IDRO PRINCE
3
12-16-23-23 H
2
O - IDRO PRINCE 30-30 H
2
O - AQUOS
3
16-23-23 H
2
O - IDRON 16-22 AIRTIGHT - MIRA 16-22 - TESIS 16-23 AIRTIGHT - HIDROFIRE 22.8
14
3.8
SIZING
The vacuum (draft) of a flue also depends on its height. Check vacuum with the values shown in the technical features. Minimum
flue height is 3.5 metres.
The flue internal cross-section can be circular (best case), square, or rectangular (the ratio between the inner sides must be ≤1.5)
with the sides coupled with a 20mm minimum radius. Minimum cross-section must be Ø100mm.
The sections/lengths of the chimneys must, in any case, be properly sized according to the general calculation method used in UNI
EN13384-1 or other methods that have proven efficient.
Below are some examples of flues available on the market:
VERY GOOD
GOOD
POOR
VERY POOR
AISI 316 steel chimney with
insulated twin walls with
ceramic fibre or equivalent
resistant to 400°C.
Refractory chimney with
insulated twin walls and
external sleeve in lightweight
concrete with honeycomb
materials, like clay.
Traditional clay square section
chimney with hollow insula-
ting inserts.
Avoid chimneys with rectan-
gular inner section in which
the ratio between the longer
side and the shorter side is
greater than 1.5 (for example,
20x40 or 15x30).
3.9
MAINTENANCE
Flues must always be clean, as build-ups of soot or unburnt oil reduce the cross-section, blocking draft, compromising proper stove
operation, and, in large amounts, can catch fire. Have the flue and chimney cap checked and cleaned by a qualified chimney sweep
at least once a year and, after the check/service, have them issue an undersigned report that the system is safe.
Failure to clean compromises system safety.
3.10 CHIMNEY CAP
A chimney cap is a crucial element for the heating appliance to work well: we recommend a wind resistant type (A) chimney cap,
see
Fig. 9 - Examples of chimney caps
The area of the openings for smoke extraction must be at least twice the cross-section of the flue/ducted system and shaped so
that, even in the event of wind, smoke is still extracted. It must prevent rain, snow, and any animals from getting in. The height
of the opening must be beyond the backflow area cause by the shape of the roof or any obstacles that may be nearby (see
,
,
,
).
