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5.3
Checking activities before commissioning
Before the boiler is put into operation it is necessary to check:
a) Filling the heating system with water
Water for filling the boiler and heating system must be clear and colourless, without any suspended
substances, oil and chemically aggressive substances. Its hardness must comply with
Č
SN 07 7401 and
in case of dissatisfactory hardness the water must be trated. Even a multiply heating of water with an
exceeded harness does not prevent the salts from segregation on the exchanger walls. By precipitation of
1 mm calcacite at a given point the heat transfer from metal to water is reduced by 10 %.
The heating systems with an open expansion tank allow a direct contact between the heating water and
the atmosphere. During the heating season the expanding water in the reservoir absorbs the oxygen
which increases the corrosive effects and at the same time lot of water evaporates. Only the water treated
to the values according to
Č
SN 07 7401 can be used for refilling. The heating system must be thoroughly
flushed out in order to wash out all impurities.
During the heating season it is necessary to keep a constant water volume in the heating system. When
refilling the water in the heating system it is necessary to make sure that no air is sucked into the system.
The water from boiler and the heating system must never be discharged or be taken for use except the
emergency cases like the repairs, ect. The water discharge and new water filling operations increase the
danger of corrosion and the scale formation.
If it is necessary to refill water in the heating system, we only do it when the boiler has cooled
down so that the exchanger cannot be damaged.
Fig. no. 23
Connecting dimensions of boiler
b) Heating system tightness
c) Connection to the chimney – must be approved by a chimney-sweepers´ organization
d) Burner tightness
