Heat Exchanger Operating Limits - WATERKOTTE F41449 Planification Et Installation

Heat exchanger operating limits

14 Heat exchanger operating limits
When using groundwater as a heat source / domestic water in drinking water installations, the limiting values listed
below (see table and diagram) must be observed according to heat exchangers. The soldered plate heat exchanger
consists of embossed stainless steel plates 1.4401 or AISI 316. You must therefore take the corrosion behaviour of
stainless steel and the solder material, copper or nickel, into account.
Water constituent + value
pH value
Saturation index SI
(∆pH value)
Overall hardness
Conductivity
Filterable materials
Chloride (Cl-)
Free chlorine
Hydrogen sulphide (H2S)
Ammonia (NH3 / NH4+)
Sulphate (SO42-)
Hydrogen carbonate (HCO3)
Hydrogen carbonate / sul-
phate
Sulphite (SO32-)
Nitrate (NO3-)
Nitrite (NO2-)
Iron, dissolved (Fe)
Manganese (Mn)
Free aggressive carbon diox-
ide (H2CO3)
The above values are guide values which can vary under certain conditions.
24.10.2018
Plate heat exchanger,
Unit
Copper-soldered (standard)
7 – 9 (allowing for SI index)
°dH
μS/cm
mg/l
mg/l see diagram below, no chloride permissible above 100 °C
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
mg/l
Figure 5: Permissible chloride content depending on temperature
18 / 20
Copyright  2018 by: WATERKOTTE GmbH Subject to changes.
-0.2 < 0 < +0.2
6 – 15
10 ... 500
< 30
< 0.5
< 0.05
< 2
< 100
< 300
> 1
< 1
< 100
< 0.1
< 0.2
< 0.1
< 20
Plate heat exchanger
Nickel-soldered (standard)
6 – 10
not determined
6 – 15
not determined
< 30
< 0,5
not determined
not determined
< 300
not determined
not determined
< 5
not determined
not determined
not determined
not determined
not determined