Plumbing - Mira event Installation, Operation, Maintenance Manual

3. Plumbing

3.1. Do not use excessive force when making connections to the flexible
hoses or handset, finger tightness is sufficient.
3.2 Do not turn on the electrical supply until the plumbing connections have
been completed and the pump primed as the unit must not be operated
dry.
3.3 Do not solder supply pipework within 300mm of the appliance as
transmitted heat may melt the inlet manifold.
3.4 When installed, the top of the appliance must be at least 75mm lower
than the base of the cold water storage cistern to prevent the pump being
run dry.
3.5 Avoid layouts where the hose will be sharply kinked. This may reduce the
life of the hose.
3.6 The storage cistern should have a minimum storage capacity of 230 litres
to provide adequate showering time and to comply with BS6700 (1987).
Insufficient storage may result in the pump being run dry.
3.7 The action of a pump is to increase the flow rate. If the supply pipework
cannot handle the higher flow rate then:-
3.7.1 The expected flow rate may not be achieved.
3.7.2 Air may be drawn into the hot supply from the vent pipe, causing
spluttering and temperature fluctuations at the handset.
3.8 To prevent such operational difficulties the feed from the cylinder should
be as illustrated. Side entry cylinder bosses are not recommended
because:-
3.8.1 A drop in cylinder water level could expose a top entry immersion
element if fitted.
3.8.2 Air-in-water solution gathers at the edge of the cylinder and in the
centre, during the heating process before travelling up the vent.
3.9 A high level hot feed pipe run as illustrated will result in air locking and
should be avoided.
3.10 No form of flow control should be fitted to the outlet of the appliance.
3.11 Conveniently situated isolating valves should be fitted for servicing
purposes (Bye-law 68).
3.13 The use of white polyethylene plastic pipe suitable for hot water is
recommended to enhance the appearance of the finished installation,
when using surface mounted inlet supply pipework. Internal pipe supports
(not supplied) should be used with this type of pipe.
3.14 Use only the supplied Mira handset with this appliance.
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