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We reserve the right to make changes without any prior notice.
Translation from original instructions
To avoid damage to the mechanical seals, do not start the circulation pump before completely filling the
system with water.
If a pump has to be replaced, after replacing it, make sure the valves are open and the pump is full of water
before enabling its operation.
6.1.1 Checking the pre-charge of the expansion vessel
The values of the pre-charge pressure and the maximum pressure at which it can operate are stated on the label present
on the expansion vessel.
The pre-charge pressure of the expansion vessel must be adjusted to the hydraulic pressure at the point of installation.
At the time of installing the unit, make sure the pre-charge value is equal to the hydrostatic pressure value at the point of
installation increased by a precautionary pressure value (at least 0.3 bar), to ensure there are no areas under vacuum in
the system.
where
- pVE: new pre-charge pressure of the expansion vessel [barg]
- Hmax: difference in level between the highest point of use and the installation level of the unit [m]
If the calibration value obtained from the calculation is lower than the pre-charge value stated on the label, keep the existing
pre-charge value.
The maximum value of the pre-charge pressure corresponds to the calibration pressure of the safety valve.
The checking of the pre-charge must be done for each installed vessel
6.1.2 Checking the volume of the expansion vessel
As the pre-charge pressure increases, the maximum volume of the system supported by the expansion vessel supplied as
standard, decreases.
where
- VI: volume of the system supported by the expansion vessel [l]
- VVE: volume of the expansion vessel [l]
- Ce: expansion coefficient of water
- pVE: pre-charge pressure of the expansion vessel [barg]
- pVS: calibration pressure of the safety valve [barg]
If the actual volume of the system is higher than this maximum value, an additional expansion vessel of adequate volume
must be installed.
After filling the hydraulic circuit, the pressure at the expansion vessel must be just a little higher than the pre-charge pres-
sure.
If there are points of use placed at levels lower than the level at which the unit is installed, check that the point of use is able
to withstand the maximum pressure that can be generated.
