Technical data

Vitorond 200, VD2A Technical Data
5354 787 - 01
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System Design Considerations (continued)
System Design
Anti-vibration measures
Anti-vibration supports can be field supplied as an
economical and effective solution to combat noise
generated.
When sizing such supports, take the entire operating
weight of the boiler system and, when using longitudinal
anti-vibration brackets, the condition of the supporting
surface into consideration.
Effective anti-vibration measures are particularly important
when installing boilers into an attic. Compensators may
be used to physically separate the combustion equipment
from the building.
These should be installed into the boiler flow, return
and safety pipe and as near as possible to the boiler.
Also insulate any braces or hanging arrangements,
if installed, against sound/ vibration transmission to the
building.
Seismic restrainer
Viessmann offers an engineered seismic restraining
kit for compliance with local seismic requirements
for buildings and structures. Please contact your local
Viessmann Sales Representative for more details.
Warranty
Our warranty does not cover damages resulting from
the following:
- Corrosion caused by flue gas condensation due
to low boiler water and/or return water temperatures.
- Operation with contaminated fill and supplementary
feed water.
Sound attenuation
Please consult a professional engineer who is specialized
in noise attenuation for advice.
The burner/boiler systems, circulation pumps and other
auxiliary equipment used in heating systems generate
noise. This noise is transferred from the boiler room via
floorboards, ceiling and walls to neighboring rooms and
via the flue gas system as well as the ventilation air and
exhaust air apertures into other rooms and into the open,
where they may cause a nuisance.
To avoid this from happening, additional protective
measures may be required which should be considered
at the design stage. Subsequent measures to reduce
noise nuisance frequently require extensive effort and
expenditure.
Airborne noise attenuation
Frequently, modern boilers are equipped with silencer
hoods or sound insulated ventilation air inlet housings.
Additional silencer hoods may be used where more
stringent anti-noise measures are required. These
measures may be implemented later with minimal effort.
Silencer hoods are offered (usually by the burner
manufacturer) for various levels of noise attenuation
and are generally designed and built in accordance with
specific system conditions (boiler type, fuel supply,
building characteristics).
For larger systems, it may be necessary to route the
ventilation air through a sound-insulated channel, in order
to avoid noise nuisance outside the building.
Flue gas silencers are generally only required where higher
noise protection measures are called for. Whether or not
a flue gas silencer is required can be difficult to predict,
because of the complexity of the creation and propagation
of flame noise, the interaction between the burner, boiler
and the flue gas system as well as the operating mode
(flue gas system operating with positive or negative
pressure).
It is advisable, therefore, to assess the noise emission
into the neighborhood and to consider the sound pressure
level measured at the flue gas system outlet. It should
be considered at the planning stage whether silencers
might become necessary later.
In planning for its possible use, it is important that
sufficient space for the flue gas silencer is available
behind the boiler.
Good engineering practice mandates that the exhaust
pressure drop of the silencer be included in the vent size
calculation.