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7 Commissioning [specialist]
18
99640x5xx-mub-en – V01
2020/06
7.1
Filling the primary circuit
WARNING
Danger of scalding due to hot water!
The system is under pressure. By opening the vent valve, hot water with a
temperature of up to 90 °C may exit and cause personal injury.
Open the vent valve slowly and with sufficient distance.
If the storage tank is (partly) filled
1.
Slowly open the ball valve (N) by turning it to
position 0°.
2.
Fill the storage tank using the fill valves available on
site until an operating pressure of about 1.5 bars* is
reached. Use heating water compliant with the
standards VDI 2035 / ÖNorm H5195-1.
3.
Manipulate the vent valve (L) cautiously to let the air
escape.
5.
Close the vent valve (L).
6.
Close the ball valve (N) by turning it into
position 90°.
7.
Check the operating pressure of the storage tank
after the venting and increase the pressure if
necessary.
8.
Open the ball valves (A) and (N) completely by
turning them into position 0°.
Primary circuit
* 1.5 bars in the primary circuit = recommended minimum value
The pressure also depends on the individual system pressures and on the components of the heating
installation!