Vaillant geoTHERM Installation Instructions Manual page 15

(unsuitable) appears in the "Stainless Steel" column or if
the property "à" appears three times, operation with an
intermediate circuit is not permitted.
When water from lakes and ponds is used, an intermediate
circuit must always be installed. The intermediate circuit
must be filled with brine fluid (30 % mixture).
Water components Concentration
Iron, dissolved
Fe **
Manganese, dissolved
Mn **
Aluminium, dissolved
Al
Hydrogen sulphide
H S
2
Sulphide
SO
3
Chlorine gas, free
Cl
2
Ammonia
NH
3
Carbonic acid,
free aggressive
CO
2
Oxygen
O
2
Sulphate
2-
[SO ]
4
Hydrogen carbonate
-
HCO
3
Ratio
- 2-
HCO /[SO ]
3 4
Chloride
-
Cl
Nitrate, dissolved
NO
3
Optical characteris-
tics ***
Water
overall hardness
pH value
Electrical conductivity
10 - 500 mS/cm
(at 20 °C)
4.2 Well water quality limit values
Installation instructions geoTHERM 0020051574_04
Copper Stainless
in mg/l steel
(1.4401)
¨
< 0.2
¯**
> 0.2
¨
< 0.1
¯**
> 0.1
¨
< 0.2
à
> 0.2
¨
< 0.05
¯
> 0.05
¨
< 1
¨
< 0.5
à/¯
0.5 - 5
> 5
¯
¨
< 2
à
2 - 20
> 20
¯
¨
< 5
à
5 - 20
> 20
¯
¨
< 2
à
> 2
¨
< 70
à/¯
70 - 300
> 300 ¯
à
< 70
¨
70 - 300
> 300 à
à/¯
<1.0
¨
>1.0
¨
< 300
à
> 300
¨
< 100
à
> 100
Limit value Clear, Clear,
colour- colour-
less less
¨
4.0 - 8.5 °dH
à
< 6.0
à
6.0 - 7.5
7.5 - 9.0
¨
> 9.0
à
<10 mS/cm à
¨
>500 mS/cm
¯
¨ = Resistance normally good
à = Danger of corrosion; if several criteria are rated with à: critical
¯ =unsuitable
**) To prevent the sedimentation of iron ochre, especially in the
absorbing well, a limit value of < 0.2 mg/litre for iron (Fe) and
< 0.1 mg/litre for manganese (Mn) must be observed.
***) Cloudiness or settleable substances must not be present in the
groundwater, irrespective of the statutory regulations.
Extremely fine dirt particles that lead to clouding of the water
also cannot be eliminated by filters. They may therefore accu-
¨
mulate in the evaporator and adversely affect the heat transfer
¨
performance.
¨
¨
¨
¨
¨
¨
¨
¨
¨
à/¯
¨
¨
¨
¨
¨
¨
¨
¨
¨
¨
¯
¨
¨
¨
¨
¨
¨
à
¨
¨
¨
à
à/¨
¨
¨
¨
¨
¨
Installation 4
15