53
Geberit Drainage Systems
Alternative stack ventilation system
6.2
Geberit air admittance valve
Function
The air admittance valve is closed in normal conditions.
The flow of waste water generates a negative pressure in
the pipe system which causes the valve to open, allowing
atmospheric air to flow in. The valve is closed immediately
and forms a seal after the pressure has equalised.
The Geberit air admittance valve GRB90 consists of:
1 Housing
2 Sleeve
1
2
Product standards
BS EN 12380 2003-03 Ventilation valves for drainage
systems - requirements, test
methods and evaluation of
conformity.
DIN 1986-100 2002-03 Drainage systems on private
ground - Part 100: additional
specifications to BS EN 752
and BS EN 12056.
BS EN 12056-1
Gravity drainage system
inside buildings - Part 1:
general and performance
requirements.
BS EN 12056-2
Gravity drainage system
inside buildings - Part 2:
sanitary pipework, layout and
calculation.
In conjunction with main ventilation, the valve can be used:
• As a replacement for the second main ventilation
system or recirculating air ventilation.
• As a replacement for indirect secondary
ventilation systems.
• For individual ventilation systems used in existing
drainage objects with drainage malfunctions.
6.2.1
Geberit air admittance
valve - GRB90
The housing colour and the colour of the sleeve are black
(white print).
The air admittance valves GRB90 can be connected to
the pipes, Geberit HDPE and Geberit Silent-db20 of the
dimensions ø 75 – ø 110mm.
The air admittance valves have different sleeves for
the different types of pipe (Geberit HDPE or Geberit
Silent-db20). The housing is the same for all air
admittance valves.
310.006.00.1
310.007.00.1
HDPE
Silent-db20
90mm air admittance valves can be connected to all pipe
types and dimensions Ø 75 to Ø 110mm from Geberit.
Maximum air capacity 35 l/s at –250 Pa.
Permitted temperature range -20°C to +60°C.
BS EN 12380 Designation A1
