INV discharge
pipe: Td1)
R31T
Used to detect the discharge pipe temperature of M1C compressor and
control over discharge pipe temperature of this compressor for protection.
D
Thermistor (Heat
exchanger deicer: Tce)
R3T
Not used.
E
Thermistor (Double pipe
heat exchanger outlet: Tg)
R5T
Used to detect the gas temperature at evaporator side of double pipe heat
exchanger, and keep the constant overheated degree of double pipe heat
exchanger.
F
Thermistor (Double pipe
heat exchanger inlet: TL)
R6T
Used to detect the gas saturation temperature at evaporator side of double
pipe heat exchanger.
