REXNOVA ISA 20 BITHERMAL, Installation, Use And Maintenance Manual

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COMBUSTION GAS EVACUATION SYSTEM: INSTALLATION
The boiler, based on its UNI 7129 classification,
can be connected to COAXIAL intake and
flue evacuation systems.
The “coaxial” system is composed of a single
pipe containing both the flue and intake pipes
on the same axis. The system provides for all
The length of this system is limited by
its large pressure drops. The maximum
possible length therefore depends on
the components used to create the line
and can be determined by adding the
“Equivalent lengths” for each individual
component used (excluding the initial 90°
elbow) listed in the “COAXIAL SYSTEM”
table.
IT IS ESSENTIAL NOT TO EXCEED THE MAXIMUM
PERMISSIBLE LENGTH!
Consult the maximum length values
listed in the “FLUE SYSTEM TECHNICAL
CHARACTERISTICS” at page 16 for COAXIAL
systems relative to the type of device
installed.
The “split” flue system consists of one pipe
for combustion gas evacuation connected
to the fan outlet and one pipe for the air
intake connected to the hole on the roof
of the sealed chamber. The system provides
60/100 mm DIIAMETER COAXIAL SYSTEM
components necessary for completing the
line, including changes of direction, straight
sections of various lengths, connections to
the boiler and outside terminals as well as all
necessary seals. Below is a list of compatible
components with the relevant features:
for all components which are needed for
completing the line, including changes
of direction, straight sections of various
lengths, connections to the boiler and
outside terminals as well as all necessary
seals, for both pipes. Below is a list of
compatible components with their relative
characteristics.
No. Description Pressure drop (Pa) Equivalent length m
1 Terminal L.990 25 2.8
2 Extension L.1000 M-F 6 1
3 Vertical flanged coupling M 15 2.2
4 90° elbow M-F 7 1.3
5 45° elbow 6 1
6 d 128 Neoprene gasket d 128
7 d 100 Intake gasket d 100
8 d 60 Flue evacuation gasket d 60