Huawei NetCol8000-A Series User manual

Copyright © Huawei Technologies Co., Ltd. 2019 All rights reserved.
1Product Overview
Item
Product Model Dimensions Without Packing
(H x W x D) (mm)
Optional
Component
Indoor
unit
NetCol8000
-A045D
2000 x 900 x 900
Electric heater and wet
film humidifier, differential
pressure sensor, water
leakage sensor,
temperature and humidity
sensor
NetCol8000
-A045U
2000 x 900 x 900
NetCol8000
-A090D
2000 x 1800 x 1000
Outdoor
unit
NetCol500
-A060
(
52273539,
52273539
-002)
D =
1094, W1 = 1356, W2 = 1217, H1 =
1107, H2
= 677
Low
-temperature
component
NetCol500
-A060
(
52273539-005,
52273539
-006)
Category B: D = 1094,
W1 = 1356,
W2 =
1217
, H1 = 1107, H2 = 655
Category C: D = 1094,
W1 = 1356,
W2 =
1217
, H1 = 1156, H2 = 725
NetCol500
-A080
(
52273541,
52273541
-002)
D = 1094,
W1 = 2186, W2 = 2047, H1 =
1107, H2 = 677
NetCol500
-A080
(
52273541-005)
D = 1094,
W1 = 2186, W2 = 2047, H1 =
1107, H2 = 655
NetCol500
-A120
(
52273755-002)
D = 2189,
W1 = 1356, W2 = 1217, H1 =
1107, H2 = 655
NetCol8000
-A045 is a single-system unit. NetCol8000-A090 is a dual-system unit.
NetCol500
-A060 and NetCol500-A080 are single-system units. NetCol500-A120 is a dual-
system unit.
A single
-system indoor unit is used with a single-system outdoor unit; two single-system indoor units
are used together with a dual
-system outdoor unit; a dual-system indoor unit is used with two single-
system outdoor units; a dual
-system indoor unit is used with a dual-system outdoor unit.
1
Issue: 01
Part Number: 31500BLY
Date: 2019-09-30
NetCol8000-A (045,090) In-room Air
Cooled Smart Cooling Product
Quick Guide

2
Mandatory
items
Refrigerant
pipe
0 m < L ≤ 60 m:
Gas pipe:
outer diameter of 7/8 inch (22.22 mm) ; wall thickness of 1.2
mm; operating pressure > 4.5 MPa
Liquid
pipe:
outer diameter of 5/8 inch (15.88 mm) ; wall thickness of 1.0
mm; operating pressure > 4.5 MPa
60 m < L ≤ 100 m
:
Gas pipe:
outer diameter of 1 inch (25.4 mm) ; wall thickness of
1.2 mm;
operating pressure > 4.5 MPa
Liquid
pipe: outer diameter of 3/4 inch (19.05 mm) ; wall thickness of
1.0
mm; operating pressure > 4.5 MPa
Thermal insulation foam
, thickness ≥9.2mm
Oil traps and inverted traps , Pipe supports
Mandatory
items
(Optional)
Humidifier
water inlet pipe

Connecting rigid pipe: G 3/4-inch inner screw thread to rigid pipe
connector, rigid pipe (made of PP-R or other materials)

Connecting hose: G 3/4-
inch inner screw thread to pagoda connector,
hose (made of EPDM or other materials)
Drainpipe

Connecting rigid pipe: G 3/4-inch outer screw thread to rigid pipe
connector, rigid pipe (made of PP-R or other materials)

Connecting hose: G 3/4-
inch outer screw thread to pagoda connector,
hose (made of EPDM or other materials)
Thermal insulation foam
Cables
•
Power cable of NetCol8000-A045 indoor unit: 5 x 10 mm²
(L1/L2/L3/N/PE)
•
Power cable of NetCol8000-A090 indoor unit: 4 x 25 mm²
(L1/L2/L3/N) + 16 mm²(PE)
•
Power cable of outdoor unit: 5 x 2.5 mm²
•
Signal cable of outdoor unit and indoor unit: 3 x 1.5 mm²(
for outdoor
units 52273539, 52273539-002, 52273541, and 52273541-002 only
)
Base
Base
of indoor unit (recommended for downflow unit) , outdoor unit
support
or concrete base (determined based on scenarios)
Optional
items
Low
-
temperature
component
cable
If low
-temperature component is configured, an additional 2 x 1.5 mm²
power cable is needed.
Teamwork
networking and
monitoring
cable
If teamwork networking
is required, prepare a standard 8pin RJ45
network cable for each device.
If monitoring is required, prepare one 2pin network cable for each device.
Refrigerant R410A
2.1
Do not use unqualified refrigerant. Huawei will not be liable for any equipment damage caused by
unqualified refrigerant.
You can verify the refrigerant authenticity in the following ways:
1. Dial the refrigerant manufacturer's hotline to confirm the refrigerant manufacturer authenticity.
2. Place the refrigerant tank indoors for 24 hours. Use a point thermometer to measure the outer
surface temperature of the refrigerant tank (figure 1) , and connect a pressure gauge to the
tank to measure the internal pressure (figure 2). Find the saturation pressure corresponding to
the measured outer surface temperature from the table on the next page. If the deviation
between the saturation pressure and the measured internal pressure is greater than 0.2 MPa,
the refrigerant does not meet the requirements, and needs to be replaced.
2Engineering Materials

Mapping Between Saturation Temperatures and Pressure of R410A
Saturation
temperature (
ºC )
Gauge
(MPa)
Saturation
temperature (
ºC
)
Gauge
(MPa)
Saturation
temperature (
ºC )
Gauge (MPa)
10
0.99
19
1.31
28
1.69
11
1.02
20
1.35
29
1.74
12
1.05
21
1.39
30
1.79
13
1.09
22
1.43
31
1.84
14
1.12
23
1.47
32
1.89
15
1.16
24
1.51
33
1.94
16
1.19
25
1.56
34
1.99
17
1.23
26
1.60
35
2.05
18
1.27
27
1.65
36
2.10
7/8 inch Oil trap
7/8 inch Gas pipe
inverted trap 3/4 inch Liquid pipe inverted trap
Oil Trap and Inverted Trap
2.2
Unit: mm
5/8 inch Liquid
pipe inverted trap
1 inch Oil trap
1 inch Gas pipe
inverted trap
3

Liquid pipe
needle valve
Exhaust pipe
needle valve
Low-pressure
needle valve
4
Checking Whether the Nitrogen Is Discharged at the Needle Valves
3.1
Removing the Pallet
3.2
Liquid pipe
needle valve
Exhaust pipe
needle valve
Low-pressure
needle valve
Upflow
Downflow
Outdoor unit
1. Read the related user manual or instructions before installing the NetCol8000-A.
2. The unit in this document is a fully configured NetCol8000-A. If some components are not
configured, skip the corresponding steps.
3. You are recommended to use tools that are fully insulated when installing devices.
4. Only engineers from the manufacturer or engineers certified by the agent are allowed to install,
commission, and maintain smart cooling product. Otherwise, personal injuries and device
damage may be caused, which is beyond the smart cooling product warranty range.
3Installing the Indoor Unit

Securing to the Floor or Base
3.4
Removing Compressor Fasteners
3.3
1. Remove the six screws and
then the beam. 2. Rotate the fan upward by 30 degrees, and pull the rotating
shaft of the fan to the
outermost side.
3. Slowly rotate the fan by 90
degrees and ensure that the
rotating shaft of the fan is on
the outermost side. Exercise
caution when handling the fan
to avoid body injury.
4. After the fan rotates to the position
shown in the figure, push the fan
back to the horizontal position.
5. Secure the beam and tighten
the six screws on the fan
support.
Lowering a Fan (Applicable to Downflow Units)
3.5
4Installing the Outdoor Unit
•Protective cardboard for fins must be removed after installation to protect people from injuries.
•The installation methods of installing NetCol500-A060, NetCol500-A080 and NetCol500-A120
outdoor units are the same. This section describes how to install a NetCol500-A060.
•If the space does not meet the requirements of the recommended layout, you can use any of the
layouts (applicable only to NetCol500-A060) in user manual.
5

Unit: mm
Scenario 1: Horizontal Installation Scenario 2: Vertical Installation
6
Installation Scenario
4.1
Make sure that no shelter is above the outdoor unit.
NOTE
b. Install the four legs.
a. Remove the straight flanges.
Horizontal installation (Choose One from the Two Installation Scenario)
4.2
c. Secure the legs to the concrete base.

7
Vertical Installation (Choose One from the Two Installation Scenario)
4.3
5Welding Refrigerant Pipes
1. When outdoor unit is installed horizontally, the outdoor unit and the low-temperature component
must be at the same horizontal plane. When outdoor unit is installed vertically, the installing
horizontal plane of outdoor unit must not be lower than the installing horizontal plane of low-
temperature component, and the height difference cannot exceed 1.5 m.
2. When calculating the height difference, the compressor base is regarded as the baseline for the
indoor unit, and the condenser top is regarded as the baseline for the outdoor unit.
3. The inverted trap should be higher than the top copper pipe of the condenser.
4. When the indoor unit is higher than the outdoor unit, the maximum height difference is 8 m. When
the indoor unit is lower than the outdoor unit, the maximum height difference is 30 m.
5. When welding pipes, ensure that the pipes are dry. You are recommended to weld the pipes
between the indoor and outdoor units, then connect the two ends of the pipe to the indoor unit and
outdoor unit.
6. Use a rubber hose to connect the nitrogen cylinder which connecting the reducing valve and the
end of the copper pipe, then fill nitrogen at 0.03–0.05 MPa into the copper pipe to avoid internal
oxidation.
7. After the pipe in the middle is welded, charge nitrogen into the pipe from one pipe end to clear the
foreign matter inside.
8. Do not expose welding positions to the environment for a long time. Take sealing measures for
welding positions. If foreign matter exists at the welding position, rubber it out using non-water
alcohol or damp cloth before the welding.
9. Take protective measures, such as spreading a piece of wet cloth, around the welding position, to
avoid burning the bottom panel, top panel, side panel, internal components, needle valves, other
pipes, thermal insulation foam, power cables, labels, and tags.
Wall
Pipe
Pipe support
Laying the Engineering Pipe
5.1

Discharging Nitrogen of Indoor Unit
5.2
UpflowDownflow
8
Downflow-Bottom Piping
Welding the Indoor Unit Ports
5.3
Upflow-Bottom Piping
Upflow-Side Piping
Downflow-Side Piping
(1) Gas pipe
(2) Liquid pipe

Exhaust nitrogen from the three needle
valves respectively. Do not remove the
needle valve plug in case of loss or damage.
Welding the Outdoor Unit Ports5.5
9
Thermal
insulation
foam
5/8 inch
liquid pipe
7/8 inch
gas pipe
Discharging Nitrogen at the
Outdoor Unit Needle Valves
5.4
(Optional) Connecting Low Temperature Component Pipes
5.6
To indoor unit
liquid pipe To indoor unit gas pipe
To outdoor unit gas pipe
To outdoor unit liquid pipe
•When the outdoor is installed vertically, the
gas pipe should be connected to the top
port and liquid pipe should be connected to
the bottom port.
•A reducing pipe is required when welding
3/4 inch copper pipe to 5/8 inch connector.
6Connecting Water Pipes
Connecting the Humidifier Water Inlet Pipe
6.1
G 3/4 inch reserved connector
with outer screw thread
G 3/4 inch adapter with inner screw thread1
Matched with the adapter, the pressure
resistance should be at least 0.7 MPa

10
Connecting the Drainpipe
6.2
Connection method
(1) Connector with inner
screw threads
(4) Pagoda connector
(2) Rigid pipe adapter
(5) Hose clamp
(3) Rigid pipe
(6) Hose
The drainpipe from indoor unit to condensate
branch pipe must have gradients (＞1: 100).
Significant upward trend and stagnant water is
not allowed along the pipe.
UpflowDownflow
Note 1:
1. When plastic materials such as PA66 are used, the
recommended torque is 5 N.m.
2. When metal materials are used, the recommended torque is 10
N.m. A sealing washer must be used when an union is used.
7Installing Cables
1. The power cables and signal cables should be tied and cased separately.
2. The shielding layer of signal cable must be grounded.
3. In bottom cabling, if it is hard to bend the cable 90°, disassemble the cable and fix it using the pipe
clamp. As the PE cable is long, prepare the five-core cable based on the length of the PE cable.
4. The following picture shows the duel power supply modes. In single power supply mode, only QF1
needs to be connected.

11
Connecting the Indoor Unit Power Cable
7.1
Downflow
Upflow

1. Outdoor units of different models have
different electric control box layout but the
same port silk screen. Ensure that cable
labels are consistent with corresponding
terminal labels when connecting cables.
2. The following figure shows the cable routing
of NetCol8000-A045. Connect 2U/2V/2W/PE
to another outdoor unit if NetCol8000-A090 is
configured.
3. The outdoor cables are sun- and water-
proofed. It is recommended that tubes be
used for protection.
4. If the outdoor unit is NetCo500-A120,
connect the power cables of the two indoor
units to the QF1 and QF3 of the outdoor unit
respectively.
5. The outdoor unit must receive power from the
indoor unit.
12
Connecting the Outdoor Unit Power Cable
7.2
Connecting the Signal Cable of Outdoor Unit and Indoor Unit
7.3
Perform this operation only for
outdoor units configured with
an intelligent monitoring board.
The outdoor units are
52273539, 52273539-002,
52273541, and 52273541-002.
If the indoor unit is
NetCol8000-A090, connect the
signal cables of outdoor units
to terminals 1, 2, and 3 and
terminals 5, 6, and 7 of X503
respectively.

Upflow
Downflow
Connecting the Equipotential Bonding Cable
7.4
(Optional) Connecting a Differential Pressure Sensor
7.5
1. Secure the differential pressure sensor inside the cabinet using two M3 screws.
2. Connect the longer PU hose to the port without the Lo (-) silk screen under the differential pressure
sensor, and route the hose throughthe top of the cabinet to the supply air pipe plenumchamber.
(There should be two binding pointsadjacentto the pressure inlet.The distance between the
binding pointcloser to the pressure inlet and the pressureinlet shouldnot exceed 25 mm, and the
distance between two binding points is within 20–30 mm.)
3. Connect cables to the differential pressure sensor.
4. After powering on the NetCol8000, choose Settings > System Settings > Indoor Fan, and set Air-
side difference pressure sensor type to 0–500 Pa.
Equipotential bonding point
13

14
(Optional) Connecting the Low-Temperature Component Cables
7.6
(Optional) Connecting the Water
Sensor
7.7
Water sensor cable
(1) Low-temperature component
Low-temperature component
power cable to outdoor unit
Low-temperature component
power cable from outdoor unit
to indoor unit
The figure shows the cable
routing of NetCol8000-A045.
Also connect L/N to another
outdoor unit if NetCol8000-A090
is configured.
(Optional) Connecting the T/H
Sensors Outside Cabinets
7.8
1. Connect the T/H sensor cables.
The T/H sensors in the aisles should be
installed on the door frame of IT cabinets,
and1.5 m (33U) away from the ground.
After the sensor is secured, set the sensor
address according to the following table.
T/H
Sensors
Outside
Cabinets

15
Name Address DIP Switch ID
1 2 3 4 5 6
Cold aisle 1 temp/humid 11 ON ON OFF ON OFF OFF
Cold aisle 2 temp/humid 12 OFF OFF ON ON OFF OFF
Cold aisle 3 temp/humid 13 ON OFF ON ON OFF OFF
Cold aisle 4 temp/humid 14 OFF ON ON ON OFF OFF
Cold aisle 5 temp/humid 15 ON ON ON ON OFF OFF
Hot aisle 1 temp/humid 21 ON OFF ON OFF ON OFF
Hot aisle 2 temp/humid 22 OFF ON ON OFF ON OFF
Hot aisle 3 temp/humid 23 ON ON ON OFF ON OFF
Hot aisle 4 temp/humid 24 OFF OFF OFF ON ON OFF
Hot aisle 5 temp/humid 25 ON OFF OFF ON ON OFF
2. Set the DIP switches on the T/H sensors.
(Optional) Connecting the Teamwork Network Cable
7.9
CAN teamwork networking (CAN Protocol)
1. Prepare the 8pin standard network cable, the cable pin sequence requirements are shown below.
2. Connect the CAN_OUT port of each smart cooling product to the CAN_IN port of the following
smart cooling product using a CAN network cable. After powering on the device, set the Enable
teamwork CAN resistor to Yes for the first and last devices in a teamwork group.
RS485 Monitoring Network Cable (Modbus-RTU Protocol)
1. Make the COM network cable by referring to the following figure.
Except for pins 4 and 5, the
cable of other pins must be cut
off to prevent interference.

•If there is no teamwork control, connect the COM/FE port on each smart cooling product to the
customer's monitoring system. After powering on the device, set the "RS485 monitoring grouping"
to "Enable". Setting path: Settings > Comm Settings > Modbus Settings.
•In CAN networking and no grouping, connect the COM/FE port on the last smart cooling product
to the monitoring device. After powering on the device, set the "RS485 monitoring grouping" of
the last smart cooling product to "Enable". Setting path: Settings > Comm Settings > Modbus
Settings.
2. Group smart cooling products for monitoring based on performance requirements and connect
the monitoring network cables.
•In CAN networking and grouping, connect the COM/FE port on the last smart cooling product in
each monitoring group to the monitoring device. After powering on the device, set the "RS485
monitoring grouping" of the last smart cooling product in each monitoring group to "Enable".
Setting path: Settings > Comm Settings > Modbus Settings.
FE Monitoring Network Cable (SNMP/Modbus-TCP Protocol)
Connect one end of the monitoring network cable (standard network cable) to the FE_1 port or FE_2
on the main control module, and connect the other end to the smart ETH gateway or LAN switch.
16

17
(Optional) Installing the Cap (Applicable to Upflow Units)
7.10
It takes two persons to install the cap using a 2 m step ladder.
Before installing the cap, attach the thermal insulation foam in the accessories to the top beam
of the smart cooling product, and ensure that the reserved holes in the thermal insulation foam
are aligned with the holes in the beam. Check that the cap is intact and free from scratches, that
the sheet metal is not bent, and that the screws are secure.
1. Remove the cap front panel using a Phillips
screwdriver. Place the cap on the top of the cabinet. 2. Secure the left and right sides of the cap
using six M5 screws and the front and
rear of the cap using four M5. screws.
3. Secure the cap front panel to the frame, and
adjust the angle of the front panel blade.
This wiring method applies to the smart module scenarios or other scenarios with LAN switches
regardless of teamwork networking.

9Leak Checking, Vacuuming, and Precharging Refrigerant
Charge 3.0 MPa nitrogen and preserve the system for 24 hours. If the ambient temperatures before
and after the preservation are similar, the system pressure should not drop. If leaks occur after the
preservation, check them along the pipe, especially at the welding positions, needle valve, and angle
valve.
The vacuuming time should be 80 minutes at least and the final pressure (absolute pressure) should
be 60 Pa at most. When the pressure stops dropping, pump for another 10 minutes. After the
vacuumization, close all the vacuum pump and valves. Preserve the system for another 10 minutes
and the pressure (absolute pressure) should be 90 Pa at most. If the pressure gauge cannot be
precise at 60 Pa, ensure that the pressure is displayed at the minimum scale. Extend the preservation
time to one hour. Then check whether the pressure displayed on the pressure gauge increases.
Leak Checking
9.1
Vacuuming
9.2
18
Item
Content
Result
Refrigerant
pipe
Ports are connected properly. The pipeline has oil traps, inverted U
-shaped
traps, gradients (for the refrigerant pipes) , and pipe supports. Pipes are
securely connected. All pipes are wrapped with thermal insulation foam, and
the insulation foam is intact. The needle valve plug is secured (torque of
0.45
±0.05 N.m) , and valve bonnet is tightened. The pipes have no sharp
bends.
□Passed
□
Failed
Waterway
Water pipe joints have been sealed.
The drainpipe is securely connected.
□Passed
□
Failed
Electricity
Cables are not damaged or over
-bent. The power cables and outdoor unit
on/off signal cable,
water sensor, the teamwork cable, and the T/H sensor
cable are connected as required. The rated specifications of the upstream
switch meet the maximum current requirement. All cable connectors
are
secured.
Indoor and outdoor units are properly grounded.
□Passed
□
Failed
Cabinet
The cabinet is installed properly, without any tilt.
The cabinet should be
secured. The foreign matter inside the cabinet such as cable ties and cable
cuts is cleaned up.
□Passed
□
Failed
Compressor
The transport fasteners of the compressor are removed. The bolts on the
compressor are tightened.
□Passed
□
Failed
Air filter
The air filter is correctly installed according to the airflow direction marked on
the frame.
□Passed
□
Failed
Outdoor unit
The fan blades do not interfere
and protective cardboard for fins are
removed. Bonnets of needle valves and water
-proof connectors are
tightened.
Cables are protected by tubes and the cable outlet faces
downward. Glue is applied to the waterproof connector when the outdoor unit
is placed vertically and the waterproof connector faces upward.
□Passed
□
Failed
8Post-Installation Check
1. Remove the vacuum pump from the vacuuming equipment, and replace the vacuum pump with a
refrigerant steel vessel.
2. Partially open the refrigerant steel vessel valve and rubber tube nut. Tighten the nut when you feel
cold air coming out from the nut.
3. Put the refrigerant steel vessel upside down on an electric balance. Clear the reading on the
balance.
4. Open pressure gauge valves, and the refrigerant steel vessel valve to charge refrigerant.
5. The amount of refrigerant charged must be more than half of the total charge amount calculated
and less than the total charge amount. Charge the remaining refrigerant during power-on
commissioning.
6. After refrigerant charging, close pressure gauge valves, and the refrigerant steel vessel valve.
Precharging Refrigerant
9.3

19
Indoor Unit
Outdoor Unit
Refrigerant Charge Amount (L) (L is
total one-
way pipe length
)
0m
＜
L ≤
10m
10m
＜L ≤ 60m
60m
＜L ≤ 100m
NetCol8000
-A045D
NetCol500
-A060/
NetCol500
-
A120 system1/
NetCol500
-A120 system2
9.4
9.4
+ (L-10) ×0.21
9.4
+ (L-10) ×0.28
NetCol500
-A080
13.4
13.4
+ (L-10) ×0.21
13.4
+ (L-10) ×0.28
NetCol8000
-
A045D
including a low
-
temperature
component
NetCol500
-A060/
NetCol500
-
A120 system1/
NetCol500
-A120 system2
32.9
32.9
+ (L-10) ×0.21
32.9
+ (L-10) ×0.28
NetCol8000
-A045U
NetCol500
-A060/
NetCol500
-
A120 system1/
NetCol500
-A120 system2
8.8
8.8
+ (L-10) ×0.21
8.8
+ (L-10) ×0.28
NetCol500
-A080
12.8
12.8
+ (L-10) ×0.21
12.8
+ (L-10) ×0.28
NetCol8000
-
A045U
including a
low
-temperature
component
NetCol500
-A060/
NetCol500
-
A120 system1/
NetCol500
-A120 system2
32.3
32.3
+ (L-10) ×0.21
32.3
+ (L-10) ×0.28
NetCol8000
-
A090D
system1
NetCol500
-A060/
NetCol500
-A120 system1
9.4
9.4+ (L
-10) ×0.21
9.4+ (L
-10) ×0.28
NetCol500
-A080
13.4
13.4+ (L
-10) ×0.21
13.4+ (L
-10) ×0.28
NetCol8000
-
A090D
system2
NetCol500
-A060/
NetCol500
-A120 system2
9.4
9.4+ (L
-10) ×0.21
9.4+ (L
-10) ×0.28
NetCol500
-A080
13.4
13.4+ (L
-10) ×0.21
13.4+ (L
-10) ×0.28
NetCol8000
-
A090D
system1 including a
low
-temperature
component
NetCol500
-A060/
NetCol500
-A120 system1
32.9
32.9+ (L
-10) ×0.21
32.9+ (L
-10) ×0.28
NetCol8000
-
A090D
system2 including a
low
-temperature
component
NetCol500
-A060/
NetCol500
-A120 system2
32.9
32.9+ (L
-10) ×0.21
32.9+ (L
-10) ×0.28
If the R410A refrigerant is provided by Huawei, put the refrigerant steel vessel upside down when
charging in the refrigerant. If the refrigerant is not provided by Huawei, check with the refrigerant
provider whether the steel vessel has a siphon. If the vessel has a siphon, put it upside up when
charging in refrigerant. If the vessel has no siphon, put it upside down when charging in refrigerant.
These measures ensure that the refrigerant is charged in the liquid form.
If one NetCol8000-A090D is used with two NetCol500-A060s (or one NetCol500-A120) and the L
is 80 m, the 9.4 + (80-10) ×0.28=29 kg needs to be filled in each compressor system. In total, the
NetCol8000-A090D needs to charge 58 kg R410A.
NOTE

20
Low-pressure needle valve
Exhaust pipe
needle valve
Nut
Reducing valve
Nitrogen cylinder
Electronic
scale
Refrigerant cylinder
Vacuum pump
Nut
Reducing valve
Nitrogen cylinder
Electronic
scale
Refrigerant cylinder
Vacuum pump Low-pressure needle valve
Exhaust pipe needle valve
Liquid pipe needle valve
1. Leak checking
2. Vacuuming
3. Precharging refrigerant
1. Leak checking
2. Vacuuming
3. Precharging refrigerant
•Left pressure gauge is low pressure gauge. Right
pressure gauge is high pressure gauge.
•The specification of needle valve is 7/16-20UNF.
NOTE
Scenarios without a low-temperature component (Downflow)
Scenarios without a low-temperature component (Downflow)
The figures use a single-system unit as an example. You need to perform leak checking,
vacuuming, and precharging refrigerant on both systems of a dual-system unit.