Direct Venting (Two-Pipe System); Direct Venting Options (Two-Pipe System); Exhaust Vent/Air Intake Requirements; Combustion Air Supply - Viessmann Vitodens 100-W WB1A-24 Installation Instructions Manual

Direct Venting (Two-pipe System)

Direct Venting Options (Two-pipe System)

Exhaust Vent/Air Intake Requirements

Combustion air supply

38
As opposed to coaxial venting
systems, the two-pipe venting system
draws combustion air through a
separate air intake pipe from the
outdoors. Flue gases are discharged to
the outdoors via the single-wall pipe of
the special venting system. The
two-pipe system is flexible in the
selection of materials offered by
different manufacturers and the
location of the vent/air intake
termination.
The Vitodens boiler is suitable for
sidewall, as well as vertical venting
using field supplied venting material.
The Vitodens 100-W and
Vitodens 200-W boilers are approved
for both, direct vent (sealed
combustion), as well as direct exhaust
(non-sealed combustion) operation in
both, horizontal and vertical
arrangements. For non-sealed
combustion vent systems (i.e. room-air
dependent), see appropriate section
under "Single-Pipe Venting" starting on
page 57 in this manual.
The boiler must be connected to a
direct vent system in which all air for
combustion is taken from the outside
atmosphere and all combustion
products are discharged safely to the
outdoors.
The boiler must be vented and supplied
with combustion air and exhaust vent
as described in this section. Ensure the
vent and combustion air supply comply
with these instructions.
Read the following exhaust vent/air
intake requirements carefully before
commencing with the installation.
Inspect all finished exhaust vent/air
intake piping to ensure:
H Vent/air intake pipe and fittings are of
approved material.
H Acceptable size, length and number
of elbows on combined vent/air
intake system.
H Installation is in accordance with
prevailing provisions of local codes.
H Installation complies with the
requirements of these instructions, as
well as the exhaust vent/air intake
supplier's instructions.
The exhaust vent and combustion air
intake system and terminations may be
installed in one of the following type
terminations (2-pipe system):
1. Horizontal air intake and exhaust
vent pipes
2. Vertical air intake and exhaust vent
pipes
3. Horizontal air intake pipe and vertical
exhaust vent pipe