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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 pro-viding that where children may play or
otherwise come into con-tact with discharges,
a wire cage or similar guard is positioned to
prevent contact, whilst maintain-ing visibility.
Discharge at high level, i.e. into a metal hopper
and metal down pipe with the end of the dis-
charge pipe clearly visible (tundish visible or not)
or onto a roof capable of withstanding high tem-
perature discharges of water and 3 m from any
plastics guttering system that would collect such
discharges (tundish visible). Where a single pipe
serves a number of discharges, such as in blocks
of flats, the number served should be limited to
not more than 6 systems so that any installation
discharging can be traced reasonably easily. The
single common discharge pipe should be at least
one pipe size larger than the largest individual dis-
charge pipe to be connected. For further informa-
tion 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
