Water Systems And Pipework; Hydraulic System; Water Quality - Bosch CS 3000 AWP Installations- Und Bedienungsanleitung

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Water systems and pipework

5.1

Hydraulic system

The pipes must be designed and manufactured to limit pressure drops as
much as possible (i.e. optimise performance of the system).
Keep the following parameters to a minimum:
• Overall length
• Number of bends
• Changes of direction
5.2

Water quality

The water quality should be checked by qualified personnel.
Water with inadequate characteristics can cause:
• Increasing of pressure drop;
• Decreasing of energy efficiency;
• Increasing of symptoms of corrosion.
Water features must be:
• Within the limits indicated by the graphic;
• Comply with VDI 2035 requirements.
Provide a water treatment system, if values fall outside the limits.
NOTICE
The warranty does not cover damages caused by limestone
formations, deposits and impurities from the water supply and/or
from failure to clean the systems.
The following graphic can be used to decide whether a filling water
treatment is necessary. In the case of ambivalent systems, the highest
requirements of the heat generators used in the overall system apply.
3
V [m ]
2,60
2,40
2,20
2,00
1,80
1,60
1,40
1,20
1,00
0,80
0,60
0,40
0,20
0,00
0 5
Fig. 67 Requirements for filling and make-up water volume for heat
pumps <= 100 kW
[1] A - Above the curve, use fully demineralised filling water with an
electrical conductivity of <=10 microsiemens / cm
[2] B - Below the curve use untreated tap-water.
Fill in compliance with drinking water regulations
[3] H - Water hardness
w
[4] V - Total water volume: filling and make-up water volume of the
heating system during the service life of the heat pump
CS3000 AWP – 6721852570 (2022/11)
A
B
10 15
H [ºdH]
w
0010045166-001
CAUTION
With fully demineralised water, it is important to ensure that the
permissible pH value of 7.5 - 9 (permissible value for copper)
is complied with.
Failure to comply with this value can result in the heat pump being
destroyed.
▶ In the case of bivalent systems, check whether other heat generators
have different requirements.
Cleaning
Before connecting the water to the unit, clean the system thoroughly
with specific and effective products to remove residues or impurities
that may affect functioning.
Existing systems must be free from sludge and contaminants and
protected against build-ups.
New systems
In case of new installation, make sure to wash it entirely before
commissioning the central installation (certifies that the circulator is
uninstalled). This removes residues of the installation process (welding,
waste, joint products, etc.).
The system must then be filled with clean high-quality tap water.
Existing systems
If a new unit is installed on an existing system, the system must be rinsed
to avoid the presence of particles, sludge and waste. The system must be
drained before installing the new unit.
Dirt can be removed only with a suitable water flow.
Each section must then be washed separately.
Particular attention must also be paid to "blind spots" where a lot of dirt
can accumulate due to the reduced water flow.
The system must then be filled with clean high-quality tap water. If, after
rinsing, the quality of the water is still unsuitable, a few measures must
be taken to avoid problems.
An option to remove pollutants is to install a filter.
Risk of freeze
If the unit or the relative water connections can be subject to
temperatures close to 0ºC:
• Mix water with ethylene glycol, or;
• Safeguard the pipes with heating cables placed under the insulation,
or;
• Empty the system completely in case of long non-use.
Be aware that the unit must always be protected from freeze.
Otherwise, irreversible damage may occur.
Water systems and pipework
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