Water Quality And Treatment; Water Connections - andrews CWH30/200 Installation, Operation And Maintenance Manual

WATER QUALITY AND TREATMENT

When installing Andrews Water Heaters we would
recommend the inclusion of water treatment and that
a water treatment specialist is consulted to ensure
the selection of the most appropriate system for each
particular installation.
In hard water areas in particular, scale formation can occur
in all hot water systems and various factors can infl uence
this such as water temperature, amount of water used and
the quality of the local water supply. B.S. 7953 states that
provision should be made for water treatment where the
local water hardness exceeds 200 parts per million (14
degree Clark).
For further information please refer to our Technical Data
Sheet - T/D027 Water Quality and Treatment Data Sheet
(available from www.andrewswaterheaters.co.uk).

WATER CONNECTIONS

An unvented system must be fi tted by an approved
installer.
Th e pressure reducing valve C1 will regulate the mains
water pressure at 3.5 bar (provided there is suffi cient
mains water pressure available). Th e maximum test
pressure should be 6 bar. Th e expansion vessel C3 supplied
is suitable for the stored volume of the heater and a
Fig 1
Expansion Vessel
comparative pipe work system.
Th e temperature and pressure relief valve(s) are factory
fi tted. FOR SYSTEMS WITH LARGER PIPE VOLUMES OR
ADDITIONAL STORAGE, EXPANSION VESSELS WITH MORE
CAPACITY ARE AVAILABLE.
We do not recommend the use of galvanised pipework
due to issues such as galvanic attack (British Standard
BS6644). Th e MAXXfl o has a number of copper and brass
components.
Th e cold water connection and the hot water connection
can be found on the top of the appliance, see Fig 1A and
1B. An extra connection is available for the benefi t of a
circulation line. Please note that a stop valve should be
fi tted in the circulation line.
Th e MAXXfl o range of storage water heaters are designed
to work from a mains fed unvented system. An unvented kit
to regulate the cold feed is supplied with each heater and
should be installed as Fig. 1, 1a and 1b plus drawings on
pages 5, 6 and 7.
Th e temperature and pressure relief valves are supplied
factory fi tted for external connection to a tundish
(supplied) and suitable drain. Th e MAXXfl o can also
operate on vented systems providing the minimum water
pressure is one bar.
MAXXfl o Water Heater
INSTALLATION • SECTION 3 11 11