Sime Murelle 25 BF, Installer'S Instructions

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3.6 SEPARATE DUCTS
(Optional alternative twin pipe system)
When installing the separate ducts, comply with the require-
ments of the current standards, as well as the following prac-
tical pointers:
– With direct intake from outside, when the pipe is longer
than 1 m, you are recommended to insulate the piping so
as to prevent formation of dew on the outside of the piping
during particularly cold periods of the year.
– With the outlet pipe outside the building or in cold indoor
environments, insulation is necessary to prevent burner
ignition failure. In such cases, provide for condensate
drainage.
– If a segment of the flue passes through a flammable wall,
this segment must be insulated with a glass wool pipe insu-
lator 30 mm thick, with a density of 50 kg/m
3 .
The maximum overall length of the intake and exhaust ducts
depends on the head losses of the single fittings installed
(excluding the adaptors) and must not be greater than 7.5
mm H
2
O (“80 C” model) and 11 mm H
2
O (“100 C” model).
For head losses in the fittings, refer to
Table 8.
3.6.1 Separate flue accessories
Part No 8089904 is supplied for this purpose.
The sectored diaphragm is to be used according to the max-
imum head loss allowed in both pipes, as given in fig. 14.
11
Example of allowable installation calculation ( “FORMAT 80
C” model) in that the sum of the head losses of the single
fittings is less than 7.5 mm H
2
O:
Intake Outlet
7 meter horizontal pipe ø 80 x 0.20 1.40 –
7 meter vertical pipe ø 80 x 0.30 – 2.10
n° 2 90° elbows ø 80 x 0.30 0.60 –
n° 2 90° elbows ø 80 x 0.40 – 0.80
N° 1 terminal ø 80 0.10 0.30
Total head loss 2.10 + 3.20
= 5.3 mm H
2
O
With this total head loss, remove the segments from n. 1
to n. 8 from diaphragm in the intake pipe.
TABLE 8
Accessories ø 80 Head loss (mm H
2
O)
“FORMAT 80 C” “FORMAT 100 C”
Inlet Outlet Roof outlet Inlet Outlet Roof outlet
90° elbow MF 0,30 0,40 – 0,30 0,50 –
45° elbow MF 0,20 0,30 – 0,20 0,40 –
Extension L. 1000 (horizontal) 0,20 0,30 – 0,20 0,40 –
Extension L. 1000 (vertical) 0,10 0,20 – 0,10 0,30 –
Outlet terminal – 0,30 – – 0,40 –
Intake terminal 0,10 – – 0,10 – –
Doubler fitting 0,50 1,50 – 0,50 1,80 –
Roof outlet terminal L.1240 – – 0,50 – – 0,60
Tee condensation outlet – 0,90 – – 1,10 –
1
2
3
4
6
165
110
165
K
ø 80
ø 80
100
92
Fig. 13
KEY
1
Sponge-rubber gasket ø 125/95
2 Fixing screw
3 Smoke outlet flange
4 Air intake diaphragm
6 Air/smoke manifold with intakes
80 C 100 C
K mm 180 205