Daikin VRV II Series, Design, Installation & Testing Instructions, Page: 23 / 242

Si39-303 Installation
General Information 17
3.2.3 Refrigerant Pipe Work
!
Operational steps
The 3 Principles
of Refrigerant
Piping
The “3 principles of refrigerant piping” must be strictly observed
Fit pipes
provisionally
Install indoor unit
Solder Flushing Air tight test Vacuum drying
Cut pipes to size Replace nitrogen
(V0963)
The 3 principles of refrigerant piping
Dry Clean Air tight
Make sure there is no moisture
inside the pipes Make sure there is no dirt inside the
pipe Make sure the refrigerant does not
leak out
Actoin to avoid problem Cause of problem
l
Rainwater, work water,
etc. gets into pipes from
outside
l
Moisture generated inside
pipes due to condensation
l
Formation of oxides inside
pipes during soldering
l
Dirt, dust or other
extraneous material gets
into pipes from outside
l
Leak from soldered area
l
Leak from flared area
l
Leak from flange area
Pipe covering Flushing
Replace nitrogen
Pipe covering
Air tight test
Flushing
Vacuum drying
Use the proper materials (copper pipe,
solder, etc.)
Adhere strictly to standard soldering
work practice
Adhere strictly to standard flaring work
practice
Adhere strictly to standard flange
connection work parctice
Clean
Dry
Air tight
(V0964)