49
3.5
Laying and connection of cooling lines
IMPORTANT: The presence of dirt or water inside the pipes
to be used for the cooling lines could have a negative effect
on the applianceis correct running. Normal copper pipes for
thermohydraulic purposes do not offer the necessary
garantees for such a task. It is therefore essential to use
copper pipes for cooling purposes only which have
been cleaned and sealed within the factory. Such pipes
are annealed and delivered in rolls with the ends sealed.
Before assembling and after cutting off the required pieces
it is essential to seal both the ends of the roll and of the cut-
off pieces. Furthermore, the installation may be quickened
by using preinsulated refrigeration copper pipes which do
not require further lagging.
Granted that the pipes employed have to have the same
diameters and thicknesses as indicated in paragraph 2.2
"Technical Particulars", the installation and connection of
the lines must be carried out according to the following
procedure:
a) Identify the shortest route linking the internal and external
unit creating as few bends as possible (the shorter the
route and the fewer the bends, the better the applianceis
output). The length of the internal unit connecting lines
(or of the lines connecting up all the internal parts of the
Multisplit) must not be more than 15 m in each direction
(in any case, for more than 10 m it is necessary to top up
the charge with 20 g of R410A for each extra meter).
b) Cut off the required piping - it is better to cut off a little
more than required - and seal the ends.
IMPORTANT: The pipes should on no account be cut with
a saw as the shavings could get into the piping. The cutting
should therefore be carried out using a wheel pipe cutter
(fig. 14).
c) Insert the pipes into the lagging sheaths if preinsulated
pipes are not used. Each sheath end must be joined and
sealed with adhesive tape. The lagging sheaths must be
made of polyurethane closed cell foam and must have
the following characteristics:
-
maximum trasmission coefficient: 0,45 W(Kxm
2
) or
0,39 kcal/(hx
°
Cxm
2
),
-
the liquid lines must have a thickness of at least 7
mm,
-
the gas lines must have a thickness of at least 10
mm. Avoid putting both lines into the same lagging:
the applianceis efficiency could be compromised as
a result.
d) Lap the lines with the raceway within which the electrical
cables are housed (see paragraph 3.7) fixing it with
adhesive tape or plastic clamps at regular intervals.
e) Lay down the piping from the internal unit through to the
external unit (or vice versa) making sure that the lagging
does not get damaged in any way when passed through
the walls.
f)
If the piping is not connected up to the appliance
Fig. 14
