Samsung AM***XMDCH Series Installation Manual page 25

Vacuuming a pipe and an indoor unit
Use the tools for R410A only to prevent the inflow of foreign substances and resist
against the internal pressure.
Use the vacuum pump with the check valve to prevent pump oil from flowing
backward while the vacuum pump is stopped suddenly.
Use the vacuum pump that can be vacuumed up to -100.7 kPa (gauge pressure),
5 torr.
Close the service valve of the liquid side pipe, gas side pipe completely when
performing air tightening test or vacuum drying.
Connect the manifold gauge to the liquid
pipe and gas pipe.
Vacuum the liquid pipe and gas pipe
using the vacuum pump.
Vacuum those pipes for more than 2 hours
and 30 minutes.
Close the valve after checking the vacuum
gauge pressure has reached at -100.7 kPa
(gauge pressure), 5 torr.
Check whether the pressure is maintained
as -100.7 kPa (gauge pressure), 5 torr. for
an hour.
Pressure Increase
No
Charging additional refrigerant
according to piping length
No
If the pressure rises in an hour, either water remains inside the pipe, or there will be a leak.
CAUTION
Make sure to install check valve to prevent pump oil from
flowing into the pipe.
The time of vacuum drying may differ depending on the
length of the pipe or outdoor temperature.
Perform vacuum drying for at least 2 hours and 30 minutes.
Check the vacuum pressure using the vacuum gauge.
Check the gas leak.
Yes
Vacuum destruction due to the moisture
inside the pipe
Apply pressure with Nitrogen gas of 0.05
MPa (gauge pressure), 7.25 psig.
Perform vacuum drying again up to
-100.7 kPa (g auge pressure), 5 torr
hours or longer) and evaluate the vacuum.
Pressure Increase
Vacuum
pump
(for 2
Yes
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