27.08.2018
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EVO S -
Installation and Servicing
Single boiler
1 non-regulated circuit with sliding flow
Diagrams
VF20, VF21,
VF21bis
page 1 / 5
A. HYDRAULIC DIAGRAM
figure 26 -
VF20 diagram
The boiler operates in variable flow temperature according to the outdoor temperature measured by the
exterior sensor QAC 34.
The heating water law is programmed on the NAVISTEM B3000, with or without a low temperature limit
and with a weekly programme.
The flow rate of the heating pump, in m
3
/h, is adjusted to the real needs of the installation and, as a
minimum, to P/25, with P power in th/h of the boiler.
If the heating pump is variable-flow rate, it must be set to a constant flow rate to deliver the minimum flow
required by the generator.
If the installation is equipped with thermostatic taps on the emitters, the bypass between the outward and
return lines of the network is essential. It is equipped with a differential valve that allows for the free flow of
the heating pump when the thermostatic taps close.
