Planning
3066501_201910
WOLF GmbH | 15
4.3.2
Heating water
Limits
Limits
)
Measures
Possible consequences of
failing to follow instructions
Complied with
Use potable water as fill and top-up water.
-
Not complied with
Flush system with potable water.
High level of oxygen ingress
This water must be desalinated
using a dirt filter upstream from the ion
exchanger.
Warranty voided for water-side
system components.
Table 4.2 Treatment of heating water in accordance with VDI 2035
Heating water additives
NOTE
Heating water additives!
Damage to heating water heat exchanger.
► Do not use antifreeze or inhibitors.
NOTE
Corrosion of aluminium components due to pH levels being too high or too low!
Damage to heating water heat exchanger
► The pH value of the heating water must be between 6.5 and 9.0.
► In mixed installations, a pH value of 8.2 to 9.0 must be maintained in accordance with VDI 2035.
Electrical conductivity and water hardness
The limits for conductivity and water hardness are dependent on the specific system volume V
A
(V
A
= system volume / max. rated heating output).
According to VDI 2035, in systems with multiple boilers, use the maximum rated heating output of the
smallest heat generator.
Heating water quality requirement relating to the entire heating system:
Total heating output
V
A
≤ 20 L/kW
Total hardness
1
/ total alkaline earths
Conductivity
2
at 25°C
[kW]
[°dH]
[mol/m³]
Cond. [µS/cm]
≤ 50
≤ 16.8
≤ 3.0
< 800
50-200
≤ 11.2
≤ 2
< 100
Total heating output
V
A
> 20 L/kW and < 50 L/kW
Total hardness
1
/ total alkaline earths
Conductivity
2
at 25°C
[kW]
[°dH]
[mol/m³]
Cond. [µS/cm]
≤ 50
≤ 11.2
≤ 2
< 800
50-200
≤ 8.4
≤ 1.5
< 100
Total heating output
V
A
≥ 50 L/kW
Total hardness
1
/ total alkaline earths
Conductivity
2
at 25°C
[kW]
[°dH]
[mol/m³]
Cond. [µS/cm]
≤ 50
≤ 0.11
3
≤ 0.02
< 800
50-200
≤ 0.11
3
≤ 0.02
< 100
1
Total hardness conversion: 1 mol/m³ = 5.6 °dH = 10 °fH
2
< 800 µS/cm: high salinity / < 100 µS/cm: low salinity
3
< 0.11 °dH recommended standard, permissible up to limit of < 1 °dH
Table 4.3 Electrical conductivity and water hardness
