Appliance Installation - Saunier Duval ISOTWIN CONDENS F 35 E Instructions For Use, Installation & Servicing

5 Appliance installation

All the dimensions in this chapter are
expressed in mm.
5.1 Recommendations before
mounting
5.1.1 Domestic hot water circuit design
The circuit should be designed to avoid
any unnecessary flow losses (decrease
the number of elbows).
The boiler will operate with a minimum
supply pressure but with a low flow.
Optimum performance will be achieved
with a pressure of 1 bar.
5.1.2 Heating circuit design
ISOTWIN CONDENS boilers can be used
for any kind of installation: serial or
derivated double tube, single tube, hot
floor, etc...
Heating surfaces can be made up with
heaters, convectors or unit heaters.
Warning: If the materials used are of
a different type, some corrosion can
occur. In that case, we advise you to
add an inhibitor to the heating circuit
water (according to the manufacturer's
recommendations) that could avoid gas
production and oxide formation.
The pipework sections should be fixed by
using the following flow/pressure curve
(see chapter "Heating circuit adjustment").
The system will be calculated according
to the flow corresponding to the power
that is really required without taking into
account the maximum power that the
boiler can supply. Nevertheless, we advise
you to have a flow big enough so that the
temperature difference between outgoing
and return is under or equal to 20°C. The
minimum flow rate is indicated in the
chapter "Technical Data" at the end of this
instruction manual.
The piping route should be designed in
such a way that it avoids any air locks
and make purging of gas from the system
easier. Bleeders should be placed at each
high point of the system as well as on any
radiators.
Total water volume accepted by the
heating circuit depends, amongst
other things, on the cold static load.
The expansion tank fitted in the boiler
is delivered factory set (see chapter
"Technical Data" at the end of this
instruction manual). At commissioning, it
is possible to change this pressure in case
of a larger static load. We advise you to
provide a drain valve at the lowest point of
the system.
If thermostatic radiator valves are used,
we advised you not to fit in a room where
a room thermostat is fitted.
• In case of an old installation, flush the
heating system before installing the
new boiler.
• If the boiler is not immediately installed,
protect all the pipe fittings so as to
avoid that any plaster or paint that
could impede the connection.
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