General Instructions - Kessel Staufix SWA Installation And Operating Manual

General instructions for installation of backwater valves
According to DIN EN 12056 it is not allowed to connect all drainage fix-
tures from a building (including those located above the backwater level
– ground level) through a backwater valve. The reason being that when
the backwater flap is in the closed position due to backwater / flooding
Correct installation of a backwater valve
Backwater valve
DIN EN 12056 specifically states that only drainage fixtures below the
backwater level may be connected to a backwater valve. All drainage
fixtures above the backwater level should be drained through a sepa-
rate pipe directly into the sewer (not through the backwater valve). This
means that the home / building must be equipped with separate drai-
2. Installation
no wastewater will be able to flow through the backwater valve meaning
that the building's own wastewater will flood out of the lowest drainage
fixture connected (normally in the basement) to the backwater valve.
Incorrect installation of a backwater valve
Right:
Backwater
level
Sewer
nage pipes. A building's wastewater from above the backwater level
(above ground level) can drain freely into the sewer at all times. Du-
ring backwater the higher head / pressure of wastewater above the
backwater level will force its way into the surcharged sewer and will not
flood the basement / lower levels. Rainwater drainage pipes must not
24
Backwater valve
Wrong
Backwater
level
Sewer