Specifications

SiBE28-805 Test Operation
Test Operation 67
1.2.3 Leak Test and Vacuum Drying
The units were checked for leaks by the manufacturer.
After connecting the field piping, perform the following inspections.
1.2.3.1 Preparations
Referring to figure 19, connect a nitrogen tank, a cooling tank, and a vacuum pump to the
outdoor unit and perform the airtightness test and the vacuum drying. The stop valve and valve
A in figure 19 should be open and closed as shown in the table below when performing the
airtightness test and vacuum drying.
1.2.3.2 Airtightness Test and Vacuum Drying
Note:
Make sure to perform airtightness test and vacuum drying using the service ports
of the stop valves of the liquid side and of the gas side. (For the service port
location, refer to the "Caution" label attached on the front panel of the outdoor
unit.)
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See "1.2.5.3 Stop valve operation procedure" on page 70 for details on
handling the stop valve.
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To prevent entry of any contamination and to prevent insufficient pressure resistance,
always use the special tools dedicated for working with R-410A refrigerant.
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Airtightness test:
Note:
Make sure to use nitrogen gas.
Pressurize the liquid and gas pipes to 4.0 MPa (40 bar) (do not pressurize more than 4.0 MPa
(40 bar)). If the pressure does not drop within 24 hours, the system passes the test. If the
pressure drops, check where the nitrogen leaks from.
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Vacuum drying: Use a vacuum pump which can evacuate to –100.7 kPa (5 Torr, –755 mm
Hg)
1. Evacuate the system from the liquid and gas pipes by using a vacuum pump for more than 2
hours and bring the system to –100.7 kPa. After keeping the system under that condition for
more than 1 hour, check if the vacuum gauge rises or not. If it rises, the system may either
contain moisture inside or have leaks.
State of the valve A and the stop valve Valve A
Liquid side
stop valve
Gas side
stop valve
Performing the airtightness test and
vacuum drying
Open Close Close
fig. 19
Pressure
reducing valve
Nitrogen
Tank
Siphon system
Measuring
instrument
Vacuum
pump
Valve A
Gas line stop valve
Liquid line
stop valve
Stop valve
service port
Charge
hose
Outdoor unit
Indoor
unit
Indoor
unit
Dotted lines represent on site piping
To indoor unit