Hydropath Operational
Guidelines
Scale Prevention
Hydropath prevents the formation of hard scale due to increases
of temperature and pressure change, under all normal operating
conditions. Users are advised to contact ECMI Technical Support if
they suspect that conditions are unusual.
Scale Removal
Old scale is normally broken down. The time taken depends on the
volume of water, the flow of water to remove the excess scale
crystals, the porosity of the old scale and variations in the
temperature and the pressure of the water. In most cases the process
is fairly rapid, and up to 95% or more of old scale is broken down
and treated within the first three months.
Hard scale may be slow to break down where there is low water volume
and little variation of temperature, flow, hardness and pressure. In
such cases Hydropath is best fitted from new or after chemical
cleaning.
If Hydropath is applied to a heavily-scaled system, where scale
may have formed on the inside of a narrow pipe or plate heat
exchanger there is a small risk of blockage due to dislodged pieces
of scale. The user is advised to have a system cleanse or to install
suitable coarse filters prior to fitting Hydropath.
The Hydropath signal is effective both up and down stream, and can
cause a large quantity of scale to be broken down. In most cases the
only effect may be that users see the crystals as they emerge from
open taps. This does not always happen and stops within a few
months. There will be no adverse effect in a closed recirculation
system unless there is significant evaporation or there has
previously been some significant leakage.
Corrosion
The application of Hydropath cannot itself cause corrosion or
leaks. Scale is a direct cause of corrosion and its removal may
reveal leaks. Rust coatings in mild steel pipe-work are altered,
resulting in a hard black surface deposit, magnetite, rather than
normal rust and further corrosion is prevented. This effect is due
to an interference with the electro-chemical reaction needed for
corrosion to take effect.
Maintenance
Hydropath uses solid state circuitry and does not require
maintenance. Its signal cannot create films which would reduce
performance. There is a red light which is powered directly by the
generated signal and is a positive indication of correct operation.
If the operation of the device is critical, users should monitor
this light as part of a planned maintenance procedure. On the
commercial units, the BMS port can be tied into the system to
trigger an alert.
Residual Effect
Once water has left the plumbing system or left the protection
zone, it can no longer be subjected to the Hydropath conditioning
field. 30 minutes may be taken as a conservative guide to the time
that the water retains its full scale prevention ability.
Soft Scale
In systems with no turbulence the crystals can settle. This can
occur in commercial kettles, coffee machine reservoirs, large
calorifiers and cooling tower pools. The resulting soft scale is
removed during maintenance or using filters.
Recirculation Systems with Evaporation
Where a recirculation system involves evaporation, e.g. cooling
towers or humidifiers, the suspended crystals must be removed using
filtration (<50 microns) or blow down to avoid concentration. On
initial application existing scale will be broken down leading to an
excess of precipitate which users must address. The easiest approach
is to increase blow down. A suitable filter with automatic back wash
will also control the problem and will reduce water costs. pH can be
controlled using sulphuric acid to reduce the rate of precipitation.
Plate Heat Exchangers
When using Hydropath to protect plate heat exchangers, existing
scale in the pipes upstream of the device will be broken down and
may come off in large particles. This will lead to excess
precipitate in the heat exchangers which can continue to cause scale
for the first few weeks. If the plate heat exchanger is heated using
steam, it is advised that the hot steam supply is connected to the
same side as the water return. The heat exchanger will give
increased performance through the avoidance of boiling.
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