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CONNECTION PIPES
The pipes are wound and already flared at both ends. The dimensions are those
given in the "LIMITS TO THE LENGTH AND HEIGHT DIFFERENCE OF
COOLANT PIPES" section.
Route the coolant pipes as required, with as few bends possible. Use an
appropriate pipe bender and comply with a minimum bending radius to prevent
them from being squashed. Remember that the bending radius must not be less
than 3.5 times the outer diameter of the tube (Fig. 4).
If you do not wish to cut off any excess pipe after routing, wind it up so that the coil
axis is horizontal.
Bear the following indications in mind when installing the pipes:
• Take care to unwind the pipe in the direction in which it was wound.
• Wrap the two pipes together with tape before passing them through the holes in
the wall to prevent the insulation from being damaged and dust from infiltrating.
To facilitate this operation, it is advisable to insert a piece of PVC pipe of a sui-
table diameter and the same length as the wall thickness, into the hole in the
wall.
Adequate materials must be selected since the operating pressure values are sen-
sibly higher than those of the R22 refrigerant.
The following table gives the thickness values of the recommended copper pipes
in relation to the nominal diameters of the connecting lines. Do not use pipes
whose thickness is less than 0.8 mm.
If the pipes are longer than the effective requirements, they can be cut and
re-flared by operating in the following way:
If the pipes are longer than necessary, they can be cut and flared again as descri-
bed below:
1.Pipe cutting
Use a pipe cutter (Fig. 5).
Proceed with care when cutting the pipe so as to prevent it from becoming defor-
med. Cut the pipe to the required length (the cut must be horizontal).
2.How to remove burrs or splinters
Refrigerant could leak if the surface of the flare is warped or splintered. It is advi-
sable to remove the burrs by holding the pipe end downwards (Fig. 6).
Remove the burrs and trim the surface of the cut edge.
3.Insert the union
Remember to insert the union before flaring the pipe (Fig. 7).
4. Pipe flaring
Make sure that the pipe and swaging machine are clean.
Remember to comply with the instructions in the following tables ("Re-flanging
thickness" and "Flare and Union dimensions") when flaring the pipes.
Clamp the pipe (2 Fig. 8) in a vice (1 Fig. 8) and begin to flare it (it is best to place
a drop of refrigerating oil between the rubbing parts).
Installation instructions