600mm Max.
300mm
Min.
Temperature & pressure
relief valve
Metal discharge pipe (D1) from
temperature & pressure relief valve.
to tundish.
Metal discharge pipe (D2) from tundish
with continuous fall. See Table 2 and worked
example.
Tundish
Fixed grating
Trapped gulley
Discharge below
fixed grating.
(see page 10 for
alternative points
of discharge).
15
The single common discharge pipe should be at least one pipe
size large than the largest individual discharge pipe to be
connected. If unvented hot water storage systems are installed
where discharges from safety devices may not be apparent i.e. in
dwellings occupied by the blind, infirm or disabled people,
consideration should be given to the installation of an
electronically operated device to warn when discharge takes
place.
Note: The discharge will consist of scalding water and steam.
Asphalt, roofing felt and non-metallic rainwater goods may be
damaged by such discharges.