12
JUDO MAFI
Operation
Magnetic separator
Magnetite sludge (Fe
3
O
4
) present in a
closed loop heating or cooling system can
result in malfunction of individual systems
components, massive loss of operating effi-
ciency and, worst case, systems failure.
With its three high efficiency magnets (
1
) the
magnetite filter ensures that magnetic
sludge (
2
) is trapped and then physically re-
moved from the system by regular rinsing
(see fig. 6).
Before rinsing, close the shut-off valve
downstream of the magnetite filter, then pull
the magnet holder on the front of the unit to-
wards you to allow the sludge collected
there to drop to the unit floor (see chapter
“Cleaning the magnetic separator”). A rinse
may then be carried out (see chapters “Rins-
ing” and “Rinse interval”). The magnetite fil-
ter operates in a constant flow rate and
causes only a small pressure loss.
High levels of oxygen concentration can al-
so be found in closed loop systems. Weak
points within the system (e.g. non diffusion
resistant plastic pipes or membranes) mean
that O
2
can enter the system on an ongoing
basis. In combination with water, this results
in surface corrosion successively removing
material. The rate of this corrosion progress
is mainly determined by the factors O
2
con-
tent and time. Systems containing sludge so
formed are not only more liable to malfunc-
tion, but also operate at much lower efficien-
cy levels. The water quality within such sys-
tems is often unstable and, especially where
movement is less volatile, at the upper limits
of requirements. A result of this may be cor-
rosion (pitting) and resulting leakage.
Sludge deposits greatly affect the rate of
heat transfer. Although the performance da-
ta is constantly dropping, the actual cause of
the problem is often not recognised until it is
too late.
Fig. 6:
Magnetic separator in operation
1
2
1 High performance magnets
2 Magnetic sludge
