Viessmann VITOCROSSAL 200 Service Instructions Manual page 87

Water quality requirements
Note
Observing the following requirements is
necessary to safeguard your warranty
rights.
Prevention of damage due to scaling
Prevent excessive scale build-up (cal-
cium carbonate) on the heating surfaces.
For heating systems with operating tem-
peratures up to 100 °C, guideline
VDI 2035-1 "Prevention of damage in
water heating installations - Scale for-
mation in domestic hot water supply
installations and water heating installa-
tions" applies [in Germany], with the fol-
lowing standard values (see also the full
explanations in the original guideline).
Total heating output
kW
> 50 to ≤ 200
> 200 to ≤ 600
> 600
The standard values assume the follow-
ing:
■ The total volume of fill and top-up
water will not exceed three times the
water content of the heating system
during its service life.
■ The specific system volume is less
than 20 l/kW heating output. In multi
boiler systems, apply the output of the
smallest boiler.
■ All measures to prevent corrosion on
the water side in accordance with
VDI 2035-2 have been implemented.
The warranty excludes damage due to
corrosion and scaling.
Total alkaline earths
3
mol/m
≤ 2.0
≤ 1.5
< 0.02
Soften the fill and top-up water in heating
systems operating under the following
conditions:
■ The total of alkaline earths in the fill
and top-up water exceeds the stand-
ard value.
■ Higher fill and top-up water volumes
are expected.
■ The specific system volume is greater
than 20 l/kW heating output. In multi
boiler systems, apply the output of the
smallest boiler.
Total hardness
°dH
≤ 11.2
≤ 8.4
< 0.11
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