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6. ALTERNATIVE DISCHARGE AND SECONDARY RETURN
6.1 Alternative discharge
Downward discharges at low level, i.e. up to 100
mm above external surfaces such as car parks,
hard standings, grassed areas etc, are accept-
able providing that where children may play or
otherwise come into contact with discharges,
a wire cage or similar guard is positioned to
prevent contact, whilst maintaining visibility.
Discharge at high level, i.e. into a metal hop-
per and metal down pipe with the end of the
discharge pipe clearly visible (tundish visible or
not) or onto a roof capable of withstanding high
temperature discharges of water and 3 m from
any plastics guttering system that would collect
such discharges (tundish visible). Where a single
common discharge pipe serves more than one
system, it should be at least one pipe size larger
than the largest individual discharge pipe (D2)
to be connected. For further information contact
your Building Control Office or The British Board
of Agrément.
6.2 Secondary return
1. Secondary return fitting
2. Non return valve
3. Circulation pump
4. Secondary return line
5. Hot water draw-off to outlets
!
WARNING
The tundish shall be installed away from any
electrical devices.
