INSTALLER
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These are contact between system water and air and the continuous addition of fresh water to the circuit.
To eliminate contact between system water and the air (thus avoiding oxygenation of the system water), we need to:
- ensure that the expansion vessel is a closed vessel, and of the correct size and pre-charge pressure (the pressure to
be checked periodically);
- ensure that the system is always kept at a pressure higher than atmospheric pressure at all points (including the pump
suction side) and under all operating conditions (precisely because the seals, gaskets and joins in a water circuit are
designed to resist pressure from within, but not to resist a vacuum within);
- ensure that no part of the system is made from materials that are permeable to gases (e.g. plastic pipes with no oxygen
barrier destined for under-floor heating systems).
b
Finally, never forget that boiler failures caused by encrustation and corrosion are not covered under the
terms of the warranty.
