Installation guide

Direct Venting (Two-pipe System)
42
Exhaust Vent/Air Intake Requirements (continued)
General requirements
The Vitodens 100-W and 200-W
boilers must be located in such a way
that the vent length is as short as
possible and that the vent can be
routed as directly (and with as few
bends) as possible.
The minimum equivalent vent length is
4 ft. / 1.2 m.
See tables NO TAG, 40. and 41. for
maximum and minimum vent lengths.
All products of combustion must be
safely vented to the outdoors.
The Vitodens boiler is not approved for
common-venting applications. Do not
common-vent with any other appliance.
The Vitodens boiler vents under
positive pressure and is a Category IV
boiler.
Viessmann recommends that the entire
vent system be checked by a licensed
professional heating contractor at least
once each year following initial
installation.
The stainless steel special venting
system is completely sealed when fully
assembled. Locking bands are used to
reinforce the joints between pipe and
fittings.
Do not install vent pipe in a way that
flue gases flow downwards. The
direction of flue gas flow must be
vertically upwards or horizontal with an
upward slope.
Ensure there is no flue gas leakage into
the area in which the boiler is installed.
Check joints for leaks with the gas
supply turned off and the fan running.
Use a soapy solution to check for vent
leaks.
Condensate must drain from the flue
pipe to the boiler. Ensure a suitable
gradient of at least 3º (approx. 2” per
3.3ft./50mmper1m).
No condensate trap is required in the
vent pipe system.
5368 815 v2.0 b
Failure to ensure that all flue gases
have been safely vented to the
outdoors can cause property damage,
severe personal injury, or loss of life.
Flue gases may contain deadly carbon
monoxide.
WARNING
Different manufacturers offer a
number of different joint systems and
adhesives. Do not mix pipes, fittings
and/or joining methods from different
manufacturers. Failure to comply
could result in leakage, potentially
causing personal injury or death.
WARNING