4.6 Vacuuming
(1) Connect the manifold gauge and the charging hoses to the check joints of the stop valves with a
vacuum pump.
(2) Vacuum the refrigerant piping of the system with the vacuum pump until the pressure reaches -0.1MPa
or lower. And then, continue the vacuum pumping work for more than one hour.
(3) After that, turn off the vacuum pump and then observe the pressure for more than two hours.
(4) If the pressure is higher than -0.1MPa obviously, the gas leak is suspected. Please check the leak
position and eliminate it. Then repeat the vacuuming work again.
◆
The vacuuming should be performed on the gas stop valve and the liquid stop valve simultaneously.
Otherwise, air may be left in the system and lead the system to be damaged.
◆
The tools are used for exclusive use of R410A.
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Never use the refrigerant charged in the outdoor unit for air purging.
Insufficient refrigerant will lead to failure.
Insulate the liquid pipe for prevention
of the capacity decrease according to
the ambient air conditions and
the dewing on the pipe surface by the
low pressure.
Check to ensure that there is
no gas leakage. When large amount
of the refrigerant leaks, the troubles
as follows may occur;
1. Oxygen Deficiency
2. Generation of Harmful Gas Due to
Chemical Reaction with Fire.
!
!
!
At the test run, fully open the spindle.
If not, the devices will be damaged.
An excess or a shortage of refrigerant is the main cause of trouble to the units.
Charge the
!
correct refrigerant quantity according to the description of label at the inside of
service cover.
Check for refrigerant leakage carefully. If a severe refrigerant leakage occurs, it will cause
difficulty with breathing, or harmful gases would generate when there is open fire in the
room.
