ENERGIE
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15.4
Water filter
The filter allows block any impurities present in the hydraulic circuits. Residue
left in the heater pipes will damage the heat exchangers and cause the heat
pumps to malfunction. It is recommended install the filter in the heater return
line, especially if no buffer storage is present. It is indispensable in order to
prevent serious damage to the heat exchanger.
Note 1:
The filter must contain a filtering mesh with holes that do not exceed
one millimeter.
Note 2;
The filter should be kept cleaned and inspected periodically to
maintain your condition, cleanliness and ensuring the proper functioning of
Heat pump
15.5
Pressure drops (water filter)
15.6
Heating water quality
The composition and quality of the water in the system has a direct effect on
the performance of the entire system and the lifetime of the heat pump.
For the initial charging and backfill of the system, usually normal tap water
with a pH value of 7-8 can be used as long as the water is not highly corrosive
(chloride content > 150 mg/l) or hard (>14°dH; degree of hardness IV). A
drinking water analysis can be requested from the local water supply
company.
If the specific system volume is greater than 25 liters/kW heating output (e.g.
through the installation of a hot water buffer storage), then the maximum
permissible calcium carbonate input from the charging and backfilling water
should be calculated in accordance with the VDI guideline 2035. In some
cases the charging water has to be softened.
Note:
The use of chemical anti-corrosion agents is not permitted.
Criteria
Max. value
Effects of non-compliance
PH - Wert
7-8
Danger of corrosion in boiler parts
and heating system
Degree of hardness
< 14dH
- Increased lime deposits
- Reduced lifetime of boiler
Chloride content
< 150mg/l
Corrosion of alloyed materials
0
2
4
6
8
10
12
14
16
18
20
22
0,6
1
1,5
2
2,5
3
3,5
3,75
P
re
ss
u
re
d
ro
p
s
[K
P
a]
Water flow [m³/h]