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Subject to technical amendments without prior notice | 83070100bUK | ait-deutschland GmbH
9
Flushing, filling and venting
9.1 Heating water quality
NOTE
●
For detailed information, see also the
VDI Guidelines 2035 "Vermeidung von
Schäden in Warmwasserheizanlagen"
(preventing damage in hot water heating
systems).
●
Required pH value: 8.2-10;
For aluminium materials:
pH value: 8.2-8.5
► Only fill the system with demineralised heating
water or with VDI 2035 equivalent water (for low-
salt operation of the system).
Advantages of low-salt operation:
●
Minimal corrosion
●
No formation of mineral scale
●
Ideal for closed heating circuits
● Ideal pH value due to self-alkalisation after filling
the system
►
If the required water quality is not achieved, con-
sult a company that specialises in treatment of
heating water.
►
It is advisable to keep a system log for hot water
heating systems containing the relevant planning
& design data (VDI 2035).
Anti-freeze in the heating circuit
For air/water heat pumps installed outdoors, it is not
necessary to add a water-antifreeze mixture into the
heating circuit.
The heat pumps have safety devices which prevent
the water from freezing even when the heating is
switched off. The prerequisite is that the heat pump re
-
mains switched on and is not disconnected from the
power supply. If there is a risk of frost, the circulation
pumps are activated.
If the heating circuit is filled with anti-freeze, and de
-
pending on the concentration of the mixture, the fol-
lowing points must be observed:
●
The heating capacity of the heat pump is reduced
●
The COP value becomes worse
●
The output of circulation pumps used on site is re-
duced, and the specified free compression for in
-
tegrated circulation pumps decreases
●
You must ensure the materials in the components
used are compatible with the anti-freeze mixture
9.2
Flushing and filling the heating
and domestic hot water charging
circuit
The outlet pipe of the safety valve must be con-
nected.
►
Ensure that the set pressure of the safety valve is
not exceeded.
1. Vent the system at the highest point in each case.
2. Vent the heat pump on the hydraulic connection
set.
3. Open the vent valve
(①)
on the 3-way switching
valve.
1
4. Pull the U-clip
(②)
on the rear of the valve motor
(③)
upwards on the 3-way switching valve.
2
3
4
