Operating Principle - elco R3400 Notice D'installation Et D'emploi

Construction
Layout of boiler

Operating principle

Operating principle
The R3400/R3500/R3600 is a fully
modulating 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
4
34
the boiler and leave at the back side
into the chimney connection.
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, in order to leave the boiler at the
top (burner) section. The cross flow
working principle (water up, flue gas
down) ensures the most efficient com-
bustion results.
Layout of boiler
The R3400/R3500/R3600 boiler con-
sists of the following main components:
1 Return water connection
2 Flue gas connection
3 Water flow switch
4 Safety valve
5 Flow water connection
6 Filling/draining valve
7 Top plate
8 Plenum
9 Burner
10 1st Heat exchanger
11 Gas filter
12 2nd Heat exchanger
13 Gastrain
14 Frame
15 180° Bend
16 Compensator
17 Flue gas connection
18 Condensate receptacle
19 Flue gas receptacle
20 Combustion chamber
21 Entry electrical connections
22 Syphon
23 Main gas valve
24 Fan
25 Electrical box
26 Control panel
27 Casing
28 Air inlet damper
29 Butterfly valve
30 Main mixing channel
31 Pilot gas valve
32 Pilot mixing channel
33 Boiler pump
34 3rd Heat exchanger (only R3600)
A Air
B Gas
C Flue gasses
D Condensate
The KM628 control unit can control the
boiler operation based on:

fixed temperature (stand alone
operation);

weather compensated operation (with
optional controller);

with 0-10V external influence
(temperature or capacity) from a buil-
ding management system.