Operating Principle - DeDietrich C 230 ECO Installation And Service Manual

3.4 Operating principle

A venturi is placed to the side of the fan inlet. The air and gas are
mixed in here at a constant ratio.
The fan carries out a pre-sweep if there is a heat request. The fan
sucks in the combustive air which will be optimally mixed with the gas
in the venturi. The homogenous air/gas mixture is fed into the burner
by the fan.
The mixture is ignited by the ignition/ionization combination electrode
which also monitors the flame.
Boiler output is set according to the settings and temperatures of the
water measured by the temperature sensors. When the combusted
gas temperatures are lower than the dew point (approx. 55°C, the
temperature as of which the steam in the combusted gases starts to
condense), the steam in the combusted gases will condense in the
lower part of the heat exchanger. The heat released during this
condensation process (so-called latent or condensation heat) is also
transferred to the central heating water. The condensed water is
discharged via the siphon in the lower section of the heat exchanger.
The combusted gases go into the condensates collector and are
evacuated via the combusted gas evacuation duct.
To provide continuous heat, the boiler requires a minimum of 30% of
the water flow rate at a T of 20 K at nominal output, high stage. The
boiler can be ocnstructed with a second return (accessory). This
second return can provide additional efficiency when various
temperatures are present in the installation.
The DIEMATIC-m3 control panel controls the room temperature in
accordance to the outside temperature by action on the burner.
Heating regulation is controlled by the influence of the regulator on
the burner, the pumps and, if installed, the mixing valve(s).
Connecting a remote control with room sensor or an interactive
remote control CDI 2 also enables self adaptivity of the gradient and
the parallel offset of the heating curve.
The "installation anti-freeze" function is active regardless of the
operating mode. It is triggered as soon as the outdoor temperature
reaches the limiting value preset to +3°C (see paragraph: Further
information on various parameters).
The domestic hot water is regulated by the regulator acting on the
load pump through the DHW sensor. The DHW loop can be handled
by the S.AUX1:, S.AUX2: or S.AUX3: outlet (Heating according to
the time programme).
The DIEMATIC-m3 control panel includes the "anti-legionella"
protection option
See: Control panel instructions (Installer parameters: LEG
PROTEC).
In a cascade installation, the K3 control panel is intended to be fitted
to the secondary boilers.
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03/10/2012 - 300015171-001-01 C 230 ECO