6.10 Filling the heating circuit
Before filling the heating system, flush it thoroughly.
Important
The use of glycol to fill the heating circuit is formally prohibited.
The use of glycol in the heating circuit invalidates the warranty.
1. Fill the installation until a pressure of 0.15 to 0.2 MPa (1.5 to 2 bar) is
achieved.
2. Check for any water leaks.
3. Completely vent the indoor unit and the installation for optimum
running.
6.10.1 Flushing new installations and installations less than 6
months old
Before filling the heating installation, it is essential to remove any debris
(copper, caulking, soldering flux) from the installation.
1. Clean the installation with a powerful universal cleaner.
2. Flush the installation with at least 3 times the volume of water
contained in the central heating system (until the water runs clear and
shows no impurities).
6.10.2 Flushing an existing installation
Before filling the heating installation, it is essential to remove any sludge
deposits which have accumulated in the heating circuit over the years.
1. Remove any sludge from the installation.
2. Flush the installation with at least 3 times the volume of water
contained in the central heating system (until the water runs clear and
shows no impurities).
6.11 Filling the installation
6.11.1 Treatment of the heating water
In many cases, the heat pump and the heating system can be filled with
mains water, without treating the water.
Caution
Do not add any chemical products to the heating water without
first consulting a water treatment specialist. For example:
antifreeze, water softeners, products to increase or reduce the pH
value, chemical additives and/or inhibitors. These may cause
faults in the heat pump and damage the heat exchanger.
The water in the installation must comply with following characteristics:
Tab.43 Heating water specifications
Specifications
Unit
Total system output
≤ 70 kW
Hydrogen potential (pH)
7.5 - 9
Conductivity at 25°C
μS/cm
10 to 500
Chlorides
mg/litre
≤ 50
Other components
mg/litre
< 1
Total water hardness
°f
7 - 15
°dH
4 - 8.5
mmol/l
0.7 - 1.5
If water treatment proves necessary, Baxi recommends the following
manufacturers:
6 Installation
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