Operating Principle - REMEHA 610 ECO Technical Information

3.2 Operating principle of each module
Combustion air is drawn into the inlet connection from
the plant room (room ventilated version) or from outside
via the eccentric flue system (room sealed) by the air
supply fan of each boiler module.
On the inlet side of the fan is a specially designed
chamber (venturi unit) which takes gas from the multi-
block and mixes it in the correct proportions with the
incoming air. This mixing system ensures that the cor-
rect gas/ air ratio is delivered to the pre-mix burner at all
times.
Depending on demand (under the dictates of flow/return
sensor and other external/internal control inputs) the
'abc ' system of each boiler module determines the
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required output of the boiler module. The 'abc
trol then varies the speed of the air supply fan which
alters the volume of air being drawn into the venturi, this
change in volume is measured using air pressure dif-
ferential which directly controls the volume of gas also
being delivered to the venturi. The resultant controlled
mixture is delivered to the premix burner.
This mixture is initially ignited by the combined ignition/
ionisation probe, which monitors the state of the flame.
Should the flame be unstable or not ignite within the
pre-set safety time cycle the controls will (after 5
attempts) shut the boiler module down requiring manual
intervention to reset the boiler module. The digital dis-
play will indicate a flashing fault code confirming the
reason for the failure.
The products of combustion in the form of hot flue gases
are forced through the heat exchanger transferring their
heat to the system water, (the flue gas temperature is
reduced to approximately 5/ 8° above the temperature
of the system return water) then discharged via the con-
densate collector, to the flue gas outlet connection, to
atmosphere.
Because of the low flue gas exit temperature there will
be a vapour cloud formed at the flue gas terminal -this
is not smoke-, simply water vapour formed during the
combustion process.
If the flue gas temperature falls below dew point (55°),
water vapour (created during the combustion process)
will begin to condense out in the boiler module, trans-
ferring its latent heat into the system water, thereby
increasing the output of the boiler module without
increasing the gas consumption.
Condensation formed within the boiler modules and
flue systems is discharged from the boiler module to an
external drain via the drain pans and siphons supplied.
The flue gas discharges of the separate modules come
together in the flue gas collector, which can be connect-
ed horizontally as well as vertically.
Each boiler module can be supplied, as an option with
a second (constant temperature) return connection.
This additional connection enables the boiler
module to make full use of its condensing ability
whilst accepting both fixed and variable temperature
returns from the same system. A condensate
collector is situated above the flue gas collector.
This condensate collector is connected to 1 of the
siphons. fig. 01
' con-
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Remeha Gas 610 ECO