Samsung ACC2400C - Manual (Page 50)

Performing Leak Tests
Before completing the installation (insulation of the hose and piping),
you must check that there are no gas leaks.
To check for gas leaks on the... Then, using a leak detector,
check the...
Indoor unit Flare nuts at the end of sections
A and B.
Outdoor unit Valves on sections C and D.
C
D
A
B
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