Viessmann Vitomax 200-LW M64A, Инструкция по эксплуатации и обслуживанию

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■ Where water treatment is required,
treat even the first fill of the heating
systems prior to commissioning. This
also applies to any subsequent filling,
e.g. when adding top-up water, after a
repair or after system expansion.
■ Filters, dirt traps and other blow-down
or separating facilities in the heating
water circuit must be checked,
cleaned and activated more frequently
after commissioning or recommission-
ing, and later on as required, subject
to the water treatment applied (e.g.
water softening).
The build-up of limescale deposits on the
heating surfaces will be minimised if
these instructions are observed.
Any limescale deposits that have formed
because the requirements to VDI Direc-
tive 2035 have not been observed will in
most cases already have caused a
reduction in the service life of the instal-
led heating equipment. Removing the
limescale deposits is one option for
restoring operational viability. This
measure must be carried out by the
Viessmann Industrieservice or a special-
ist company. Inspect the heating system
for possible damage prior to returning it
into use. It is essential that the faulty
operating parameters are corrected to
prevent renewed formation of excessive
scale deposits.
Prevention of damage through corrosion on the water side
The corrosion resistance of ferrous
materials on the heating water side of
heating systems and boilers depends on
the absence of oxygen in the heating
water.
The oxygen introduced into the heating
system with the first fill and the top-up
water reacts with the system materials
without causing damage.
The characteristic blackening of the
water after some time in use indicates
that free oxygen is no longer present.
The technical rules and in particular VDI
Directive 2035-2 therefore recommend
that heating systems are designed and
operated so that a constant ingress of
oxygen into the heating water is preven-
ted. Opportunities for oxygen ingress during
operation:
■ Through open expansion vessels
overflowing
■ Through negative pressure in the sys-
tem
■ Through gas-permeable components
Sealed systems – e.g. systems with a
diaphragm expansion vessel – offer
good protection against the ingress of
airborne oxygen into the system if they
are correctly sized and operate at the
correct pressure.
At every part of the heating system, even
at the suction side of the pump and under
all operating conditions, the system
pressure should be above ambient
atmospheric pressure.
Water quality requirements
Water quality requirements
(cont.)
5727 529 GB
Service