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INDUSTRY
Section 4
Installation
To make the refrigerant connection between the chilling
cabinet and the remote condensing unit it is necessary
to install the piping of the liquid and suction line accord-
ing to the diameters of the ballcocks present on the
machine/partly completed machinery.
The recommended diameters and gas charges are as
follows:
Up to 15 m equivalent length of the line in the case of
unibody machines with remote unit.
Up to 25 m of equivalent length of the line in the case
of panel machines.
For lengths greater than those indicated it is necessary
to re-dimension the diameters of the line. The pipes
must be supported on the wall in the vicinity of the
bends or welding and every 2 m of straight section. The
joints between the pipes must be hermetically sealed
by brazing with suitable filler alloy.
If R744 is used as refrigerant fluid, it is necessary to
convey the discharge of the safety valve, placed to
protect the chilling cabinet, to the outside; use the
appropriate diameter of the pipes. The additional
requirements for R744 refrigeration systems indicated in
annex A of EN 378-2 are the installer's responsibility.
4.6.4 REFRIGERANT CONNECTION
WARNING!
All refrigerant lines must be designed to allow correct oil
return to the compressor.
If the condensing unit is positioned above the evaporator
it is necessary to insert siphons at a height of every 2
metres on the vertical line section and a counter-siphon
having reaching the end of the ascent section.
When there are horizontal line sections it is important
that the suction pipes have a slope of at least 3%
towards the condensing unit in order to facilitate the
return of the oil to the compressor.
If the condensing unit is positioned below or at the same
height as the cabinet, no siphon must be used, but it
is sufficient to guarantee the slope of the pipes for the
condensing unit.
If the line is very long, it is necessary to keep the oil level
under control at the first start-up and in the following
days and top up if necessary.
4.6.4.2 OIL RETURN
•
•
In the event that the refrigeration circuit is insulated
from the space occupied by a ventilated enclosure,
the installer will be responsible for sizing according
to 378-2 in clause 6.2.14.
The personal protective equipment required in these
phases is:
Slope
2%
2000
2000
Slope
2%
Insulate the suction piping with anti-condensation pipe
with a minimum thickness of 19 mm. If the refrigerant is
R744 it is also necessary to insulate the liquid piping.
4.6.4.1 INSULATION OF REFRIGERANT LINES
