Make sure the refrigerant piping and branch joints
are completely insulated.
Make sure the liquid and gas pipes (for all units) are
insulated.
Use heat-resistant polyethylene foam for the liquid
pipes (able to withstand temperature of 70°C), and
polyethylene foam for the gas pipes (able to
withstand temperature of 120°C).
Reinforce the insulation layer of the refrigerant piping
based on the installation environment.
After the leak test and the vacuum drying are
completed,the pipe must be insulated. Considerations:
Calculating additional refrigerant charge
The additional refrigerant charge required depends on
outdoor unit model, MS box model and the lengths and
diameters of the outdoor and indoor liquid pipes. Table
5-3 to 5-5 show the additional refrigerant charge
required under different conditions.
Fig. 5-18
5.8 Piping Insulation
5.9 Refrigerant Charging
Pressure gauge
Master unit
Slave unit
Slave unit
Field piping
3
2
1
3
2
1
Vacuum pump
Low pressure gas pipe stop valve
High pressure gas pipe stop valve
Liquid pipe stop valve
Condensed water may form on the surface of the
insulation layer.
|+¡X
+¡`+
]`
]
]
] `
Piping size
Humidity<80%RH
Thickness
;&]X¢;
Thickness
Use only R410A as the refrigerant. Other
substances may cause explosions and
accidents.
R410A contains fluorinated greenhouse
gases, and the GWP value is 2088. Do not
discharge the gas into the atmosphere.
When charging the refrigerant, make sure
you wear protective gloves and safety
glasses. Be careful when you open the
refrigerant piping.
WARNING
If the power supply of some units is off, the
charging program cannot be completed
normally.
If this is a multi-unit outdoor system, the
power supply for all outdoor units should be
turned on.
Make sure the power supply is turned on 12
hours before operations so that the
crankcase heater is properly energized. This
is also to protect the compressor.
NOTE
Make sure all connected indoor units have
been identified.
Charge the refrigerant only after the system
has not failed the gas tightness tests and
vacuum drying.
Volume of refrigerant charged must not
exceed the designed amount.
NOTE
Table 5-3. Additional refrigerant charge amount R1
(according to outdoor unit model)
8HP
10HP
12HP
14HP
16HP
18HP
2
2
2.6
4.9
5.5
5.7
Additional refrigerant charge
per model (kg)
Outdoor unit model
Table 5-4. Additional refrigerant charge amount R2
(according to MS box model)
MS01
MS04
MS06
MS08
MS10
MS12
0.1
0.5
0.5
1
1
1
Additional refrigerant charge
per model (kg)
MS box model
Table 5-5. Additional refrigerant charge amount R3
(according to liquid pipe lengths and diameters)
|`
_`
{
`_
_
`+
X|
0.022
0.057
0.110
0.170
0.260
0.360
0.520
0.680
Additional refrigerant charge per
meter of equivalent length of
liquid piping (kg)
Liquid piping
Diameter
(mm OD)
24
