Page 334 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

The City & Guilds Textbook: Plumbing Book 1

● Electronic (electromagnetic): these cause dissolved hardness salts and
minerals to cluster together rather than form on surfaces.
● Electrochemical: typically German or Austrian made, these conditioners
contain a cartridge filled with ceramic beads that cause the magnesium and
calcium crystals to precipitate. The conditioner units are usually quite large,
requiring an electrical supply.

p Figure 5.114 Electromagnetic The benefits of installing a water conditioner include:
water conditioner
● reduction in the scale formation in pipes
● reduction of limescale on taps
● easier cleaning of showerheads and places where limescale may form.

Water softeners
A water softener is an appliance that is fitted directly to the water supply to
a domestic dwelling or a commercial building, specifically designed to remove
the water hardness. They are usually installed as close to water main entry
into the building as possible. Most modern softeners are very compact and can
easily be fitted under a kitchen sink.

Water softeners use a process called ion exchange. The
softener contains a column that is filled with special
Rising main
Water softener resin beads. These remove the dissolved calcium and
magnesium salts by replacing them with sodium as
the water passes through them. Once a day, the unit
automatically washes the beads with brine (salt water)
to remove calcium and magnesium ions, taking the
solution to drain. Every month, the unit has to be refilled
with salt in the form of granules, tablets or blocks.
Stop valve
Use of a water softener generally reduces the hardness
of the water from 350 mg/l (milligrams per litre) to less
than 10 mg/l.
When installing a water softener, there must be at least
p Figure 5.115 Fitting a water softener one unsoftened cold water outlet in the dwelling.

Drinking water filters
Drinking water filters alter the water composition to improve its taste, odour and
appearance for drinking and cooking purposes. There are two common types:

1 jug filters – filled from a tap and stored in a fridge
2 plumbed-in filters – usually sited underneath the kitchen sink with a separate
drinking water tap installed at the kitchen sink.

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