Hot Air Distribution System; Gravity System For Hot Air Distribution; Forced System For Hot Air Distribution - Defro Home INTRA Series Operating Manual

made of non-flammable materials
80 mm
80 mm
housing
decompression
grille
decompression plate made
of non-flammable materials
hot air outlet grille
insulation made
of non-flammable
materials
20-30 mm
air inlet grille
Picture 27. Exemplary installation of fireplace insert.
Nonetheless, if you are not sure about the design of floor slab,
where the fireplace insert is to be installed, you should absolutely con-
tact with building designer to reinforce the floor slab or execute special
structure distributing the weight on a larger area.
Flooring in the room, where the stove is to be installed,
should be properly dimensioned, to maintain the load.
To ensure correct operation of fireplace insert you should ensure
suitable inflow of air required for combustion (it is appropriate to ensure
approx. 40 m /h) in accordance with the installation standards and
3
standards applicable in the given country. The volume of the surround-
ing environment should not be less than 30 m
that combustion of 1 kg of wood requires ~8 m
WARNING !!!
Lack of expansion joint may be a reason of equipment damage
what is connected with loss of the warranty rights.
If several inserts are to be used in one room the air de-
mand should be met for each insert.
It is forbidden to install fireplace inserts in G version in
so-called "hot" installation. Such an installation will
void the warranty.
Insert housing should ensure access of air necessary for ventila-
tion, air circulation in the housing. In the bottom part of the installation
(under the insert) it is appropriate to ensure air supply openings ensur-
ing air supply for combustion. To ensure correct discharge of hot air
from the hood you should install exhaust openings ended with ventila-
tion grilles. This opening should be made in a way ensuring that they
cannot be plugged. They should be ended with grilles.
Insulation inside the housing,
80 mm
20-30 mm
facade of
fireplace insert
ceiling
wall
80 mm
. You should assume
3
of air.
3
Fireplaces in G version are not intended for a so-called "hot" instal-
lation due to required cooling of the doors mechanism. Installation of
DEFRO HOME INTRA G fireplace insert in such system will void the
warranty. It is indicated to use bigger expansion joint what translates
into longer and trouble-free operation of doors mechanism.
The active area of the grille should be selected correspondingly to
the power of the insert. It is assumed that is should equal to 40 - 60
cm per 1 kW of the power of the insert. Recommended active surfaces:
2

fireplace insert power to 10 kW - grille cross-section min. 500
cm 2 ,

fireplace insert power to 15 kW - grille cross-section min. 700
cm ,
2

fireplace insert power over 15 kW - grille cross-section min.
800-1200 cm and more.
2
Air can be supplied from adjacent rooms, provided that they are
equipped with external air supply and they are not intended for a bed-
room and bathroom, and where fire hazard is not present, for example:
garages, woodsheds, inflammable materials storage. You should ab-
solutely observe recommendations of the applicable standards.
Temperature over the insert, inside the hood, is very high. There-
fore it is necessary to install a decompression relief plate inside the
hood, in distance ~40cm from the ceiling of the room. It prevents heat-
ing of the ceiling in the room, heat losses and forces installation of ex-
haust grilles below it emitting the heat from the relief chamber over the
insert. Relief grilles are installed alternately on both sides of the hous-
ing - below and over relief plate.

5.3. HOT AIR DISTRIBUTION SYSTEM

5.3.1. GRAVITY SYSTEM FOR HOT AIR DISTRIBUTION

In case of heating of small areas, e.g. room where the fireplace
insert is installed, and adjacent rooms, you should select gravity system
for air distribution, when the hot air will raise upwards to the chamber
in heating ducts by way of thermal lifting forces.
air girlle
of decomrpession
chamber
insulated
decompressio plate
convetion air
outlet grille
convetion
air inlet
Picture 28. Hot air distribution system.
Using of the gravity system you should use properly insulated and
short (not exceeding 3 m) distributing ducts. For this system it is not
recommended to distribute hot air to too many rooms. Also use of too
long pipes (over 3 m from the flue) increases resistance and decreases
air flow velocity what causes that gravity flow is not effective.

5.3.2. FORCED SYSTEM FOR HOT AIR DISTRIBUTION

Application of forced system for hot air distribution (DGP) requires
the installation of air supply device (turbine). It sucks hot air heated by
the fireplace insert and forces it to all branches of the system. In such
case you should use a pipe connecting flue with an air supply unit with
the biggest possible cross-section and the smallest possible length
hot air outlet
flue gas outlet
connection
housing
with insulation
air inlet
for combustion
from outside
15