Rational Combi Master, Training Manual

Page: 140 / 200

140
Common Information
Edition 10-2008a
Water info
Because of continuous examinations of systems for water treatment we would like to offer you a few
information on some different systems.
The given statements are only related to Rational units.
If you already have made experiences with systems for water treatment, we would be very thankful if
you could send us a short fax about your experiences.
1. Recommended systems for water treatment:
A)
With pure scale problems in the steam generator we recommend hydrogen-(H+)-Ionic ex-
changer. These type of lters will extend the intervals of descaling to
approx. 5 to 8-times of the normal descaling intervals. But even with this type of lters it is
still necessary to descale the steam generator.
B) With a high chloride – content above 150mg/l of water, it is possible, that the
interior cabinet starts to corrode. To remedy this problem it is necessary to install a reverse -
osmosis – lter.
C) With chlorine-contents above 0,2 mg/l of water an active carbon lter should be installed, to
avoid corrosive radicals when chlorine is heated up.
D) If the water is soiled with sand, iron particles or suspended matters a particle lter with
5-15 m is recommended.
2. Limited recommended systems for water treatment .
A) Phosphate dosing systems
For verifying the function of this system, it is necessary to mix the water with a very high
content of phosphate. Because of this the maximum allowed content of 5 mg phosphate per
litre of water will be exceeded. This means the water has no drinking water quality any more.
Therefore phosphate dosing systems can only be recommended for avoiding scale in the
quenching chamber as it is not necessary to have drinking water quality for the quenching
system.
B) Physical systems for water treatment:
On some sites this type of water treatment (is directly installed in the water supply of the
unit) showed satisfactory results. On other sites there was no positive effect visible with this
type of system. Because of these circumstances we can not make a nal assessment of this
system.
3. Not recommended systems for water treatment.
A) Sodium-Ionic exchanger:
With this lter system calcium is replaced by sodium. On chlorine contents of the water above
50mg/l, sodium reacts with chlorine to NaCl (=salt). This increase of salt in the water results
in a delay in boiling of the water. This delay in boiling can cause ”spitting” steam generators.
B) Silicate-dosing systems:
This kind of systems are problematic, as the adding of non conductive silicates, will in uence
the water level measurement.
Rational recommends Water treatment lters systems of BRITA company.