2.4
FLUES/CHIMNEYS
ENG
The flue or chimney used to release the pro-
FR
ducts of combustion into the atmosphere
must comply with current standards and
regulations.
Horizontal vent lengths must be supported
every I meter (39 in) or less to prevent sag-
ging.
The boiler can be exhausted using separate
pipe or forced draft. Follow the appropriate
instructions below for your particular venting
configuration.
2.4. 1
Installation separate
pipes (fig. 5)
The vent pipe must be certified ø 3" (76 mm)
category IV venting; for this type of flues it is
necessar y t o demand kit optional code
8089925 for tubes 3" in steel, and the kit
code 8089926 for tubes 3" in PVC or CPVC
TYPICAL PIPING
10
(standards with units). When installing the
pipes, follow closely the requirements of the
current standards and regulations, as well as
the following practical pointers:
1. With direct intake from outside, when the
pipe is longer than 1 m (3.28 ft -40 in),
you are recommended to insulate the
piping so as to prevent formation of dew
on the outside of the piping during particu-
larly hard periods of the year.
2
With the outlet pipe outside the building
or in cold indoor environments, insulation
is necessary to prevent burner failure
during trial for ignition. In such cases, pro-
vide for a condensatecollector system on
the piping.
3 If a segment of the flue passes through a
flammable wall, this segment must be
insulated with a glass wool pipe insulator 3
mm (1 in) thick, with a density of 50
kg/m3 (3lb/f t3) or follow vent manufac-
turers instructions for clearances to com-
bustibles.
4. The distance between the intake air and
the vent pipe must be within 300 mm (1 ft
- 12 in).
5. Slope the venting towards the wall hung
boiler, for long runs or installation where
condensation in vent may cause flame fai-
lure during trial for ignition provide a con-
densation collection on the piping, close to
the wall hung boiler.
The maximum overall length of the intake
and exhaust ducts depends on the head
osses of the single fittings installed and
must not be greater than 5 mm H
"W.C.).
For head losses in the fittings, refer to Table 2
- 2/a - 2/b.
O (0.20
2