Water Softening System - Electrolux EDW 503 Service Manual

Water softening system

Operation of the water softening system
When water is admitted, the inlet valve (1) opens and the
hard water flows down into the ion exchanger (5),
through which it flows and is softened before flowing
through the water inlet (6) and then being sprayed into
the Washing chamber.
!n the meantime, the container for the regeneration
water (2) is also filled with water.
lf the rubber plug (3) at the rear of the machine is in place
as shown in the ilustration, the machine can handle
water with a hardness of up to 20'dH. !f the rubber plug
is removed. The regeneration water volume will be
increased, and the machine can then handle water with
a hardness of up to 35°dH.
During the dishwashing programme, the ion exchanger
will gradually be filled with lime and, to be able to soften
the water during the next dishwashing cycle, the ion
exchanger must be restored to its original condition.
This is done by a process known as regeneration, which
takes place according to the actual programmer dia-
gram.
The solenoid valve (7) between the salt container and
the ion exchanger will then open, and regeneration
water will flow into the salt container (4).
A corresponding amount of water saturated with salt is
thus forced into the ion exchanger. The salt solution is
present in the ion exchanger during the last rinse, and
the small plastic balls will be recharged with sodium ions.
According to the actual programmer diagram, the inlet
valve will open and will allow about 2 litres of water to flow
through the ion exchanger to flush away the now dissolved
lime residues. The lime-rich water is then flushed
immediately out to drain, and the machine is reset and
ready for the next water fill.
The whole of this process is integrated into the
programme of a machine with water softening, and thus
takes place fully automatically.
It should also be noted that it is important to use only
coarse salt, since fine-grained salt would. form lumps.
Water which is rich in lime is said to be "hard".
Water hardness is measured in German degrees
of hardness (dH). Water up to 10dH is normally
regarded as soft, and above this value, it is
regarded as hard.
The phosphates in the detergent can handle the
hard-
ness in soft water. But if the water is hard,
precipitations will occur, i.e. lime will be deposited
on the dishes and in the dishwasher.
Spares Operation - R.Kurzke 11/06
- 8 -
599 528 133 EN