03.5 STOVE EFFICIENCY
Highly efficient stoves may pose difficulties for fume extraction.
In order for a flue pipe to work properly its internal temperature must increase as a consequence of the fumes generated during combustion.
Importantly, the efficiency of a heater is determined by its ability to transfer most of the heat produced to the environment to be heated: consequently, the greater
the efficiency of the stove, the "colder" the residual fumes of combustion, and consequently, the lower the "draft".
A traditional chimney flue, with a rough design and insulation, is more efficient if used with a traditional open fireplace or a poor-quality stove where most of the
heat is lost with the fumes.
Therefore, purchasing a quality stove often entails modifying the existing chimney flue to obtain a better insulation, even when it already works properly with old
appliances. Poor draught results in the stove not operating when hot or in smoke spillage.
Connecting the stove pipe to an existing chimney flue that has already been used with an old appliance is a common mistake. In this way two solid-fuel appliances
share the same chimney flue, which is wrong and dangerous.
If the two appliances are used simultaneously, the fume load might exceed the existing chimney flue capacity resulting in downdraught. If only one appliance is
used, the fume heat will facilitate draught but the cold air coming from the other appliance not in use will cool down exhaust fume temperature again blocking the
draught.
Besides the problems described so far, if the two appliances are placed on different levels the communicating vessel principle might be interfered with, causing
combustion fumes to be drawn in an irregular and unforeseeable way.
03.6 INSTALLATION
Follow the instructions below before installing your stove.
Select the position where the stove is to be installed and:
•
Arrange the connection to the flue pipe for fume extraction.
•
Provide the external air intake (combustion air) and check for its presence: it must be drawn from a free space (not spaces where extractor fans exist or
without ventilation) or from outside.
•
Arrange a discharge pipe for the condensate resulting from boiling.
•
If possible, install it near the hydraulic manifold or however, in a suitable position so that you can easily connect it to the hydraulic system.
•
Place the stove on the floor in a convenient position for the connection to the flue pipe and close to the combustion air intake.
•
The appliance must be installed on a floor with an adequate loading-bearing capacity. Should the existing floor not comply with the requirement above, proper
measurements must be taken (for instance, the installation of a load distribution plate).
•
All the structures which could catch fire if exposed to excessive heat must be protected. Floors made from wood or inflammable materials must be protected
using non-combustible materials (e.g. 4mm-thick sheet metal or ceramic glass).
•
The appliance installation must ensure easy access for cleaning the stove, exhaust pipes and flue pipe.
•
This appliance is not suitable to be installed on a shared flue pipe.
•
During normal operation, the stove draws air from the room where it is installed. Therefore, an external air intake must be positioned at the same height of
the pipe located on the stove back. When it is operational, the stove can cause a negative pressure in the room where it is installed. Therefore there should
not be other naked flame devices in the same room.
•
If the stove is to be installed in rooms where it is surrounded by combustible materials (e.g. furniture, wood cladding, etc.), the following minimum clearances
must be complied with:
SAFETY DISTANCE FROM COMBUSTIBLE
MATERIALS:
REAR WALL C = 0 mm
INSULATION THICKNESS C = 80 mm
SIDE WALL = 600 mm
RECESS B= 5 mm
FRONT R = 1000 mm
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