29
MYDENS
COSMOGAS
5 - INSTALLATION
a
WARNING!!! With C43 and C63 exhausts, the
condensate coming from the chimney cannot be
conveyed into the appliance. The appliance cannot
have the air intake and flue exhaust on opposite
walls of the building;
- C83, separated with wall intake or another point
independent from the intakes of other appliances, and flue
exhaust;
- C93, separated with exhaust on roof and intake in pre-
exisisting channel;
During operation (especially in winter) it is possible that
white smoke may emerge from the appliance’s flue
exhaust because of its high performance.This is a natural
phenomenon and is not a cause for concern, beacuse it is
the water vapour in the flue gas which condensates when it
comes in contact with the outside air.
5.17.1 - Type of intake/exhaust B23 and
B23P
In the case of B23 and B23P type combustion agent air
intake/flue exhaust systems, it is essential that the rooms in
which the appliances are installed have at least as much air
as is required for combustion and ventilation of the room. It
is therefore useful to remember that the combustion of 1 m³
of gas requires 11 cm³ of air.
The natural flow of air must take place directly through
permanent openings made in the outside walls of the room
to be ventilated, however they must be away from sources
of pollution: vents of dubious origin, airborne industrial
exhausts, etc.
The ventilation openings must meet the following
requirements:
- Cross-sections with net passage of at least 6 cm
2
for
every kW of heat input installed, with minimum of 100
cm
2
;
- Constructed in a way that the opening inlets both inside
and outside the wall cannot be blocked;
- Be protected, for example with grids, mesh, etc. The net
passage cross-section must not be reduced by these
systems;
- Be positioned at a height near to floor level and in such
a way as not to cause any problems with the operation
of the flue exhaust devices; where this position is not
possible, the cross- section of the ventilation openings
must be increased by at least 50%;
The air flow can also be obtained from an adjoining room
provided that:
A - It has direct ventilation;
B - In the room to be ventilated, only appliances fitted to
exhaust ducts are installed;
C - The adjacent room is not a bedroom;
D - The adjacent room is not a communal part of the
building;
E - The adjacent room is not an environment with fire
hazards such as hangars, garages, warehouses for
combustible materials, etc.;
F - The adjacent room does not have a negative pressure
with respect to the room to be ventilated due to reverse
draught (which can be caused by another appliance
operating with any type of fuel in the same room, or
a fireplace or any other intake device for which an
adequate air intake has not been provided for);
G - The flow of air from the adjacent room to the room to
be ventilated can take place freely through permanent
openings, with a total net cross-section not less than that
indicated at the start of this section.
In rooms where gas appliances are installed, it may
become necessary to evacuate stale air, as well as
introducing combustion agent air, the result being the
release of an additional equal amount of clean air.
If the stale air is evacuated with the aid of a mechanical tool
(electric fan), the following conditions must be respected:
A - If there is a common exhaust duct in the room that is not
in service, it must be capped;
B - The ventilation opening in the room in which the gas
appliance is installed must be increased, depending on
the maximum air flow rate required at the electric fan;
C - The action of the electric fan must not affect the correct
evacuation of the combustion products. Check all of the
above running a draught test, run the fan or extractor
hood at its maximum power and the gas appliance at the
maximum and minimum power.
