Rendamax R3456 EVO, Manual, Page: 6 / 72

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Gas condensing boiler R3456 EVO
Technical description
Technical Description
The R3456 EVO is a fully modulating
condensing boiler. The control unit of
the boiler adapts the modulation ratio
automatically to the heat demand re-
quested by the system. This is done by
controlling the speed of the fan. As a
result, the whirlwind mixing system will
adapt the gas ratio to the chosen fan
speed, in order to maintain the best
possible combustion figures and there-
with the best efficiency. The flue gases
created by the combustion are trans-
ported downwards through the boiler
and leave at the back side into the
flue system.
The return water from the system en-
ters the boiler in the lower section,
where is the lowest flue gas tempera-
ture in the boiler. In this section con-
densation takes place. The water is
being transported upwards through the
boiler, leaving the boiler at the top
(burner) section. The cross flow work-
ing principle (water up, flue gas down)
ensures the most efficient results.
The LMS14 control unit can
control the boiler operation based
on:

Fixed flow temperature;

weather compensated
operation (with optional
outdoor sensor);

0-10V external influence
(temperature or capacity) from
a building management
system.
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1 LMS14 boiler management unit
(HMI)
2 Speed controlled Venturi gas/
air mixing system
3 Water cooled premix burner
4 Water cooled stainless steel
heat exchanger :
3 levels for R3400 EVO and
R3500 EVO versions
5 Water cooled stainless steel
heat exchanger :
4 levels for R3600 EVO version
6 Pilot mixing system
7 Main mixing system